Fisher 785C Piston Actuators - Emerson Electric · 2020. 8. 20. · 3 Standard temperature -20 to 100 C (-4 to 212 F) and -40 to 100 C (-40 to 212 F) are PED 2014/68/EU and 2006/42/EC

www.Fisher.com

Fisher™ 785C Piston Actuators

ContentsIntroduction 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Scope of Manual 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . .Description 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Specifications 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Educational Services 3. . . . . . . . . . . . . . . . . . . . . . . . .

Principle of Operation 3. . . . . . . . . . . . . . . . . . . . . . . . .Installation 28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Actuator Earth Grounding 30. . . . . . . . . . . . . . . . . . . .Three‐Way Valve Applications Note 30. . . . . . . . . . . .

Actuator Mounting 41. . . . . . . . . . . . . . . . . . . . . . . . . . .Manual Override 30. . . . . . . . . . . . . . . . . . . . . . . . . . . .Handwheel Operation 30. . . . . . . . . . . . . . . . . . . . . . .

Maintenance 42. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Actuator Removal 43. . . . . . . . . . . . . . . . . . . . . . . . . .Disassembling the Pneumatic Cylinder 43. . . . . . . . .Assembling the Pneumatic Cylinder 36. . . . . . . . . . .Lubrication 38. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Disassembling the Handpump Hydraulic Cylinder 38Handpump Hydraulic Cylinder Seals Replacement 39Handpump Hydraulic Cylinder Reassembly 39. . . . .Other Maintenance Specifications 39. . . . . . . . . . . . .

Parts Ordering 56. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Parts Kits 56. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Parts List 59. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 1. Fisher 785C Springless Piston Actuator

Introduction

Scope of ManualThis instruction manual includes installation, maintenance, and parts information for the Fisher 785C piston actuator.Refer to separate instruction manuals for information regarding other equipment and accessories used with theseactuators.

Do not install, operate, or maintain 785C actuators without being fully trained and qualified in valve,actuator, and accessory installation, operation, and maintenance. To avoid personal injury or propertydamage, it is important to carefully read, understand, and follow all the contents of this manual,including all safety cautions and warnings. If you have any questions about these instructions, contactyour Emerson sales office before proceeding.

Instruction ManualD104483X012

785C ActuatorAugust 2020

https://www.emerson.com/en-us/contact-us



2

Table 1. Specifications

Operating Pressure(1)

Minimum: 2.7 barg (40 psig)Maximum Allowable: 10.3 barg (150 psig)

Consult your Emerson sales office for supplypressures under 2.7 barg (40 psig)

Travel(2)

25 mm (1 inch) through 610 mm (24 inch)See table 2 and 4

Thrust Capabilities

See table 3, 6, and 7

Stroking Speeds

Varies with actuator size, spring, travel, and supplypressure. If stroking speed is critical, consult yourEmerson sales office.

Piston Diameter and Area(2)

Available diameters range from 280 to 685 mm (11 to 27 inches).

See table 2 and 4

For additional sizes, contact your Emerson salesoffice.

Operative Temperature Limits(3)

Standard: -20 to 100�C (-4 to 212�F)

Low Temperature Options:

-40 to 100�C (-40 to 212�F) or-60 to 100�C (-76 to 212�F)

High Temperature Option:

-20 to 200�C (-4 to 392�F)

Yoke Boss and Valve Stem Diameter

� 127 mm (5 inch) yoke boss with 25.4 mm (1 inch) stem� 127 mm (5H inch) yoke boss with 32 mm (1-1/4 inch) stem� 178 mm (7 inch) yoke boss with 51 mm (2 inch) stem

Pressure Connections

Standard: 3/4 NPTOptional: 1 and 1-1/4 NPT

See table 8

Instrument Mounting

Mounting kits are available for use with FIELDVUE™

DVC6200 Series digital valve controllers

Construction Materials(4)

Part Material

Cylinder Carbon Steel

Nameplate and Travel Scale Stainless Steel

Piston Carbon Steel

Piston Rod Stainless Steel

Stem Connector Carbon Steel or Stainless Steel

Tie Rod Carbon Steel or Stainless Steel

Upper/Lower Heads Carbon Steel

Yoke Carbon Steel

Weights

See table 20, 21, 22, 23, 24, 25, 26, and 27

Lifting Point Load Ratings

See table 28 and figure 8 and 9

Options

� Top mounted handwheel� Side mounted handpump� Pneumatic fail mode via Fisher 377 trip valve� Volume boosters

Dimensions

See figure 2 and 5; tables 9, 10, 13, 13, 16, 15, and 19

Optional Certifications(5)

� Pressure Equipment Directive (PED) 2014/68/EUand Machinery Directive 2006/42/EC� ATEX Group II Category 2 Gas and Dust� Customs Union Technical Regulations (CUTR)010/2011 and 012/2011� Safety Instrumented System, SIL 3 Capable

1. The pressure/temperature limits in this bulletin and any other applicable standard or code should not be exceeded.2. Consult your Emerson sales office for longer travels or larger cylinder diameters. The Fisher 585C family of actuators can be used for smaller travels or cylinder diameters.3 Standard temperature -20 to 100�C (-4 to 212�F) and -40 to 100�C (-40 to 212�F) are PED 2014/68/EU and 2006/42/EC compliant. The low ambient temperature option, -60 to 100�C (-76 to 212�F)is not PED compliant. The high temperature option, if used in conjunction with ATEX, is limited to 135�C (275�F).4. Full stainless steel constructions are available upon request.5. Refer to the product nameplates to determine which certifications each actuator construction possesses




3

DescriptionThe 785C product lines encompass medium to large spring-return single-acting and double-acting piston actuatorsthat provide accurate, high thrust output for short to long travel applications. These actuators are designed for usewith a variety of medium to large Fisher sliding-stem control valves.

The single-acting actuators feature an internal bias spring that forces the actuator piston rod to extend or retract upona loss of supply pressure, thereby ensuring a fail-closed or fail-open mode of operation. This effectively eliminates theneed for a trip valve and volume tank in most constructions.

SpecificationsSpecifications for the 785C line of piston actuators are shown in tables 1 to 7. Refer to the nameplate affixed to theactuator yoke for specifications specific to individual constructions.

Educational ServicesFor information on available courses for Fisher 785C Series piston actuators, as well as a variety of other products,contact:

Emerson Automation SolutionsEducational Services - RegistrationPhone: 1-641-754-3771 or 1-800-338-8158E-mail: [email protected]/fishervalvetraining

Principle of Operation785C piston actuators utilize a pneumatically controlled piston that moves inside of a cylinder to generate thrust. Aseal contained on the circumference of the piston provides a seal between the top and bottom of the cylinder,preventing supply pressure leakage.

785C single-acting and double-acting spring-return piston actuators utilize a spring below the piston (outside thepressurized chamber) that will drive the piston rod upon a loss of supply pressure. This fail action will result in forcingan attached control valve to either fail-open or fail-closed.

From an equilibrium state, the actuator operates by reacting to a force unbalance that is created by increasing supplypressure on one side of the piston for single-acting and double-acting and decreasing it on the other side ofdouble-acting. This moves the piston up or down, and results in a repositioning of the attached control valve. Travelcan be adjusted using travel limits within a valve positioner, which limit the travel range of the actuator. The optionalmanual override does not have the ability to act as a hard travel stop.

An optional manual override (top mounted handwheel or side mounted handpump) is capable of extending orretracting the actuator manually and can be engaged at any position from full open to full close. The top-mountedhandwheel utilizes an engagement lever that couples the handwheel and piston rod. The handpump has a hydrauliccylinder attached to the piston rod. This enables the handpump to operate the actuator manually, unless thehandpump is set to bypass position.



4

Table 2. 785C Double-Acting Springless Standard Constructions(1)

ACTUATORSIZE

PISTON AREAVALVE STEM

CONNECTOR SIZEYOKE BOSSDIAMETER

AVAILABLE TRAVELWithout ManualOverride

With ManualOverride(2)

cm2 Inch2 cm2 Inch2 mm Inch mm Inch mm Inch

280 616 95 616 9525 1 127 5

25 - 610 1 - 24

32 1 1/4 127 5H

335 881 137 881 13725 1 127 5

32 1 1/4 127 5H

385 1164 180 1164 18025 1 127 5

32 1 1/4 127 5H

435 1486 230 1474 228

25 1 127 5

32 1 1/4 127 5H

51 2 178 7

485 1847 286 1828 283

25 1 127 5

32 1 1/4 127 5H

51 2 178 7

535 2248 348 2228 345

25 1 127 5

32 1 1/4 127 5H

51 2 178 7

585 2688 417 2660 41232 1 1/4 127 5H

51 2 178 7

635 3167 491 3139 48732 1 1/4 127 5H

51 2 178 7

685 3685 571 3657 56732 1 1/4 127 5H

51 2 178 7

1. Consult your Emerson sales office for additional sizes.2. Actuator size 280-385 are available with a top mounted handwheel. Size 435-685 are available with a manual handpump.

Table 3. 785C Double-Acting Springless Available Thrust

ACTUATOR SIZE

MAXIMUM ALLOWABLE CYLINDERPRESSURE

MAXIMUM ALLOWABLE THRUST

Without Manual Override With Manual Override(1)

barg psig N lb N lb

280

10.3 150

63682 14316 32635 7337

335 91157 20493 46715 10502

385 120399 27067 61700 13871

435 153702 34554 78726 17698

485 191066 42953 132291 29740

535 232492 52266 132291 29740

585 277979 62492 172788 38844

635 327527 73631 172788 38844

685 381137 85683 238555 53629

1. Actuator size 280-385 are available with a top mounted handwheel. Size 435-685 are available with a manual handpump.




5

Table 4. 785C Single-Acting Spring Return Standard Constructions(1)

ACTUATORSIZE

PISTON AREA VALVE STEMCONNECTOR

SIZE

YOKE BOSSDIAMETER

AVAILABLE TRAVELWithout Manual Override With Manual Override(2)

Rod Extends Rod Retracts Rod Extends Rod Retracts

cm2 Inch2 cm2 Inch2 cm2 Inch2 cm2 Inch2 mm Inch mm Inch mm Inch

335 881 137 869 135 881 137 869 13525 1 127 5

25.4 - 203 1 - 8

32 1 1/4 127 5H

385 1164 180 1152 179 1164 180 1152 17925 1 127 5

32 1 1/4 127 5H

435 1486 230 1474 228 1474 228 1474 228

25 1 127 5

32 1 1/4 127 5H

51 2 178 7

485 1847 286 1835 284 1828 283 1835 284

25 1 127 5

32 1 1/4 127 5H

51 2 178 7

535 2248 348 2235 347 2228 345 2235 347

25 1 127 5

32 1 1/4 127 5H

51 2 178 7

585 2688 417 2660 412 2660 412 2660 41232 1 1/4 127 5H

51 2 178 7

635 3167 491 3139 487 3139 487 3139 48732 1 1/4 127 5H

51 2 178 7

685 3685 571 3657 567 3657 567 3657 56732 1 1/4 127 5H

51 2 178 7


Table 5. 785C Double-Acting Spring Return Standard Constructions(1)

ACTUATORSIZE

PISTON AREA VALVE STEMCONNECTOR

SIZE

YOKE BOSSDIAMETER

AVAILABLE TRAVELWithout Manual Override With Manual Override(2)

Rod Extends Rod Retracts Rod Extends Rod Retracts

cm2 Inch2 cm2 Inch2 cm2 Inch2 cm2 Inch2 mm Inch mm Inch mm Inch

280 615 95 603 95 615 95.44 603 9325 1 127 5

0-102 0-432 1 1/4 127 5H

335 881 137 869 135 881 137 868 13525 1 127 5

0-203 0-832 1 1/4 127 5H

385 1164 180 1152 179 1164 180 1151 179

25 1 127 5

0-305 0-1232 1 1/4 127 5H

51 2 178 7

435 1486 230 1474 228 1474 228 1473 228

25 1 127 5

0-406 0-16

32 1 1/4 127 5H

51 2 178 7

485 1847 286 1835 284 1828 283 1834 284

25 1 127 5

32 1 1/4 127 5H

51 2 178 7

535 2248 348 2235 347 2228 345 2235 347

25 1 127 5

32 1 1/4 127 5H

51 2 178 7

585 2688 417 2660 412 2660 412 2659 41232 1 1/4 127 5H

51 2 178 7

635 3167 491 3139 487 3139 487 3138 48732 1 1/4 127 5H

51 2 178 7

685 3685 571 3657 567 3657 567 3657 56732 1 1/4 127 5H

51 2 178 7


https://www.emerson.com/en-us/contact-ushttps://www.emerson.com/en-us/contact-us



6

Table 6. Handwheel Specification

ACTUATORSIZE

OUTPUT THRUST HANDWHEEL DIAMETER TURNS PER mmOF TRAVEL

TURNS PER INCHOF TRAVEL

MAXIMUM RIMFORCE REQUIRED

N lbs mm Inch N lbs

280 32635 7337 850 33 0.2 4.2 437 98

335 46715 10502 1200 47 0.2 4.2 435 98

385 61700 13871 1400 55 0.2 4.2 489 110

Table 7. Handpump Specification

ACTUATOR SIZEHYDRAULIC CYLINDER OUTPUT THRUST

mm Inch N lbf

435 135 5.3 78726 17698

485 175 6.9 132291 29740

535 175 6.9 132291 29740

585 200 7.9 172788 38844

635 200 7.9 172788 38844

685 235 9.3 238555 53629

Table 8. Pressure Connections(1)

ACTUATOR SIZESTANDARD

Pressure Connection Size, NPT(Top)/(Bottom)

OPTIONALPressure Connection Size, NPT

(Top)/(Bottom)

QUANTITY(Top/Bottom)

280(2) (3/4) / (3/4) (3/4) / (3/4)

3/3

335(2) (3/4) / (3/4) (1) / (3/4)

385 (3/4) / (3/4) (1 1/4) / (3/4)

435 (3/4) / (3/4) (1 1/4) / (3/4)

485 to 685 (3/4) / (3/4) (1 1/4) / (1 1/4)

1. All bottom pressure connections are side tapped. All top pressure connections are face tapped.2. With use of top-mounted handwheel, all top and bottom pressure connections are side tapped for size 280 and 335 actuators.



