SECTION 26 36 00-ENCLOSED TRANSFER SWITCHES.pdf

MINISTRY OF HOUSING Western Sector Projects Sitework & Infrastructure OMRANIA and ASSOCIATES Project Specification

ENCLOSED TRANSFER SWITCHES SECTION 26 36 00 - 1

SECTION 26 36 00

ENCLOSED TRANSFER SWITCHES PART 1: GENERAL

1.01 SECTION INCLUDES

A Enclosed transfer switches including, but not limited to the following:

1. Manual transfer switches.

2. Automatic transfer switches.

3. Automatic sequence of operation.

4. Additional features.

5. Microprocessor based controller.

6. Remote annunciation system.

7. Factory testing.

1.02 RELATED SECTIONS

A Section 01 31 00 Project Management and Coordination.

B Section 0133 00 Submittal Procedures.

C Section 01 61 00 Common Product Requirements.

D Section 01 75 00 Starting of Systems.

E Section 01 77 00 Contract Closeouts.

F Section 01 78 23 Operation and Maintenance Data.

G Section 01 78 36 Warranties.

H Section 26 05 00 Common Work Results for Electrical

I Section 26 05 53 Electrical Identification.

J Section 26 05 19 LV Cables and Wires.

K Section 26 05 29 Equipment Connections and Supports.

L Section 26 24 13 LV Power Distribution Boards.

M Section 26 32 13.13 LV Emergency Power Generation System.

N Section 26 05 26 Earthing System.



O Section 26 08 00 Testing and Commissioning of Electrical Systems.

1.03 REFERENCES

A SASO Saudi Arabian Standards Organization.

B IEC 60073 Basic and Safety Principles for Man-Machine Interface, Marking and Identification.

C IEC 60364 Electrical Installations of Buildings.

D IEC 60439 LV Switchgear and Control gear Assemblies.

E IEC 60529 Degrees of Protection provided by Enclosures (IP Code).

F IEC 60947 Standards for LV Switchgear and Control gear.

G IEC 60947-6-1 Automatic Transfer Switching Equipment.

H BS 7671 Requirements for Electrical Installations (IEE Wiring Regulations).

I BSEN 60947-6-1 Automatic Transfer Switching Equipment.

J IEEE C37.90.1 Institute of Electrical and Electronics Engineers.

1.04 SUBMITTALS

A Comply with section 0133 00.

B Provide catalog sheets and manufacturers data showing voltage, switch size, ratings and size of switching and over-current protective devices, operating logic, short circuit ratings, dimensions and enclosure details.

C Submit manufacturer's installation instructions, application conditions and limitations of use stipulated by product testing agency. Include instructions for storage, handling, protection, examination, preparation, installation, and starting of product.

D Submit a one-line diagram of each transfer switch assembly schematic and wiring diagram of the unit.

E Submit factory test reports verifying that the enclosed transfer switches have successfully passed all routine tests. Type tests results shall be submitted, when required by the Engineer.

1.05 QUALITY ASSURANCE

A Manufacturer: Firms regularly engaged in manufacture of enclosed transfer switches of types, ratings and characteristics required, whose products have been in satisfactory use in similar service for not less than 5 years. Preference shall be given to local manufacturers and suppliers/agents.

B Installer: Firms regularly engaged and qualified with at least 5 years of successful installation experience on projects with electrical installation work similar to that required for