7

Figure 2. Fisher 785C Double-Acting Springless Piston Actuator (see table 9 and 10)

FRONT VIEW

W

SECTION D-D

Z

A

A1

A3

G

AR

D D

GH10535

TOP VIEW

B

C

Table 9. 785C Double-Acting Springless Dimensions A, A1, A3, B, C, and GACTU-ATORSIZE

YOKEBOSS,Inch

MAX TRAVEL A A1 A3 B C G(1)

mm Inch mm Inch mm Inch mm Inch mm Inch mm Inch mm Inch

280 5 or 5H

102 4 739 29.1 438 17.2 245 9.6 419 16.5 419 16.5 369.5 14.5

203 8 926 36.5 524 20.6 346 13.6 419 16.5 419 16.5 463 18.2

305 12 1168 46 664 26.1 448 17.6 419 16.5 419 16.5 584 23

406 16 1372 54 766 30.2 550 21.7 419 16.5 419 16.5 686 27

508 20 1574 62 867 34.1 651 25.6 419 16.5 419 16.5 787 31

610 24 1778 70 969 38.1 753 29.6 419 16.5 419 16.5 889 35

335 5 or 5H

102 4 742 29.2 438 17.2 248 9.8 472 18.6 472 18.6 371 14.6

203 8 929 36.6 524 20.6 349 13.7 472 18.6 472 18.6 464.5 18.3

305 12 1171 46.1 664 26.1 451 17.8 472 18.6 472 18.6 585.5 23.1

406 16 1375 54.1 766 30.2 553 21.8 472 18.6 472 18.6 687.5 27.1

508 20 1577 62.1 867 34.1 654 25.7 472 18.6 472 18.6 788.5 31.0

610 24 1781 70.1 969 38.1 756 29.8 472 18.6 472 18.6 890.5 35.1

‐continued‐



8

Table 9. 785C Double-Acting Springless Dimensions A, A1, A3, B, C, and G (cont.)

ACTU-ATORSIZE

YOKEBOSS,Inch



385

5 or 5H

102 4 742 29.2 438 17.2 248 9.8 519 20.4 519 20.4 371 14.6

203 8 929 36.6 524 20.6 349 13.7 519 20.4 519 20.4 464.5 18.3

305 12 1171 46.1 664 26.1 451 17.8 519 20.4 519 20.4 585.5 23.1

406 16 1375 54.1 766 30.2 553 21.8 519 20.4 519 20.4 687.5 27.1

508 20 1577 62.1 867 34.1 654 25.7 519 20.4 519 20.4 788.5 31.0

610 24 1782 70.2 970 38.2 756 29.8 519 20.4 519 20.4 891 35.1

7

102 4 774 30.5 470 18.5 248 9.8 519 20.4 519 20.4 387 15.2

203 8 1005 39.6 600 23.6 349 13.7 519 20.4 519 20.4 502.5 19.8

305 12 1171 46.1 664 26.1 451 17.8 519 20.4 519 20.4 585.5 23.1

406 16 1375 54.1 766 30.2 553 21.8 519 20.4 519 20.4 687.5 27.1

508 20 1577 62.1 867 34.1 654 25.7 519 20.4 519 20.4 788.5 31.0

610 24 1780 70.1 968 38.1 756 29.8 519 20.4 519 20.4 890 35.0

435

5 or 5H

102 4 742 29.2 438 17.2 248 9.8 572 22.5 572 22.5 371 14.6

203 8 929 36.6 524 20.6 349 13.7 572 22.5 572 22.5 464.5 18.3

305 12 1171 46.1 664 26.1 451 17.8 572 22.5 572 22.5 585.5 23.1

406 16 1375 54.1 766 30.2 553 21.8 572 22.5 572 22.5 687.5 27.1

508 20 1577 62.1 867 34.1 654 25.7 572 22.5 572 22.5 788.5 31.0

610 24 1782 70.2 970 38.2 756 29.8 572 22.5 572 22.5 891 35.1

7

102 4 774 30.5 470 18.5 248 9.8 572 22.5 572 22.5 387 15.2

203 8 1005 39.6 600 23.6 349 13.7 572 22.5 572 22.5 502.5 19.8

305 12 1171 46.1 664 26.1 451 17.8 572 22.5 572 22.5 585.5 23.1

406 16 1375 54.1 766 30.2 553 21.8 572 22.5 572 22.5 687.5 27.1

508 20 1577 62.1 867 34.1 654 25.7 572 22.5 572 22.5 788.5 31.0

610 24 1780 70.1 968 38.1 756 29.8 572 22.5 572 22.5 890 35.0

485

5 or 5H

102 4 790 31.1 438 17.2 276 10.9 636 25.0 636 25.0 395 15.6

203 8 977 38.5 524 20.6 377 14.8 636 25.0 636 25.0 488.5 19.2

305 12 1219 48.0 664 26.1 479 18.9 636 25.0 636 25.0 609.5 24.0

406 16 1423 56.0 766 30.2 581 22.9 636 25.0 636 25.0 711.5 28.0

508 20 1625 64.0 867 34.1 682 26.9 636 25.0 636 25.0 812.5 32.0

610 24 1830 72.0 970 38.2 784 30.9 636 25.0 636 25.0 915 36.0

7

102 4 822 32.4 470 18.5 276 10.9 636 25.0 636 25.0 411 16.2

203 8 1053 41.5 600 23.6 377 14.8 636 25.0 636 25.0 526.5 20.7

305 12 1219 48.0 664 26.1 479 18.9 636 25.0 636 25.0 609.5 24.0

406 16 1423 56.0 766 30.2 581 22.9 636 25.0 636 25.0 711.5 28.0

508 20 1625 64.0 867 34.1 682 26.9 636 25.0 636 25.0 812.5 32.0

610 24 1828 72.0 968 38.1 784 30.9 636 25.0 636 25.0 914 36.0

535

5 or 5H

102 4 792 31.2 438 17.2 278 10.9 684 26.9 694 27.3 396 15.6

203 8 979 38.5 524 20.6 379 14.9 684 26.9 694 27.3 489.5 19.3

305 12 1221 48.1 664 26.1 481 18.9 684 26.9 694 27.3 610.5 24.0

406 16 1425 56.1 766 30.2 583 23.0 684 26.9 694 27.3 712.5 28.1

508 20 1627 64.1 867 34.1 684 26.9 684 26.9 694 27.3 813.5 32.0

610 24 1832 72.1 970 38.2 786 30.9 684 26.9 694 27.3 916 36.1

7

102 4 824 32.4 470 18.5 278 10.9 684 26.9 694 27.3 412 16.2

203 8 1055 41.5 600 23.6 379 14.9 684 26.9 694 27.3 527.5 20.8

305 12 1221 48.1 664 26.1 481 18.9 684 26.9 694 27.3 610.5 24.0

406 16 1425 56.1 766 30.2 583 23.0 684 26.9 694 27.3 712.5 28.1

508 20 1627 64.1 867 34.1 684 26.9 684 26.9 694 27.3 813.5 32.0

610 24 1830 72.0 968 38.1 786 30.9 684 26.9 694 27.3 915 36.0

‐continued‐



9

Table 9. 785C Double-Acting Springless Dimensions A, A1, A3, B, C, and G (cont.)

ACTU-ATORSIZE

YOKEBOSS,Inch



585

5H

102 4 833 32.8 461 18.1 296 11.7 737 29.0 750 29.5 416.5 16.4

203 8 1020 40.2 547 21.5 397 15.6 737 29.0 750 29.5 510 20.1

305 12 1262 49.7 687 27.0 499 19.6 737 29.0 750 29.5 631 24.8

406 16 1466 57.7 789 31.1 601 23.7 737 29.0 750 29.5 733 28.9

508 20 1668 65.7 890 35.0 702 27.6 737 29.0 750 29.5 834 32.8

610 24 1872 73.7 992 39.1 804 31.7 737 29.0 750 29.5 936 36.9

7

102 4 862 33.9 490 19.3 296 11.7 737 29.0 750 29.5 431 17.0

203 8 1093 43.0 620 24.4 397 15.6 737 29.0 750 29.5 546.5 21.5

305 12 1259 49.6 684 26.9 499 19.6 737 29.0 750 29.5 629.5 24.8

406 16 1462 57.6 785 30.9 601 23.7 737 29.0 750 29.5 731 28.8

508 20 1665 65.6 887 34.9 702 27.6 737 29.0 750 29.5 832.5 32.8

610 24 1869 73.6 989 38.9 804 31.7 737 29.0 750 29.5 934.5 36.8

635

5H

102 4 833 32.8 461 18.1 296 11.7 779 30.7 799 31.5 416.5 16.4

203 8 1020 40.2 547 21.5 397 15.6 779 30.7 799 31.5 510 20.1

305 12 1262 49.7 687 27.0 499 19.6 779 30.7 799 31.5 631 24.8

406 16 1466 57.7 789 31.1 601 23.7 779 30.7 799 31.5 733 28.9

508 20 1668 65.7 890 35.0 702 27.6 779 30.7 799 31.5 834 32.8

610 24 1872 73.7 992 39.1 804 31.7 779 30.7 799 31.5 936 36.9

7

102 4 862 33.9 490 19.3 296 11.7 779 30.7 799 31.5 431 17.0

203 8 1093 43.0 620 24.4 397 15.6 779 30.7 799 31.5 546.5 21.5

305 12 1259 49.6 684 26.9 499 19.6 779 30.7 799 31.5 629.5 24.8

406 16 1462 57.6 785 30.9 601 23.7 779 30.7 799 31.5 731 28.8

508 20 1665 65.6 887 34.9 702 27.6 779 30.7 799 31.5 832.5 32.8

610 24 1869 73.6 989 38.9 804 31.7 779 30.7 799 31.5 934.5 36.8

685

5H

102 4 868 34.2 486 19.1 306 12.0 832 32.8 855 33.7 434 17.1

203 8 1055 41.5 572 22.5 407 16.0 832 32.8 855 33.7 527.5 20.8

305 12 1297 51.1 712 28.0 509 20.0 832 32.8 855 33.7 648.5 25.5

406 16 1501 59.1 814 32.0 611 24.1 832 32.8 855 33.7 750.5 29.5

508 20 1703 67.0 915 36.0 712 28.0 832 32.8 855 33.7 851.5 33.5

610 24 1907 75.1 1017 40.0 814 32.0 832 32.8 855 33.7 953.5 37.5

7

102 4 897 35.3 515 20.3 306 12.0 832 32.8 855 33.7 448.5 17.7

203 8 1128 44.4 645 25.4 407 16.0 832 32.8 855 33.7 564 22.2

305 12 1294 50.9 709 27.9 509 20.0 832 32.8 855 33.7 647 25.5

406 16 1497 58.9 810 31.9 611 24.1 832 32.8 855 33.7 748.5 29.5

508 20 1700 66.9 912 35.9 712 28.0 832 32.8 855 33.7 850 33.5

610 24 1904 75.0 1014 39.9 814 32.0 832 32.8 855 33.7 952 37.5

1. Center of Gravity

Table 10. 785C Double-Acting Springless Dimension Z and W

ACTUATORSIZE

WITHOUT MANUAL OVERRIDE WITH MANUAL OVERRIDE

Z W Z W

5, 5H, or 7 Inch Yoke Boss 5, 5H, or 7 Inch Yoke Boss

mm Inch mm Inch mm Inch mm Inch

280 254 10 292 11.5 254 10 292 11.5

335 254 10 292 11.5 254 10 292 11.5

385 330 13 330 13 330 13 330 13

435 330 13 330 13 330 13 330 13

485 330 13 330 13 330 13 330 13

535 330 13 330 13 330 13 330 13

585 487 19.2 436 17.2 487 19.2 436 17.2

635 487 19.2 436 17.2 487 19.2 436 17.2

685 487 19.2 436 17.2 487 19.2 436 17.2



10

Table 11. 785C Double-Acting Springless with Manual Override Dimensions A, A1, A3, A4, and G

ACTU-ATORSIZE

YOKEBOSS,Inch

MANUALOVERRIDE

MAX TRAVEL A A1 A3 A4 G(1)

mm Inch mm Inch mm Inch mm Inch mm Inch mm Inch

280 5 or 5H

HandWheel

102 4 1024 40.3 438 17.2 296 11.7 290 11.4 512 20.2

203 8 1312 51.7 524 20.6 397 15.6 391 15.4 656 25.8

305 12 1655 65.2 664 26.1 499 19.6 492 19.4 827.5 32.6

406 16 1960 77.2 766 30.2 601 23.7 593 23.3 980 38.6

508 20 2263 89.1 867 34.1 702 27.6 694 27.3 1131.5 44.5

610 24 2568 101.1 969 38.1 804 31.7 795 31.3 1284 50.6

335 5 or 5H

102 4 1031 40.6 438 17.2 302.5 11.9 290 11.4 515.25 20.3

203 8 1319 51.9 524 20.6 403.5 15.9 391 15.4 659.25 26.0

305 12 1662 65.4 664 26.1 505.5 19.9 492 19.4 830.75 32.7

406 16 1967 77.4 766 30.2 607.5 23.9 593 23.3 983.25 38.7

508 20 2270 89.4 867 34.1 708.5 27.9 694 27.3 1134.7 44.7

610 24 2575 101.4 969 38.1 810.5 31.9 795 31.3 1287.2 50.7

385

5 or 5H

102 4 1013 39.9 438 17.2 285 11.2 290 11.4 506.5 19.9

203 8 1301 51.2 524 20.6 386 15.2 391 15.4 650.5 25.6

305 12 1644 64.7 664 26.1 488 19.2 492 19.4 822 32.4

406 16 1949 76.7 766 30.2 590 23.2 593 23.3 974.5 38.4

508 20 2252 88.7 867 34.1 691 27.2 694 27.3 1126 44.3

610 24 2558 100.7 970 38.2 793 31.2 795 31.3 1279 50.4

7

102 4 1045 41.1 470 18.5 285 11.2 290 11.4 522.5 20.6

203 8 1377 54.2 600 23.6 386 15.2 391 15.4 688.5 27.1

305 12 1644 64.7 664 26.1 488 19.2 492 19.4 822 32.4

406 16 1949 76.7 766 30.2 590 23.2 593 23.3 974.5 38.4

508 20 2252 88.7 867 34.1 691 27.2 694 27.3 1126 44.3

610 24 2556 100.6 968 38.1 793 31.2 795 31.3 1278 50.3

435

5 or 5H

Hand Pump

102 4 1095 43.1 438 17.2 282 11.1 375 14.8 547.5 21.6

203 8 1403 55.2 524 20.6 383 15.1 496 19.5 701.5 27.6

305 12 1746 68.7 664 26.1 485 19.1 597 23.5 873 34.4

406 16 2051 80.7 766 30.2 587 23.1 698 27.5 1025.5 40.4

508 20 2354 92.7 867 34.1 688 27.1 799 31.5 1177 46.3

610 24 2660 104.7 970 38.2 790 31.1 900 35.4 1330 52.4

7

102 4 1127 44.4 470 18.5 282 11.1 375 14.8 563.5 22.2

203 8 1479 58.2 600 23.6 383 15.1 496 19.5 739.5 29.1

305 12 1746 68.7 664 26.1 485 19.1 597 23.5 873 34.4

406 16 2051 80.7 766 30.2 587 23.1 698 27.5 1025.5 40.4

508 20 2354 92.7 867 34.1 688 27.1 799 31.5 1177 46.3

610 24 2658 104.6 968 38.1 790 31.1 900 35.4 1329 52.3

485

5 or 5H

102 4 1126 44.3 438 17.2 313 12.3 375 14.8 563 22.2

203 8 1434 56.5 524 20.6 414 16.3 496 19.5 717 28.2

305 12 1777 70.0 664 26.1 516 20.3 597 23.5 888.5 35.0

406 16 2082 82.0 766 30.2 618 24.3 698 27.5 1041 41.0

508 20 2385 93.9 867 34.1 719 28.3 799 31.5 1192.5 46.9

610 24 2691 105.9 970 38.2 821 32.3 900 35.4 1345.5 53.0

7

102 4 1158 45.6 470 18.5 313 12.3 375 14.8 579 22.8

203 8 1510 59.4 600 23.6 414 16.3 496 19.5 755 29.7

305 12 1777 70.0 664 26.1 516 20.3 597 23.5 888.5 35.0

406 16 2082 82.0 766 30.2 618 24.3 698 27.5 1041 41.0

508 20 2385 93.9 867 34.1 719 28.3 799 31.5 1192.5 46.9

610 24 2689 105.9 968 38.1 821 32.3 900 35.4 1344.5 52.9‐continued‐



11

Table 11. 785C Double-Acting Springless with Manual Override Dimensions A, A1, A3, A4, and G (cont.)

ACTU-ATORSIZE

YOKEBOSS,Inch

MANUALOVERRIDE

MAX TRAVEL A A1 A3 A4 G(1)


535

5 or 5H

Hand Pump

102 4 1130 44.5 438 17.2 317 12.5 375 14.8 565 22.2

203 8 1438 56.6 524 20.6 418 16.5 496 19.5 719 28.3

305 12 1781 70.1 664 26.1 520 20.5 597 23.5 890.5 35.1

406 16 2086 82.1 766 30.2 622 24.5 698 27.5 1043 41.1

508 20 2389 94.1 867 34.1 723 28.5 799 31.5 1194.5 47.0

610 24 2695 106.1 970 38.2 825 32.5 900 35.4 1347.5 53.1

7

102 4 1162 45.7 470 18.5 317 12.5 375 14.8 581 22.9

203 8 1514 59.6 600 23.6 418 16.5 496 19.5 757 29.8

305 12 1781 70.1 664 26.1 520 20.5 597 23.5 890.5 35.1

406 16 2086 82.1 766 30.2 622 24.5 698 27.5 1043 41.1

508 20 2389 94.1 867 34.1 723 28.5 799 31.5 1194.5 47.0

610 24 2693 106.0 968 38.1 825 32.5 900 35.4 1346.5 53.0

585

5H

102 4 1201 47.3 461 18.1 348 13.7 392 15.4 600.5 23.6

203 8 1509 59.4 547 21.5 449 17.7 513 20.2 754.5 29.7

305 12 1852 72.9 687 27.0 551 21.7 614 24.2 926 36.5

406 16 2157 84.9 789 31.1 653 25.7 715 28.1 1078.5 42.5

508 20 2460 96.9 890 35.0 754 29.7 816 32.1 1230 48.4

610 24 2765 108.9 992 39.1 856 33.7 917 36.1 1382.5 54.4

7

102 4 1230 48.4 490 19.3 348 13.7 392 15.4 615 24.2

203 8 1582 62.3 620 24.4 449 17.7 513 20.2 791 31.1

305 12 1849 72.8 684 26.9 551 21.7 614 24.2 924.5 36.4

406 16 2153 84.8 785 30.9 653 25.7 715 28.1 1076.5 42.4

508 20 2457 96.7 887 34.9 754 29.7 816 32.1 1228.5 48.4

610 24 2762 108.7 989 38.9 856 33.7 917 36.1 1381 54.4

635

5H

102 4 1202 47.3 461 18.1 349 13.7 392 15.4 601 23.7

203 8 1510 59.4 547 21.5 450 17.7 513 20.2 755 29.7

305 12 1853 73.0 687 27.0 552 21.7 614 24.2 926.5 36.5

406 16 2158 85.0 789 31.1 654 25.7 715 28.1 1079 42.5

508 20 2461 96.9 890 35.0 755 29.7 816 32.1 1230.5 48.4

610 24 2766 108.9 992 39.1 857 33.7 917 36.1 1383 54.4

7

102 4 1231 48.5 490 19.3 349 13.7 392 15.4 615.5 24.2

203 8 1583 62.3 620 24.4 450 17.7 513 20.2 791.5 31.2

305 12 1850 72.8 684 26.9 552 21.7 614 24.2 925 36.4

406 16 2154 84.8 785 30.9 654 25.7 715 28.1 1077 42.4

508 20 2458 96.8 887 34.9 755 29.7 816 32.1 1229 48.4

610 24 2763 108.8 989 38.9 857 33.7 917 36.1 1381.5 54.4

685

5H

102 4 1251 49.3 486 19.1 373 14.7 392 15.4 625.5 24.6

203 8 1559 61.4 572 22.5 474 18.7 513 20.2 779.5 30.7

305 12 1902 74.9 712 28.0 576 22.7 614 24.2 951 37.4

406 16 2207 86.9 814 32.0 678 26.7 715 28.1 1103.5 43.4

508 20 2510 98.8 915 36.0 779 30.7 816 32.1 1255 49.4

610 24 2815 110.8 1017 40.0 881 34.7 917 36.1 1407.5 55.4

7

102 4 1280 50.4 515 20.3 373 14.7 392 15.4 640 25.2

203 8 1632 64.3 645 25.4 474 18.7 513 20.2 816 32.1

305 12 1899 74.8 709 27.9 576 22.7 614 24.2 949.5 37.4

406 16 2203 86.7 810 31.9 678 26.7 715 28.1 1101.5 43.4

508 20 2507 98.7 912 35.9 779 30.7 816 32.1 1253.5 49.4

610 24 2812 110.7 1014 39.9 881 34.7 917 36.1 1406 55.4

1. Center of Gravity



12

Table 12. 785C Double-Acting Springless with Manual Override Dimensions B, B1, C, and C1

ACTUATORSIZE

YOKEBOSS,Inch

MANUALOVERRIDE

MAX TRAVEL B B1 C C1

mm Inch mm Inch mm Inch mm Inch mm Inch

280 5 or 5H

Hand Wheel

102 4 850 33.5 419 16.5 464 18.3 - - - - - -

203 8 850 33.5 419 16.5 464 18.3 - - - - - -

305 12.0 850 33.5 419 16.5 464 18.3 - - - - - -

406 16.0 850 33.5 419 16.5 464 18.3 - - - - - -

508 20.0 850 33.5 419 16.5 464 18.3 - - - - - -

610 24.0 850 33.5 419 16.5 464 18.3 - - - - - -

335 5 or 5H

102 4 1250 49.2 472 18.6 517 20.4 - - - - - -

203 8 1250 49.2 472 18.6 517 20.4 - - - - - -

305 12.0 1250 49.2 472 18.6 517 20.4 - - - - - -

406 16.0 1250 49.2 472 18.6 517 20.4 - - - - - -

508 20.0 1250 49.2 472 18.6 517 20.4 - - - - - -

610 24.0 1250 49.2 472 18.6 517 20.4 - - - - - -

385

5 or 5H

102 4 1400 55.1 519 20.4 846 33.3 - - - - - -

203 8 1400 55.1 519 20.4 846 33.3 - - - - - -

305 12.0 1400 55.1 519 20.4 846 33.3 - - - - - -

406 16.0 1400 55.1 519 20.4 846 33.3 - - - - - -

508 20.0 1400 55.1 519 20.4 846 33.3 - - - - - -

610 24.0 1400 55.1 519 20.4 846 33.3 - - - - - -

7

102 4 1400 55.1 519 20.4 846 33.3 - - - - - -

203 8 1400 55.1 519 20.4 846 33.3 - - - - - -

305 12.0 1400 55.1 519 20.4 846 33.3 - - - - - -

406 16.0 1400 55.1 519 20.4 846 33.3 - - - - - -

508 20.0 1400 55.1 519 20.4 846 33.3 - - - - - -

610 24.0 1400 55.1 519 20.4 846 33.3 - - - - - -

435

5 or 5H

Hand Pump

102 4 908 35.7 572 22.5 846 33.3 565 22.2

203 8 908 35.7 572 22.5 846 33.3 565 22.2

305 12.0 908 35.7 572 22.5 846 33.3 565 22.2

406 16.0 908 35.7 572 22.5 846 33.3 565 22.2

508 20.0 908 35.7 572 22.5 846 33.3 565 22.2

610 24.0 908 35.7 572 22.5 846 33.3 565 22.2

7

102 4 908 35.7 572 22.5 846 33.3 565 22.2

203 8 908 35.7 572 22.5 846 33.3 565 22.2

305 12.0 908 35.7 572 22.5 846 33.3 565 22.2

406 16.0 908 35.7 572 22.5 846 33.3 565 22.2

508 20.0 908 35.7 572 22.5 846 33.3 565 22.2

610 24.0 908 35.7 572 22.5 846 33.3 565 22.2

485

5 or 5H

102 4 940 37.0 636 25.0 858 33.8 630 24.8

203 8 940 37.0 636 25.0 858 33.8 630 24.8

305 12.0 940 37.0 636 25.0 858 33.8 630 24.8

406 16.0 940 37.0 636 25.0 858 33.8 630 24.8

508 20.0 940 37.0 636 25.0 858 33.8 630 24.8

610 24.0 940 37.0 636 25.0 858 33.8 630 24.8

7

102 4 940 37.0 636 25.0 858 33.8 630 24.8

203 8 940 37.0 636 25.0 858 33.8 630 24.8

305 12.0 940 37.0 636 25.0 858 33.8 630 24.8

406 16.0 940 37.0 636 25.0 858 33.8 630 24.8

508 20.0 940 37.0 636 25.0 858 33.8 630 24.8

610 24.0 940 37.0 636 25.0 858 33.8 630 24.8‐continued‐



13

Table 12. 785C Double-Acting Springless with Manual Override Dimensions B, B1, C, and C1 (cont.)

ACTUATORSIZE

YOKEBOSS,Inch

MANUALOVERRIDE

MAX TRAVEL B B1 C C1

mm Inch mm Inch mm Inch mm Inch mm Inch

535

5 or 5H

Hand Pump

102 4 962 37.9 684 26.9 915 36.0 680 26.8

203 8 962 37.9 684 26.9 915 36.0 680 26.8

305 12.0 962 37.9 684 26.9 915 36.0 680 26.8

406 16.0 962 37.9 684 26.9 915 36.0 680 26.8

508 20.0 962 37.9 684 26.9 915 36.0 680 26.8

610 24.0 962 37.9 684 26.9 915 36.0 680 26.8

7

102 4 962 37.9 684 26.9 915 36.0 680 26.8

203 8 962 37.9 684 26.9 915 36.0 680 26.8

305 12.0 962 37.9 684 26.9 915 36.0 680 26.8

406 16.0 962 37.9 684 26.9 915 36.0 680 26.8

508 20.0 962 37.9 684 26.9 915 36.0 680 26.8

610 24.0 962 37.9 684 26.9 915 36.0 680 26.8

585

5H

102 4 1102 43.4 737 29.0 983 38.7 730 28.7

203 8 1102 43.4 737 29.0 983 38.7 730 28.7

305 12.0 1102 43.4 737 29.0 983 38.7 730 28.7

406 16.0 1102 43.4 737 29.0 983 38.7 730 28.7

508 20.0 1102 43.4 737 29.0 983 38.7 730 28.7

610 24.0 1102 43.4 737 29.0 983 38.7 730 28.7

7

102 4 1102 43.4 737 29.0 983 38.7 730 28.7

203 8 1102 43.4 737 29.0 983 38.7 730 28.7

305 12.0 1102 43.4 737 29.0 983 38.7 730 28.7

406 16.0 1102 43.4 737 29.0 983 38.7 730 28.7

508 20.0 1102 43.4 737 29.0 983 38.7 730 28.7

610 24.0 1102 43.4 737 29.0 983 38.7 730 28.7

635

5H

102 4 1127 44.4 779 30.7 1007 39.6 785 30.9

203 8 1127 44.4 779 30.7 1007 39.6 785 30.9

305 12.0 1127 44.4 779 30.7 1007 39.6 785 30.9

406 16.0 1127 44.4 779 30.7 1007 39.6 785 30.9

508 20.0 1127 44.4 779 30.7 1007 39.6 785 30.9

610 24.0 1127 44.4 779 30.7 1007 39.6 785 30.9

7

102 4 1127 44.4 779 30.7 1007 39.6 785 30.9

203 8 1127 44.4 779 30.7 1007 39.6 785 30.9

305 12.0 1127 44.4 779 30.7 1007 39.6 785 30.9

406 16.0 1127 44.4 779 30.7 1007 39.6 785 30.9

508 20.0 1127 44.4 779 30.7 1007 39.6 785 30.9

610 24.0 1127 44.4 779 30.7 1007 39.6 785 30.9

685

5H

102 4 1153 45.4 832 32.8 1035 40.7 840 33.1

203 8 1153 45.4 832 32.8 1035 40.7 840 33.1

305 12.0 1153 45.4 832 32.8 1035 40.7 840 33.1

406 16.0 1153 45.4 832 32.8 1035 40.7 840 33.1

508 20.0 1153 45.4 832 32.8 1035 40.7 840 33.1

610 24.0 1153 45.4 832 32.8 1035 40.7 840 33.1

7

102 4 1153 45.4 832 32.8 1035 40.7 840 33.1

203 8 1153 45.4 832 32.8 1035 40.7 840 33.1

305 12.0 1153 45.4 832 32.8 1035 40.7 840 33.1

406 16.0 1153 45.4 832 32.8 1035 40.7 840 33.1

508 20.0 1153 45.4 832 32.8 1035 40.7 840 33.1

610 24.0 1153 45.4 832 32.8 1035 40.7 840 33.1



14

Figure 3. Fisher 785C Double-Acting Springless Piston Actuator with Handwheel (see table 11 and 12)

FRONT VIEW

W

SECTION D-D

Z

A4

A

A3

G

AR

DD

A1

TOP VIEW

B1

C

�B

GH1537

Figure 4. Fisher 785C Double-Acting Springless Piston Actuator with Hand Pump (see table 11 and 12)

FRONT VIEW

W

SECTION D-D

Z

A4

A A3

G

AR

B1

B

A1

TOP VIEW

DD

C

C1

GH10538



15

Figure 5. Fisher 785C Single-Acting Spring Return Piston Actuator (see table 13, 16, and 19)

FRONT VIEW

W

SECTION D-D

Z

A2

A

A3

G

AR

D D

A1

TOP VIEW

B

C

GH10536



16

Table 13. 785C Single-Acting and Double Acting Spring Return (Spring Retracts) Dimensions A, A1, A2, A3, B, C, and G(1)

ACTU-ATORSIZE

YOKEBOSS,Inch

MAX TRAVEL A A1 A2 A3 G(2) B C

mm Inch mm Inch mm Inch mm Inch mm Inch mm Inch mm Inch mm Inch

385

5 or 5H

102 4 1227 48.3 438 17.2 485 19.1 248 9.8 614 24.2 519 20.4 519 20.4

203 8 1516 59.7 524 20.6 587 23.1 349 13.7 758 29.8 519 20.4 519 20.4

318 12 2281 89.8 664 26.1 1110 43.7 451 17.8 1141 44.9 451 17.8 519 20.4

7

102 4 1259 49.6 438 17.2 485 19.1 248 9.8 630 24.8 519 20.4 519 20.4

203 8 1592 62.7 524 20.6 587 23.1 349 13.7 796 31.3 519 20.4 519 20.4

318 12 2281 89.8 664 26.1 1110 43.7 451 17.8 1141 44.9 519 20.4 519 20.4

435

5 or 5H

102 4 1262 49.7 438 17.2 520 20.5 248 9.8 631 24.8 572 22.5 572 22.5

203 8 1702 67.0 524 20.6 773 30.4 349 13.7 851 33.5 572 22.5 572 22.5

318 12 2206 86.9 664 26.1 1035 40.7 451 17.8 1103 43.4 572 22.5 572 22.5

420 16 2507 98.7 766 30.2 1132 44.6 553 21.8 1254 49.4 572 22.5 572 22.5

7

102 4 1294 50.9 438 17.2 520 20.5 248 9.8 647 25.5 572 22.5 572 22.5

203 8 1778 70.0 524 20.6 773 30.4 349 13.7 889 35.0 572 22.5 572 22.5

318 12 2206 86.9 664 26.1 1035 40.7 451 17.8 1103 43.4 572 22.5 572 22.5

420 16 2507 98.7 766 30.2 1132 44.6 553 21.8 1254 49.4 572 22.5 572 22.5

485

5 or 5H

102 4 1354 53.3 438 17.2 564 22.2 276 10.9 677 26.7 636 25.0 636 25.0

203 8 1749 68.9 524 20.6 772 30.4 377 14.8 874.5 34.4 636 25.0 636 25.0

318 12 2252 88.7 664 26.1 1033 40.7 479 18.9 1126 44.3 636 25.0 636 25.0

420 16 2548 100.3 766 30.2 1125 44.3 581 22.9 1274 50.2 636 25.0 636 25.0

7

102 4 1386 54.6 438 17.2 564 22.2 276 10.9 693 27.3 636 25.0 636 25.0

203 8 1825 71.9 524 20.6 772 30.4 377 14.8 912.5 35.9 636 25.0 636 25.0

318 12 2252 88.7 664 26.1 1033 40.7 479 18.9 1126 44.3 636 25.0 636 25.0

420 16 2548 100.3 766 30.2 1125 44.3 581 22.9 1274 50.2 636 25.0 636 25.0

535

5 or 5H

102 4 1336 52.6 438 17.2 544 21.4 278 10.9 668 26.3 684 26.9 694 27.3

203 8 1806 71.1 524 20.6 827 32.6 379 14.9 903 35.6 684 26.9 694 27.3

318 12 2216 87.2 664 26.1 995 39.2 481 18.9 1108 43.6 684 26.9 694 27.3

420 16 2469 97.2 766 30.2 1004 39.5 583 23.0 1235 48.6 684 26.9 694 27.3

7

102 4 1368 53.9 438 17.2 544 21.4 278 10.9 684 26.9 684 26.9 694 27.3

203 8 1882 74.1 524 20.6 827 32.6 379 14.9 941 37.0 684 26.9 694 27.3

318 12 2216 87.2 664 26.1 995 39.2 481 18.9 1108 43.6 684 26.9 694 27.3

420 16 2469 97.2 766 30.2 1004 39.5 583 23.0 1235 48.6 684 26.9 694 27.3

585

5H

102 4 1370 53.9 438 17.2 537 21.1 296 11.7 685 27.0 737 29.0 750 29.5

203 8 1824 71.8 524 20.6 804 31.7 397 15.6 912 35.9 737 29.0 750 29.5

318 12 2284 89.9 687 27.0 1022 40.2 499 19.6 1142 45.0 737 29.0 750 29.5

420 16 2555 100.6 789 31.1 1089 42.9 601 23.7 1278 50.3 737 29.0 750 29.5

7

102 4 1399 55.1 438 17.2 537 21.1 296 11.7 699.5 27.5 737 29.0 750 29.5

203 8 1897 74.7 524 20.6 804 31.7 397 15.6 948.5 37.3 737 29.0 750 29.5

318 12 2281 89.8 684 26.9 1022 40.2 499 19.6 1141 44.9 737 29.0 750 29.5

420 16 2551 100.4 785 30.9 1089 42.9 601 23.7 1276 50.2 737 29.0 750 29.5

635

5H102 4 1355 53.3 438 17.2 522 20.6 296 11.7 677.5 26.7 779 30.7 799 31.5

203 8 1824 71.8 524 20.6 804 31.7 397 15.6 912 35.9 779 30.7 799 31.5

7102 4 1384 54.5 438 17.2 522 20.6 296 11.7 692 27.2 779 30.7 799 31.5

203 8 1897 74.7 524 20.6 804 31.7 397 15.6 948.5 37.3 779 30.7 799 31.5

685

5H102 4 1628 64.1 438 17.2 760 29.9 306 12.0 814 32.0 832 32.8 855 33.7

203 8 1864 73.4 524 20.6 809 31.9 407 16.0 932 36.7 832 32.8 855 33.7

7102 4 1657 65.2 438 17.2 760 29.9 306 12.0 829 32.6 832 32.8 855 33.7

203 8 1937 76.3 524 20.6 809 31.9 407 16.0 969 38.1 832 32.8 855 33.7

1. Dimensions are maximum2. Center of Gravity



17

Table 14. 785C Single-Acting and Double-Acting Spring Return (Spring Retracts) with Manual Override Dimensions A, A1, A2, A3, and A4(1)

ACTUATORSIZE

YOKEBOSS,Inch

ManualOverride

MAXTRAVEL

A A1 A2 A3 A4


280 5 or 5H

Hand Wheel

102 4 1483 58.4 438 17.2 643 25.3 296 11.7 290 11.4

203 8 1777 70.0 524 20.6 741 29.2 397 15.6 391 15.4

335 5 or 5H102 4 1403 55.2 438 17.2 516 20.3 302.5 11.9 290 11.4

203 8 1694 66.7 524 20.6 608 23.9 403.5 15.9 391 15.4

385

5 or 5H

102 4 1367.5 53.8 438 17.2 485 19.1 285 11.2 290 11.4

203 8 1669.6 65.7 524 20.6 587 23.1 386 15.2 391 15.4

318 12 2448 96.4 664 26.1 1110 43.7 488 19.2 492 19.4

7

102 4 1399.5 58.6 470 18.5 485 19.1 285 11.2 290 14.8

203 8 1745.6 76.6 600 23.6 587 23.1 386 15.2 391 19.5

318 12 2448 59.8 664 26.1 1110 43.7 488 19.2 492 14.8

435

5 or 5H

Hand Pump

102 4 1487.7 58.6 438 17.2 520 20.5 282 11.1 375 14.8

203 8 1946.8 76.6 524 20.6 773 30.4 383 15.1 496 19.5

318 12 2470 97.2 664 26.1 1035 40.7 485 19.1 597 23.5

420 16 2790 109.8 766 30.2 1132 44.6 587 23.1 698 27.5

7

102 4 1519.7 59.8 470 18.5 520 20.5 282 11.1 375 14.8

203 8 2022.8 79.6 600 23.6 773 30.4 383 15.1 496 19.5

318 12 2470 97.2 664 26.1 1035 40.7 485 19.1 597 23.5

420 16 2790 109.8 766 30.2 1132 44.6 587 23.1 698 27.5

485

5 or 5H

102 4 1675.2 66.0 438 17.2 564 22.2 313 12.3 375 14.8

203 8 2093.6 82.4 524 20.6 772 30.4 414 16.3 496 19.5

318 12 2620 103.1 664 26.1 1033 40.7 516 20.3 597 23.5

420 16 2940 115.7 766 30.2 1125 44.3 618 24.3 698 27.5

7

102 4 1707.2 67.2 470 18.5 564 22.2 313 12.3 375 14.8

203 8 2169.6 85.4 600 23.6 772 30.4 414 16.3 496 19.5

318 12 2620 103.1 664 26.1 1033 40.7 516 20.3 597 23.5

420 16 2940 115.7 766 30.2 1125 44.3 618 24.3 698 27.5

535

5 or 5H

102 4 1712.9 67.4 438 17.2 544 21.4 317 12.5 375 14.8

203 8 2208.7 87.0 524 20.6 827 32.6 418 16.5 496 19.5

318 12 2645 104.1 664 26.1 995 39.2 520 20.5 597 23.5

420 16 2924 115.1 766 30.2 1044 41.1 622 24.5 698 27.5

7

102 4 1744.9 68.7 470 18.5 544 21.4 317 12.5 375 14.8

203 8 2284.7 89.9 600 23.6 827 32.6 418 16.5 496 19.5

318 12 2645 104.1 664 26.1 827 32.6 418 16.5 496 19.5

420 16 2924 115.1 766 30.2 995 39.2 520 20.5 597 23.5

585

5H

102 4 1852 72.9 438 17.2 537 21.1 348 13.7 392 15.4

203 8 2336.6 92.0 524 20.6 804 31.7 449 17.7 513 20.2

318 12 2827 111.3 664 26.1 1022 40.2 551 21.7 614 24.2

420 16 3129 123.2 766 30.2 1089 42.9 653 25.7 715 28.1

7

102 4 1881 74.1 470 18.5 537 21.1 348 13.7 392 15.4

203 8 2409.6 94.9 600 23.6 804 31.7 449 17.7 513 20.2

318 12 2824 111.2 664 26.1 1022 40.2 551 21.7 614 24.2

420 16 3125 123.0 766 30.2 1089 42.9 653 25.7 715 28.1

635

5H102 4 1915 75.4 438 17.2 522 20.6 349 13.7 392 15.4

203 8 2420.8 95.3 524 20.6 804 31.7 450 17.7 513 20.2

7102 4 1944 76.5 470 18.5 522 20.6 349 13.7 392 15.4

203 8 2493.8 98.2 600 23.6 804 31.7 450 17.7 513 20.2

685

5H102 4 2354 92.7 438 17.2 760 29.9 373 14.7 392 15.4

203 8 2629.7 103.5 524 20.6 809 31.9 474 18.7 392 15.4

7102 4 2383 93.8 470 18.5 760 29.9 373 14.7 513 20.2

203 8 2702.7 106.4 600 23.6 809 31.9 474 18.7 513 20.2

1. Dimensions are maximum



18

Table 15. 785C Single-Acting and Double-Acting Spring Return (Spring Retracts) with Manual Override Dimensions B, B1, C, C1, and G(1)

ACTUATORSIZE

YOKEBOSS,Inch

ManualOverride

MAXTRAVEL

G(2) B B1 C C1


280 5 or 5H

Hand Wheel

102 4 741.5 29.2 850 33.5 419 16.5 464 18.3 - - - - - -

203 8 725 28.5 850 33.5 419 16.5 464 18.3 - - - - - -

335 5 or 5H102 4 846.7 33.3 1250 49.2 472 18.6 517 20.4 - - - - - -

203 8 701.4 27.6 1250 49.2 472 18.6 517 20.4 - - - - - -

385

5 or 5H

102 4 683.7 26.9 1400 55.1 519 20.4 564 22.2 - - - - - -

203 8 834.8 32.9 1400 55.1 519 20.4 564 22.2 - - - - - -

318 12 1224 48.2 1400 55.1 519 20.4 564 22.2 - - - - - -

7

102 4 699.7 27.5 1400 55.1 519 20.4 564 22.2 - - - - - -

203 8 872.8 34.4 1400 55.1 519 20.4 564 22.2 - - - - - -

318 12 1224 48.2 1400 55.1 519 20.4 564 22.2 - - - - - -

435

5 or 5H

Hand Pump

102 4 743.8 29.3 908 35.7 572 22.5 846 33.3 565 22.2

203 8 973.4 38.3 908 35.7 572 22.5 846 33.3 565 22.2

318 12 1235 48.6 908 35.7 572 22.5 846 33.3 565 22.2

420 16 1395 54.9 908 35.7 572 22.5 846 33.3 565 22.2

7

102 4 759.8 29.9 908 35.7 572 22.5 846 33.3 565 22.2

203 8 1011.4 39.8 908 35.7 572 22.5 846 33.3 565 22.2

318 12 1235 48.6 908 35.7 572 22.5 846 33.3 565 22.2

420 16 1395 54.9 908 35.7 572 22.5 846 33.3 565 22.2

485

5 or 5H

102 4 837.6 33.0 940 37.0 636 25.0 858 33.8 630 24.8

203 8 1046.8 41.2 940 37.0 636 25.0 858 33.8 630 24.8

318 12 1310 51.6 940 37.0 636 25.0 858 33.8 630 24.8

420 16 1470 57.9 940 37.0 636 25.0 858 33.8 630 24.8

7

102 4 853.6 33.6 940 37.0 636 25.0 858 33.8 630 24.8

203 8 1084.8 42.7 940 37.0 636 25.0 858 33.8 630 24.8

318 12 1310 51.6 940 37.0 636 25.0 858 33.8 630 24.8

420 16 1470 57.9 940 37.0 636 25.0 858 33.8 630 24.8

535

5 or 5H

102 4 856.4 33.7 962 37.9 684 26.9 915 36.0 680 26.8

203 8 1104.3 43.5 962 37.9 684 26.9 915 36.0 680 26.8

318 12 1322 52.0 962 37.9 685 27.0 916 36.1 681 26.8

420 16 1462 57.6 962 37.9 686 27.0 917 36.1 682 26.9

7

102 4 872.45 34.3 962 37.9 687 27.0 918 36.1 683 26.9

203 8 1142.3 45.0 962 37.9 688 27.1 919 36.2 684 26.9

318 12 1322 52.0 962 37.9 689 27.1 920 36.2 685 27.0

420 16 1462 57.6 962 37.9 690 27.2 921 36.3 686 27.0

585

5H

102 4 926 36.5 1102 43.4 737 29.0 983 38.7 730 28.7

203 8 1168.3 46.0 1102 43.4 737 29.0 983 38.7 730 28.7

318 12 1414 55.7 1102 43.4 738 29.1 984 38.7 731 28.8

420 16 1565 61.6 1102 43.4 739 29.1 985 38.8 732 28.8

7

102 4 940.5 37.0 1102 43.4 740 29.1 986 38.8 733 28.9

203 8 1204.8 47.4 1102 43.4 741 29.2 987 38.9 734 28.9

318 12 1412 55.6 1102 43.4 742 29.2 988 38.9 735 28.9

420 16 1563 61.5 1102 43.4 743 29.3 989 38.9 736 29.0

635

5H102 4 957.5 37.7 1127 44.4 779 30.7 1007 39.6 785 30.9

203 8 1210.4 47.7 1127 44.4 779 30.7 1007 39.6 785 30.9

7102 4 972 38.3 1127 44.4 782 30.8 1010 39.8 788 31.0

203 8 1246.9 49.1 1127 44.4 783 30.8 1011 39.8 789 31.1

685

5H102 4 1177 46.3 1153 45.4 832 32.8 1035 40.7 840 33.1

203 8 1314.8 51.8 1153 45.4 832 32.8 1035 40.7 840 33.1

7102 4 1191.5 46.9 1153 45.4 835 32.9 1038 40.9 843 33.2

203 8 1351.3 53.2 1153 45.4 836 32.9 1039 40.9 844 33.2




19

Figure 6. Fisher 785C Single-Acting and Double-Acting Spring Return Piston Actuator with Handwheel (see tables 14, 15, 17, 18, and 19)

FRONT VIEW

W

SECTION D-D

Z

A4

A

A3

G

AR

B1

�B

A1

TOP VIEW

DD

C C1

GH10539

Figure 7. Fisher 785C Single-Acting and Double-Acting Spring Return Piston Actuator with Hand Pump (see tables 14, 15, 17, 18, and 19)

FRONT VIEW

W

SECTION D-D

Z

A4

A

A3

G

AR

B1

B

A1

TOP VIEW

D

D C

C1

GH10541

D

C1



20

Table 16. 785C Single-Acting and Double-Acting Spring Return (Spring Extends) Dimensions A, A2, A3, B, C, and G(1)

ACTUATORSIZE

YOKEBOSS,Inch

MAX TRAVEL A A2 A3 G(2) B C


335 5 or 5H102 4 1361 53.6 619 24.4 248 9.8 680.5 26.8 1361 53.6 619 24.4

203 8 1600 63.0 671 26.4 349 13.7 800 31.5 1600 63.0 671 26.4

385

5 or 5H

102 4 1351 53.2 609 24.0 248 9.8 675.5 26.6 1351 53.2 609 24.0

203 8 1604 63.1 675 26.6 349 13.7 802 31.6 1604 63.1 675 26.6

318 12 2281 89.8 1110 43.7 451 17.8 1141 44.9 519 20.4 519 20.4

7

102 4 1383 54.4 609 24.0 248 9.8 691.5 27.2 1383 54.4 609 24.0

203 8 1680 66.1 675 26.6 349 13.7 840 33.1 1680 66.1 675 26.6

318 12 2281 89.8 1110 43.7 451 17.8 1141 44.9 519 20.4 519 20.4

435

5 or 5H

102 4 1268 49.9 526 20.7 248 9.8 634 25.0 1268 49.9 526 20.7

203 8 1668 65.7 739 29.1 349 13.7 834 32.8 1668 65.7 739 29.1

318 12 2206 86.9 1035 40.7 451 17.8 1103 43.4 572 22.5 572 22.5

420 16 2507 98.7 1132 44.6 553 21.8 1254 49.4 572 22.5 572 22.5

7

102 4 1300 51.2 526 20.7 248 9.8 650 25.6 1300 51.2 526 20.7

203 8 1744 68.7 739 29.1 349 13.7 872 34.3 1744 68.7 739 29.1

318 12 2206 86.9 1035 40.7 451 17.8 1103 43.4 572 22.5 572 22.5

420 16 2507 98.7 1132 44.6 553 21.8 1254 49.4 572 22.5 572 22.5

485

5 or 5H

102 4 1311 51.6 521 20.5 276 10.9 656 25.8 1311 51.6 521 20.5

203 8 1697 66.8 720 28.3 377 14.8 849 33.4 1697 66.8 720 28.3

318 12 2254 88.7 1035 40.7 479 18.9 1127 44.4 636 25.0 636 25.0

420 16 2555 100.6 1132 44.6 581 22.9 1278 50.3 636 25.0 636 25.0

7

102 4 1343 52.9 521 20.5 276 10.9 672 26.4 1343 52.9 521 20.5

203 8 1773 69.8 720 28.3 377 14.8 887 34.9 1773 69.8 720 28.3

318 12 2254 88.7 1035 40.7 479 18.9 1127 44.4 636 25.0 636 25.0

420 16 2555 100.6 1132 44.6 581 22.9 1278 50.3 636 25.0 636 25.0

535

5 or 5H

102 4 1398 55.0 606 23.9 278 10.9 699 27.5 1398 55.0 606 23.9

203 8 1772 69.8 793 31.2 379 14.9 886 34.9 1772 69.8 793 31.2

318 12 2223 87.5 1002 39.4 481 18.9 1112 43.8 684 26.9 694 27.3

420 16 2476 97.5 1051 41.4 583 23.0 1238 48.7 684 26.9 694 27.3

7

102 4 1430 56.3 606 23.9 278 10.9 715 28.1 1430 56.3 606 23.9

203 8 1848 72.8 793 31.2 379 14.9 924 36.4 1848 72.8 793 31.2

318 12 2223 87.5 1002 39.4 481 18.9 1112 43.8 684 26.9 694 27.3

420 16 1238 48.7 1051 41.4 583 23.0 1238 48.7 684 26.9 694 27.3

585

5H

102 4 1435 56.5 602 23.7 296 11.7 718 28.2 1435 56.5 602 23.7

203 8 1782 70.2 762 30.0 397 15.6 891 35.1 1782 70.2 762 30.0

318 12 2284 89.9 1022 40.2 499 19.6 1142 45.0 499 19.6 750 29.5

420 16 2555 100.6 1089 42.9 601 23.7 1278 50.3 601 23.7 750 29.5

7

102 4 1464 57.6 602 23.7 296 11.7 732 28.8 1464 57.6 602 23.7

203 8 1855 73.0 762 30.0 397 15.6 928 36.5 1855 73.0 762 30.0

318 12 2281 89.8 1022 40.2 499 19.6 1141 44.9 499 19.6 750 29.5

420 16 2551 100.4 1089 42.9 601 23.7 1276 50.2 601 23.7 750 29.5‐continued‐



21

Table 16. 785C Single-Acting and Double-Acting Spring Return (Spring Extends) Dimensions A, A2, A3, B, C, and G(1) (cont.)

ACTUATORSIZE

YOKEBOSS,Inch

MAX TRAVEL A A2 A3 G(2) B C


635

5H

102 4 1473 58.0 640 25.2 296 11.7 737 29.0 1473 58.0 640 25.2

203 8 1742 68.6 722 28.4 397 15.6 871 34.3 1742 68.6 722 28.4

318 12 2264 89.1 992 39.1 499 19.6 1132 44.6 779 30.7 799 31.5

420 16 2458 96.8 1002 39.4 601 23.7 1229 48.4 779 30.7 799 31.5

7

102 4 1502 59.1 640 25.2 296 11.7 751 29.6 1502 59.1 640 25.2

203 8 1903 74.9 810 31.9 397 15.6 952 37.5 1903 74.9 810 31.9

318 12 2261 89.0 992 39.1 499 19.6 1131 44.5 779 30.7 799 31.5

420 16 2454 96.6 1002 39.4 601 23.7 1227 48.3 779 30.7 799 31.5

685

5H

102 4 1622 63.9 754 29.7 306 12.0 811 31.9 1622 63.9 754 29.7

203 8 1840 72.4 785 30.9 407 16.0 920 36.2 1840 72.4 785 30.9

420 16 2493 98.1 992 39.1 611 24.1 1247 49.1 832 32.8 855 33.7

7

102 4 1651 65.0 754 29.7 306 12.0 826 32.5 1651 65.0 754 29.7

203 8 1913 75.3 785 30.9 407 16.0 957 37.7 1913 75.3 785 30.9

420 16 2489 98.0 992 39.1 611 24.1 1245 49.0 832 32.8 855 33.7


Table 17. 785C Single-Acting and Double-Acting Spring Return (Spring Extends) with Manual Override Dimensions A, A1, A2, A3, and A4(1)

ACTUATORSIZE

YOKEBOSS,Inch

MANUALOVERDRIVE

MAX TRAVEL A A1 A2 A3 A4


280 5 or 5H

Hand Wheel

102 4 1450 57.1 438 17.2 610 24.0 296 11.7 290 11.4

203 8 1959.4 77.1 524 20.6 923 36.3 397 15.6 391 15.4

335 5 or 5H102 4 1506 59.3 438 17.2 619 24.4 302.5 11.9 290 11.4

203 8 1757 69.2 524 20.6 671 26.4 403.5 15.9 391 15.4

385

5 or 5H

102 4 1491.5 58.7 438 17.2 609 24.0 285 11.2 290 11.4

203 8 1650.6 65.0 524 20.6 568 22.4 386 15.2 391 15.4

318 12 2448 96.4 664 26.1 1110 43.7 488 19.2 492 19.4

7

102 4 1523.5 58.8 470 18.5 609 24.0 285 11.2 290 11.4

203 8 1726.6 73.0 600 23.6 568 22.4 386 15.2 391 15.4

318 12 2448 60.1 664 26.1 1110 43.7 488 19.2 492 19.4

435

5 or 5H

Hand Pump

102 4 1493.7 58.8 438 17.2 526 20.7 282 11.1 375 14.8

203 8 1853.8 73.0 524 20.6 680 26.8 383 15.1 496 19.5

318 12 2470 97.2 664 26.1 1035 40.7 516 20.3 597 23.5

420 16 2790 109.8 766 30.2 1132 44.6 618 24.3 698 27.5

7

102 4 1525.7 60.1 470 18.5 526 20.7 282 11.1 375 14.8

203 8 1929.8 76.0 600 23.6 680 26.8 383 15.1 496 19.5

318 12 2470 97.2 664 26.1 1035 40.7 516 20.3 597 23.5

420 16 2790 109.8 766 30.2 1132 44.6 618 24.3 698 27.5

485

5 or 5H

102 4 1632.2 64.3 438 17.2 521 20.5 313 12.3 375 14.8

203 8 1986.6 78.2 524 20.6 665 26.2 414 16.3 496 19.5

318 12 2622 103.2 664 26.1 1035 40.7 516 20.3 597 23.5

420 16 2947 116.0 766 30.2 1132 44.6 618 24.3 698 27.5

7

102 4 1664.2 65.5 470 18.5 521 20.5 313 12.3 375 14.8

203 8 2062.6 81.2 600 23.6 665 26.2 414 16.3 496 19.5

318 12 2622 103.2 664 26.1 1035 40.7 516 20.3 597 23.5

420 16 2940 115.7 766 30.2 1132 44.6 618 24.3 698 27.5‐continued‐



22

Table 17. 785C Single-Acting and Double-Acting Spring Return (Spring Extends) with Manual Override Dimensions A, A1, A2, A3, and A4(1) (cont.)

ACTUATORSIZE

YOKEBOSS,Inch

MANUALOVERDRIVE

MAX TRAVEL A A1 A2 A3 A4


535

5 or 5H

Hand Pump

102 4 1774.9 69.9 438 17.2 606 23.9 317 12.5 375 14.8

203 8 2123.7 83.6 524 20.6 742 29.2 418 16.5 496 19.5

318 12 2652 104.4 766 30.2 1002 39.4 622 24.5 698 27.5

420 16 2931 115.4 664 26.1 1051 41.4 520 20.5 597 23.5

7

102 4 1806.9 71.1 470 18.5 606 23.9 317 12.5 375 14.8

203 8 2199.7 86.6 600 23.6 742 29.2 418 16.5 496 19.5

318 12 2652 104.4 664 26.1 1002 39.4 622 24.5 698 27.5

420 16 2931 115.4 766 30.2 1051 41.4 520 20.5 597 23.5

585

5H

102 4 1917 75.5 438 17.2 602 23.7 348 13.7 392 15.4

203 8 2231.6 87.9 524 20.6 699 27.5 449 17.7 513 20.2

318 12 2827 111.3 687 27.0 1002 39.4 551 21.7 614 24.2

420 16 3129 123.2 789 31.1 1089 42.9 653 25.7 715 28.1

7

102 4 1946 76.6 470 18.5 602 23.7 348 13.7 392 15.4

203 8 2304.6 90.7 600 23.6 699 27.5 449 17.7 513 20.2

318 12 2824 111.2 684 26.9 1002 39.4 551 21.7 614 24.2

420 16 3125 123.0 785 30.9 1089 42.9 653 25.7 715 28.1

635

5H

102 4 2033 80.0 438 17.2 640 25.2 349 13.7 392 15.4

203 8 2426.8 95.5 524 20.6 810 31.9 450 17.7 513 20.2

318 12 2896 114.0 687 27.0 1002 26.9 552 21.7 614 24.2

420 16 3129 123.2 789 31.1 992 30.9 664 26.1 715 28.1

7

102 4 2062 81.2 470 18.5 640 25.2 349 13.7 392 15.4

203 8 2499.8 98.4 600 23.6 810 31.9 450 17.7 513 20.2

318 12 2893 113.9 684 26.9 810 31.9 450 17.7 513 20.2

420 16 3125 123.0 785 30.9 1002 32.0 552 21.7 614 24.2

685

5H

102 4 2348 92.4 486 19.1 754 29.7 373 14.7 392 15.4

203 8 2605.7 102.6 572 22.5 785 30.9 474 18.7 513 20.2

318 12 3104 122.2 712 28.0 1002 39.4 576 22.7 614 24.2

420 16 3338 131.4 814 32.0 992 39.1 678 26.7 715 28.1

7

102 4 2377 93.6 515 20.3 754 29.7 373 14.7 392 15.4

203 8 2678.7 105.5 645 25.4 785 30.9 474 18.7 513 20.2

318 12 3101 122.1 709 27.9 1002 39.4 576 22.7 614 24.2

420 16 3334 131.3 810 31.9 992 39.1 678 26.7 715 28.1

1. Dimensions are maximum

Table 18. 785C Single-Acting and Double-Acting Spring Return (Spring Extends) with Manual Override Dimensions B, B1, C, C1, and G(1)

ACTUATORSIZE

YOKEBOSS,Inch

MANUALOVERDRIVE

MAX TRAVEL G(2) B B1 C C1


280 5 or 5H

Hand Wheel

102 4 725 28.5 850 33.5 419 16.5 464 18.3 - - - - - -

203 8 979.7 38.6 850 33.5 419 16.5 464 18.3 - - - - - --

335 5 or 5H102 4 752.9 29.6 1250 49.2 472 18.6 517 20.4 - - - - - -

203 8 878.25 34.6 1250 49.2 472 18.6 517 20.4 - - - - - -

385

5 or 5H

102 4 745.75 29.4 1400 55.1 519 20.4 564 22.2 - - - - - -

203 8 825.3 32.5 1400 55.1 519 20.4 564 22.2 - - - - - -

318 12 1224 48.2 1400 55.1 519 20.4 564 22.2 - - - - - -

7

102 4 761.75 30.0 1400 55.1 519 20.4 564 22.2 - - - - - -

203 8 863.3 34.0 1400 55.1 519 20.4 564 22.2 - - - - - -

318 12 1224 48.2 1400 55.1 519 20.4 564 22.2 - - - - - -‐continued‐



23

Table 18. 785C Single-Acting and Double-Acting Spring Return (Spring Extends) with Manual Override Dimensions B, B1, C, C1, and G(1) (cont.)

ACTUATORSIZE

YOKEBOSS,Inch

MANUALOVERDRIVE

MAX TRAVEL G(2) B B1 C C1


435

5 or 5H

Hand Pump

102 4 746.85 29.4 908 35.7 572 22.5 846 33.3 565 22.2

203 8 926.9 36.5 908 35.7 572 22.5 846 33.3 565 22.2

318 12 1235 48.6 908 35.7 572 22.5 846 33.3 565 22.2

420 16 1395 54.9 908 35.7 572 22.5 846 33.3 565 22.2

7

102 4 762.9 30.0 908 35.7 572 22.5 846 33.3 565 22.2

203 8 964.9 38.0 908 35.7 572 22.5 846 33.3 565 22.2

318 12 1235 48.6 908 35.7 572 22.5 858 33.8 630 24.8

420 16 1395 54.9 908 35.7 572 22.5 858 33.8 630 24.8

485

5 or 5H

102 4 816.1 32.1 940 37.0 636 25.0 858 33.8 630 24.8

203 8 993.3 39.1 940 37.0 636 25.0 858 33.8 630 24.8

318 12 1311 51.6 940 37.0 636 25.0 858 33.8 630 24.8

420 16 1470 57.9 940 37.0 636 25.0 858 33.8 630 24.8

7

102 4 832.1 32.8 940 37.0 636 25.0 858 33.8 630 24.8

203 8 1031.3 40.6 940 37.0 636 25.0 858 33.8 630 24.8

318 12 1311 51.6 940 37.0 636 25.0 858 33.8 630 24.8

420 16 1470 57.9 940 37.0 636 25.0 858 33.8 630 24.8

535

5 or 5H

102 4 887.45 34.9 962 37.9 684 26.9 915 36.0 680 26.8

203 8 1061.85 41.8 962 37.9 684 26.9 915 36.0 680 26.8

318 12 1326 52.2 962 37.9 684 26.9 915 36.0 680 26.8

420 16 1465 57.7 962 37.9 684 26.9 915 36.0 680 26.8

7

102 4 903.45 35.6 962 37.9 684 26.9 915 36.0 680 26.8

203 8 1099.85 43.3 962 37.9 684 26.9 915 36.0 680 26.8

318 12 1326 52.2 962 37.9 684 26.9 915 36.0 680 26.8

420 16 1465 57.7 962 37.9 684 26.9 915 36.0 680 26.8

585

5H

102 4 958.5 37.7 1102 43.4 737 29.0 983 38.7 730 28.7

203 8 1115.8 43.9 1102 43.4 737 29.0 983 38.7 730 28.7

318 12 1414 55.7 1102 43.4 737 29.0 983 38.7 730 28.7

420 16 1565 61.6 1102 43.4 737 29.0 983 38.7 730 28.7

7

102 4 973 38.3 1102 43.4 737 29.0 983 38.7 730 28.7

203 8 1152.3 45.4 1102 43.4 737 29.0 983 38.7 730 28.7

318 12 1412 55.6 1102 43.4 737 29.0 983 38.7 730 28.7

420 16 1563 61.5 1102 43.4 737 29.0 983 38.7 730 28.7

635

5H

102 4 1016.5 40.0 1127 44.4 779 30.7 1007 39.6 785 30.9

203 8 1213.4 47.8 1127 44.4 779 30.7 1007 39.6 785 30.9

318 12 1448 57.0 1127 44.4 779 30.7 1007 39.6 785 30.9

420 16 1564 61.6 1127 44.4 779 30.7 1007 39.6 785 30.9

7

102 4 1031 40.6 1127 44.4 779 30.7 1007 39.6 785 30.9

203 8 1249.9 49.2 1127 44.4 779 30.7 1007 39.6 785 30.9

318 12 1447 57.0 1127 44.4 779 30.7 1007 39.6 785 30.9

420 16 1562 61.5 1127 44.4 779 30.7 1007 39.6 785 30.9

685

5H

102 4 1174 46.2 1153 45.4 832 32.8 1035 40.7 840 33.1

203 8 1302.85 51.3 1153 45.4 832 32.8 1035 40.7 840 33.1

318 12 1552 61.1 1153 45.4 832 32.8 1035 40.7 840 33.1

420 16 1669 65.7 1153 45.4 832 32.8 1035 40.7 840 33.1

7

102 4 1188.5 46.8 1153 45.4 832 32.8 1035 40.7 840 33.1

203 8 1339.35 52.7 1153 45.4 832 32.8 1035 40.7 840 33.1

318 12 1551 61.1 1153 45.4 832 32.8 1035 40.7 840 33.1

420 16 1667 65.6 1153 45.4 832 32.8 1035 40.7 840 33.1




24

Table 19. 785C Single-Acting Spring Return (Spring Retracts or Spring Extends) Dimensions Z and W

ACTUATOR SIZE

WITHOUT MANUAL OVERRIDE WITH MANUAL OVERRIDE

Z W Z W

5, 5H, or 7 Inch Yoke Boss 5, 5H, or 7 Inch Yoke Boss

mm Inch mm Inch mm Inch mm Inch

335 254 10 292 11.5 254 10 292 11.5

385 330 13 330 13 330 13 330 13

435 330 13 330 13 330 13 330 13

485 330 13 330 13 330 13 330 13

535 330 13 330 13 330 13 330 13

585 487 19.2 436 17.2 487 19.2 436 17.2

635 487 19.2 436 17.2 487 19.2 436 17.2

685 487 19.2 436 17.2 487 19.2 436 17.2

Table 20. 785C Double-Acting Springless Approximate Weights for Constructions without Manual OverrideActuator Size 280, 335, 385, and 435

MAXIMUMVALVE

TRAVEL,mm

(inches)

APPROXIMATE WEIGHT FOR ACTUATOR SIZE, kg (lbs)

280 335 385 435

5 YokeBoss

5H YokeBoss

5 YokeBoss

5H YokeBoss

5 YokeBoss

5H YokeBoss

7 YokeBoss

5 YokeBoss

5H YokeBoss

7 YokeBoss

102 (4) 126 (277) 126 (277) 157 (345) 158 (345) 205 (451) 203 (451) 203 (449) 238 (524) 238 (524) 237 (522)

203 (8) 137 (302) 137 (302) 171 (375) 171 (375) 221 (488) 222 (490) 222 (490) 257 (566) 256 (565) 258 (568)

318 (12) 151 (333) 151 (333) 187 (411) 187 (411) 240 (530) 240 (530) 237 (523) 278 (613) 278 (613) 275 (606)

420 (16) 163 (360) 163 (360) 201 (443) 201 (443) 258 (568) 258 (568) 255 (561) 298 (657) 298 (657) 295 (650)

521 (20) 175 (386) 175 (386) 216 (475) 216 (475) 275 (606) 275 (606) 272 (600) 317 (700) 317 (700) 314 (693)

623 (24) 188 (413) 188 (413) 230 (507) 230 (507) 292 (644) 292 (644) 289 (637) 337 (742) 337 (742) 334 (736)

Table 21. 785C Double-Acting Springless Approximate Weights for Constructions without Manual OverrideActuator Size 485, 535, 585, 635, and 685

MAXIMUMVALVE

TRAVEL,mm

(inches)


485 535 585 635 685

5 YokeBoss

5H YokeBoss

7 YokeBoss

5 YokeBoss

5H YokeBoss

7 YokeBoss

5H YokeBoss

7 YokeBoss

5H YokeBoss

7 YokeBoss

5H YokeBoss

7 YokeBoss

102(4)

327(720)

326(720)

325(717)

382(842)

382(842)

381(839)

513(1130)

512(1128)

590(1300)

589(1298)

697(1536)

696(1534)

203(8)

348(766)

347(766)

345(769)

405(894)

405(893)

406(896)

541(1193)

543(1198)

624(1376)

627(1381)

733(1615)

735(1621)

318(12)

371(819)

371(819)

368(812)

431(951)

431(951)

428(944)

573(1263)

570(1257)

662(1460)

659(1454)

772(1703)

769(1696)

420(16)

393(867)

393(867)

390(860)

456(1005)

456(1005)

453(998)

602(1328)

599(1321)

698(1539)

695(1532)

809(1784)

806(1777)

521(20)

415(915)

415(915)

412(908)

480(1058)

480(1058)

477(1051)

632(1393)

629(1386)

734(1617)

731(1611)

846(1866)

843(1859)

623(24)

437(963)

437(963)

433(956)

504(1111)

504(1111)

501(1104)

661(1458)

658(1451)

769(1696)

766(1689)

883(1947)

880(1940)



25

Table 22. 785C Double Acting Springless Approximate Weights for Constructions with Manual OverrideActuator Size 280, 335, 385, and 435MAXIMUM

VALVETRAVEL,

mm(inches)


280 335 385 435

5 YokeBoss

5H YokeBoss

5 YokeBoss

5H YokeBoss

5 YokeBoss

5H YokeBoss

7 YokeBoss

5 YokeBoss

5H YokeBoss

7 YokeBoss

102 (4) 152 (336) 152 (336) 193 (425) 193 (425) 224 (494) 224 (494) 223 (491) 313 (689) 312 (689) 311 (686)

203 (8) 166 (366) 166 (366) 209 (460) 209 (460) 243 (536) 243 (535) 244 (538) 337 (744) 337 (743) 338 (746)

318 (12) 182 (403) 182 (403) 230 (507) 230 (507) 265 (584) 265 (584) 262 (577) 365 (804) 365 (804) 362 (798)

420 (16) 197 (435) 197 (435) 249 (549) 249 (549) 284 (627) 284 (627) 281 (620) 391 (862) 391 (862) 388 (855)

521 (20) 211 (467) 211 (467) 268 (591) 268 (591) 304 (670) 304 (670) 301 (664) 416 (917) 416 (917) 413 (911)

623 (24) 226 (499) 226 (499) 287 (633) 287 (633) 324 (714) 324 (714) 321 (707) 442 (974) 442 (974) 439 (967)

Table 23. 785C Double-Acting Springless Approximate Weights for Constructions with Manual OverrideActuator Size 485, 535, 585, 635, and 685MAXIMUM

VALVETRAVEL,

mm(inches)


485 535 585 635 685

5 YokeBoss

5H YokeBoss

7 YokeBoss

5 YokeBoss

5H YokeBoss

7 YokeBoss

5H YokeBoss

7 YokeBoss

5H YokeBoss

7 YokeBoss

5H YokeBoss

7 YokeBoss

102(4)

425(938)

425(937)

424(935)

481(1060)

481(1059)

479(1057)

624(1375)

623(1373)

701(1543)

700(1543)

855(1884)

854(1882)

203(8)

454(1002)

454(1001)

455(1004)

512(1129)

512(1129)

513(1132)

663(1462)

665(1467)

746(1650)

749(1650)

903(1990)

905(1996)

318(12)

486(1072)

486(1072)

483(1066)

547(1205)

547(1205)

544(1199)

706(1557)

703(1550)

794(1750)

791(1744)

955(2105)

952(2099)

420(16)

516(1139)

516(1139)

514(1132)

579(1277)

579(1277)

576(1270)

747(1646)

743(1639)

842(1857)

839(1850)

1004(2214)

1001(2207)

521(20)

546(1205)

546(1205)

544(1199)

612(1348)

612(1348)

609(1342)

787(1735)

784(1728)

889(1959)

886(1953)

1054(2323)

1051(2316)

623(24)

577(1271)

577(1271)

574(1265)

644(1420)

644(1420)

641(1413)

827(1824)

824(1817)

935(2062)

932(2055)

1103(2432)

1100(2425)

Table 24. 785C Double-Acting and Single-Acting Spring Return Approximate Weights for Constructions without Manual Override Actuator Size 280, 335, 385, and 435

MAXIMUMVALVE

TRAVEL,mm

(inches)


280 335 385 435

5 YokeBoss

5H YokeBoss

5 YokeBoss

5H YokeBoss

5 YokeBoss

5H YokeBoss

7 YokeBoss

5 YokeBoss

5H YokeBoss

7 YokeBoss

102 (4) 195 (431) 195 (430) 217 (478) 216 (477) 301 (704) 301 (704) 299 (701) 394 (869) 394 (734) 393 (866)

203 (8) 242 (533) 241 (532) 285 (628) 284 (627) 292 (685) 292 (684) 291 (682) 333 (735) 333 (643) 332 (732)

318 (12) - - - - - - - - - - - - 452 (998) 452 (998) 449 (991) 411 (1059) 411 (1059) 408 (1052)

420 (16) - - - - - - - - - - - - - - - - - - - - - 527 (1162) 527 (1162) 524 (1155)



26

Table 25. 785C Double-Acting and Single-Acting Spring Return Approximate Weights for Constructions without Manual Override Actuator Size 485, 535, 585, 635, and 685

MAXVALVE

TRAVEL,mm

(inches)


485 535 585 635 685

5 YokeBoss

5H YokeBoss

7 YokeBoss

5 YokeBoss

5H YokeBoss

7 YokeBoss

5H YokeBoss

7 YokeBoss

5H YokeBoss

7 YokeBoss

5H YokeBoss

7 YokeBoss

102(4)

496(1093)

495(1092)

494(1090)

646(1424)

646(1424)

645(1421)

794(1750)

793(1748)

872(1921)

871(1920)

957(2110)

957(2109)

203(8)

483(1064)

483(1064)

481(1061)

548(1209)

548(1209)

547(1206)

788(1737)

787(1735)

864(1905)

863(1903)

979(2158)

978(2156)

318(12)

574(1265)

574(1265)

571(1258)

888(1958)

888(1958)

885(1951)

949(2091)

945(2084)

1045(2303)

1042(2296)

1155(2547)

1152(2540)

420(16)

623(1373)

623(1373)

620(1366)

919(2028)

919(2028)

917(2021)

996(2196)

993(2189)

1172(2584)

1169(2577)

1284(2831)

1281(2824)

Table 26. 785C Double-Acting and Single-Acting Spring Return Approximate Weights for Constructions with Manual Override Actuator Size 280, 335, 385, and 435

MAXIMUMVALVE

TRAVEL,mm (inches)


280 335 385 435

5 YokeBoss

5H YokeBoss

5 YokeBoss

5H YokeBoss

5 YokeBoss

5H YokeBoss

7 YokeBoss

5 YokeBoss

5H YokeBoss

7 YokeBoss

102 (4) 222 (488) 221 (488) 252 (556) 252 (555) 319 (704) 319 (704) 318 (701) 468 (1032) 468 (1031) 467 (1029)

203 (8) 270 (596) 270 (596) 320 (706) 320 (705) 311 (685) 310 (684) 309 (682) 407 (898) 407 (897) 406 (895)

318 (12) - - - - - - - - - - - - 476 (1049) 476 (1049) 473 (1042) 497 (1248) 497 (1248) 494 (1242)

420 (16) - - - - - - - - - - - - - - - - - - - - - 619 (1365) 619 (1365) 616 (1359)

Table 27. 785C Double-Acting and Single-Acting Spring Return Approximate Weights for Constructions with Manual Override Actuator Size 485, 535, 585, 635, and 685MAXIMUM

VALVETRAVEL,

mm(inches)


485 535 585 635 685

5 YokeBoss

5H YokeBoss

7 YokeBoss

5 YokeBoss

5H YokeBoss

7 YokeBoss

5H YokeBoss

7 YokeBoss

5H YokeBoss

7 YokeBoss

5H YokeBoss

7 YokeBoss

102(4)

594(1309)

593(1308)

592(1306)

744(1640)

744(1640)

743(1637)

898(1992)

903(1990)

981(2163)

980(2161)

1114(2455)

1113(2454)

203(8)

581(1280)

580(1280)

579(1277)

646(1425)

646(1424)

645(1422)

541(1979)

897(1977)

973(2146)

973(2144)

1135(2502)

1134(2501)

318(12)

688(1517)

688(1517)

685(1510)

1001(2208)

1001(2208)

999(2201)

1080(2381)

1077(2374)

1175(2589)

1171(2583)

1336(2946)

1333(2939)

420(16)

745(1641)

745(1641)

742(1635)

1041(2295)

1041(2295)

1039(2289)

1139(2511)

1136(2504)

1315(2899)

1312(2892)

1478(3258)

1475(3251)



27

Table 28. Lifting Point Load Ratings

ACTUATOR SIZE LIFTING ORIENTATIONNUMBER OF LIFTING

POINTS USED

MAXIMUM WELDED EYELET LOAD

AT LIFTING ANGLE ��20�(SEE FIGURE 5)

Kg lbs

280

Actuator Centerline Horizontal(1)

2 1747 3851

335 2 1747 3851

385 2 1747 3851

435 2 1747 3851

485 2 6330 13955

535 2 6330 13955

585 2 6330 13955

635 2 6330 13955

685 2 6330 13955

ACTUATOR SIZE LIFTING ORIENTATIONNUMBER OF LIFTING

POINTS USED

MAXIMUM LOAD AT EYEBOLT

LIFTING ANGLE ��45�(SEE FIGURE 6)

Kg lbs

280

Actuator Centerline Vertical(2)

4 864 1905

335 4 864 1905

385 4 864 1905

435 4 864 1905

485 4 3096 6826

535 4 3096 6826

585 4 3096 6826

635 4 3096 6826

685 4 3096 6826

1. Welded eyelets for horizontal lifting are only available for the 785C Spring Return.2. Vertical lifting loads are applicable to both the 785C Springless and Spring Return.

Figure 8. Lifting Angle for Welded Eyelets

V

�

N



28

Figure 9. Spring Return Actuator Centerline Horizontal Lift

� �

NN

Figure 10. Spring Return Actuator Centerline Vertical Lift

��

N

InstallationKey numbers in this procedure are shown in figures 16 to 34, unless otherwise indicated.

WARNING

To avoid personal injury or property damage caused by cylinder fracture as a result of piston impact, install the stemconnector securely before supplying pressure to the positioner. Use only a regulator-controlled air supply to move theactuator piston so that you can install the stem connector. Do not use the positioner to move the actuator piston beforeinstalling the stem connector.

Always wear protective gloves, clothing, and eyewear when performing any installation operations to avoid personalinjury.

If installing into an existing application, also refer to the warning at the beginning of the Maintenance section in thismanual.

Check with your process or safety engineer for any additional measures that must be taken to protect against processmedia.

To avoid personal injury or property damage caused by bursting of pressure‐retaining parts, be certain the cylinderpressure or other pressure ratings do not exceed the limits listed in table 1. Use pressure‐limiting or pressure‐relievingdevices to prevent cylinder pressure or other pressures from exceeding these limits.

To avoid personal injury or equipment damage, use proper lifting and rigging practices while lifting the actuator orvalve/actuator assembly. For all mounting procedures use an adequately sized chain, sling, hoist, or crane to handle theactuator and any attached accessories and/or valve. Use caution during lifting and handling to prevent slippage, swinging,faulty equipment connections, or sudden shock loads.



29

CAUTION

Special care must be taken when installing an actuator in a horizontal service orientation. To avoid cantilever loads on thevalve stem and yoke, it is the customer’s responsibility to ensure proper support for a horizontal actuator.

When an actuator and control valve are shipped together as a control valve assembly, the actuator is normallymounted on the valve. Follow the valve instructions when installing the valve in the pipeline. If the actuator is shippedseparately or if it is necessary to mount the actuator on the valve, perform the actuator mounting procedures in thisinstruction manual. Refer to the individual product instruction manuals for the installation or mounting of a FIELDVUEDVC6200 digital valve controller.

If the actuator is being installed without a positioner, the cylinder loading pressures should be supplied through a4-way solenoid valve or a switching valve.

Pressure connections are located on top of the pneumatic cylinder end flange (key 2210) and on the side of thepneumatic cylinder head flange (key 2201).

� The supply pressure medium should be clean, dry filtered air. If the supply source is capable of exceeding themaximum actuator operating pressure or positioner supply pressure, appropriate steps must be taken duringinstallation to protect the positioner and all connected equipment against over pressurization.

� The control valve should be located where it will be accessible for servicing. Space should be left above and belowthe control valve to permit removal of the actuator and valve plug.

Actuator Earth GroundingAll Fisher 785C series actuators are provided with a threaded actuator earth grounding interface on the yoke (spool)for the earth connection as shown in the figure 11.

CAUTION

Proper connection to the earth grounding interface is required for compliance with ATEX regulations.



30

Figure 11. Actuator Earth Grounding Interface

ACTUATOR EARTHGROUND INTERFACE

Three‐Way Valve Applications NoteIn three-way valve applications where the actuator fully strokes at a frequency of once per minute or faster, and thestroking speed is rapid (less than 0.5 seconds per stroke), there is a possibility that the stem can fracture at the plug ifthe actuator cylinder pressure is greater than 5.5 bar (80 psig). This can cause loss of control of process fluid andfurther damage to the actuator. Considerations should be given to the use of high-strength, fatigue-resistant stemmaterials in these applications.

WARNING

To avoid loss of control of process fluid and subsequent personal injury or property damage caused by bursting ofpressure‐retaining parts, be sure the cylinder pressure does not exceed 5.5 bar (80 psig) in high cycle‐rate, fast strokingspeed, three‐way valve applications.

Manual OverrideThe actuator can be equipped with a manual override. The manual override can be executed with a Manual Handwheelor a Manual Hydraulic Pump which can operate the actuator.

Manual Handwheel OperationIf manual operation is required for actuator sizes 280, 335, and 385 a manual handwheel should be equipped asstandard construction.

CAUTION

To avoid damage to actuator parts and difficult operation of actuator handwheels, open the bypass valve before using ahandwheel. Do not disengage the handwheel if the spring thrust is not balanced by pneumatic load for spring returnactuator.



31

A bypass assembly is furnished only when an actuator with manual override is specified. The bypass assembly allowsthe pressure to equalize on either side of the actuator piston, so that the manual override can be used to position thecontrol valve. Flow through the bypass tubing is controlled by an angle needle valve, which is operated manually. Thisvalve should be closed when air pressure is being used to operate the actuator.

The following steps reference figure 12. Refer to table 6 for handwheel specifications.

1. Engage the manual override by rotating its handle, reference figure 12. Note that there is only one position (at 360°rotation of the handwheel) where the handle will correctly engage the manual operation. To reach that positionduring the rotation of the handle, slowly rotate the handwheel until the correct position, as indicated on thewarning plate shown in figure 12.

2. Turn the handwheel of the manual override clockwise to close, or counter clockwise to open, as indicated on theinstruction label.

3. Check the correct operation of the actuator by monitoring the movement of the travel indicator.

4. Once manual operation is completed, the bypass valve should be close and remain shut off during pneumaticsupply air operation.

5. Ensure the unbalanced thrust, such as spring return actuator spring thrust, is balanced by applying a pneumaticload and disengage the manual handwheel by rotating the handle as shown on the instruction plate. This allows theactuator to be operated by the pneumatic supply.

If it is necessary to keep the valve in its position and if the pneumatic supply is not restored yet, do not disengagethe handwheel.

For spring return actuator, if it is not necessary to keep the valve in its position and if the pneumatic supply is notrestored yet, in order to disengage the handwheel, turn the handwheel to the end which spring would fully releasewithout applying any thrust to the handwheel, to get an easy disengagement of the handwheel.

Figure 12. Top Mounted Manual Handwheel

HANDLE

HANDWHEEL

INSTRUCTION

WARNING



32

Figure 13. Top Mounted Manual Handwheel Engagement/Disengagement Instruction Label

ENGAGED

DISENGAGED

TO OPEN

TO CLOSE

Manual Hydraulic Handpump OperationIf manual operation is required, actuator sizes 435, 485, 535, 585, 635, and 685 should be equipped with a manualhandpump as standard construction.

CAUTION

The manual handpump control unit must be installed in vertical up direction per figure 8. For application requiring actuatorhorizontal installation, a special design handpump support and hydraulic tubing must be used to install handpump invertical up direction. Please contact your Emerson sales office for further information of manual handpump for actuatorhorizontal installation.



33

Figure 14. Handpump Control Unit

NOTE:

HANDPUMP CONTROL UNIT MUST BE INSTALLED IN VERTICAL 'UP' DIRECTION.11

1 1

A bypass assembly is furnished only when an actuator with manual override is specified. The bypass assembly allowsthe pressure to equalize on either side of the actuator piston, so that the manual override can be used to position thecontrol valve. Flow through the bypass tubing is controlled by an angle needle valve, which is operated manually. Thisvalve should be closed when supply pressure is being used to operate the actuator.

The following steps are referenced in figures 15, 16, and 17. Refer to table 7 for handpump specifications and figures18 through 23 for handpump schematics and more detail instructions.

1. Select “Manual Opening” or “Manual Closing” by rotating the Engagement/Disengagement handle as indicated onthe instruction plate from pneumatic operation “REMOTE” mode.

2. Actuate the handpump according to the figures 18 through 23 handpump schematic detail instructions until thedesired position of the actuator is reached.

3. Check the correct operation of the actuator through the visual travel indicator.

4. Once manual operation is completed, rotate the handle to the “REMOTE” position, as indicated on the instructionplate in figure 15, to disengage the manual operator. Follow the figures 18 through 23 handpump schematic detailinstructions to allow the “REMOTE “operation with the pneumatic supply. Once manual operation is completed, thebypass valve should be close and remain shutoff during pneumatic supply air operation.



34

Figure 15. Manual Hydraulic Handpump Engagement/Disengagement Instructions Plate

Figure 16. Manual Hydraulic Handpump Typical Constructions(Design Varies for Different Actuator Type and Handpump Type)

STOP VALVE FOR FAST STROKE TYPE MHQ

HANDPUMPHANDLE

STOP VALVE(MULTIPLE POSITIONS SHOWING)

ENGAGEMENT ANDDISENGAGEMENTHANDLE



35

Figure 17. Manual Hydraulic Handpump Typical Constructions(Design Varies for Different Actuator Type and Handpump Type)

STOP VALVE FOR FAST STROKE TYPE MHQ

STOP VALVE (MULTIPLE POSITIONS SHOWING)

HANDPUMPHANDLE

Table 29. Handpump Schematics(1)

Actuator Type Handpump Type Schematics Figure

785C Spring Return Rod Extend (Fail Down)

Single or Double Acting

Fast Stroke MHQ 18

Standard Stroke MHP 19

785C Spring Return Rod Extend (Fail Up)

Single or Double Acting

Fast Stroke MHQ 20

Standard Stroke MHP 21

785C Springless, Double ActingStandard Stroke MHP 22

Fast Stroke MHQ 231. Notice the 785C Spring Return schematics drawn as single acting would also work for double acting.



36

Figure 18. Handpump Schematic: Fast Stroke MHQ Handpump for 785C Spring Return Rod Extend (Fail Down), Single or Double Acting

PNEUMATIC SUPPLY

PNEUMATIC REMOTE CONTROL TO OPENPRESSURIZED PERMANENTLY THE PNEUMATIC SUPPLY LINE.

PNEUMATIC REMOTE CONTROL TO CLOSEDE-PRESSURIZED THE PNEUMATIC SUPPLY LINE.

EMERGENCY MANUAL OPERATIONIN CASE OF PNEUMATIC SUPPLY FAILURE, CLOSE THE STOP VALVE 351B,SELECT BY THE VALVE “5-D” THE OPENING OPERATION AND ACTUATETHE HAND PUMP “5-P”.AT THE END OF THE OPENING OPERATION CLOSE THE VALVE 651A.NOTE: THE VALVE “5-D” MUST BE IN “REMOTE CONTROL” POSITIONAND THE STOP VALVES 651A AND 651B MUST BE OPEN TO ALLOW THEOPERATION WITH PNEUMATIC SUPPLY.

1 SINGLE ACTING SPRING RETURN PNEUMATIC LINEAR ACTUATOR3 HYDRAULIC CYLINDER5 MANUAL OVERRIDE

R — RELIEF VALVEP — HAND PUMPD — HAND OPERATED DIRECTIONAL CONTROL VALVE

351 STOP VALVE395 RELIEF VALVE

CLO

SE



37

Figure 19. Handpump Schematic: Standard Stroke MHP Handpump for 785C Spring Return Rod Extend (Fail Down), Single or Double Acting

PNEUMATIC SUPPLY

PNEUMATIC REMOTE CONTROL TO OPENPRESSURIZED PERMANENTLY THE PNEUMATIC SUPPLY LINE.

PNEUMATIC REMOTE CONTROL TO CLOSEDE-PRESSURIZED THE PNEUMATIC SUPPLY LINE.

EMERGENCY MANUAL OPERATIONIN CASE OF PNEUMATIC SUPPLY FAILURE, SELECT BY THE VALVE “5-D”THE OPENING OPERATION AND ACTUATE THE HAND PUMP “5-P”.AT THE END OF THE OPENING OPERATION CLOSE THE VALVE 351.NOTE: THE VALVE “5-D” MUST BE IN “REMOTE CONTROL” POSITIONAND THE STOP VALVES 351 AND MUST BE OPEN TO ALLOW THE OPERATION WITH PNEUMATIC SUPPLY.

1 SINGLE ACTING SPRING RETURN PNEUMATIC LINEAR ACTUATOR3 HYDRAULIC CYLINDER5 MANUAL OVERRIDE

R — RELIEF VALVEP — HAND PUMPD — HAND OPERATED DIRECTIONAL CONTROL VALVE

351 STOP VALVE395 RELIEF VALVE

CLO

SE



38

Figure 20. Handpump Schematic: Fast Stroke MHQ Handpump for 785C Spring Return Rod Retract (Fail Up), Single or Double Acting

PNEUMATIC SUPPLY

PNEUMATIC REMOTE CONTROL TO CLOSEPRESSURIZED PERMANENTLY THE PNEUMATIC SUPPLY LINE.

PNEUMATIC REMOTE CONTROL TO OPENDE-PRESSURIZED THE PNEUMATIC SUPPLY LINE.

EMERGENCY MANUAL OPERATIONIN CASE OF PNEUMATIC SUPPLY FAILURE, CLOSE THE STOP VALVE351B, SELECT BY THE VALVE “5-D” THE CLOSING OPERATION ANDACTUATE THE HA

Documents

Fisher 785C Piston Actuators - Emerson Electric · 2020. 8. 20. · 3 Standard temperature -20 to 100 C (-4 to 212 F) and -40 to 100 C (-40 to 212 F) are PED 2014/68/EU and 2006/42/EC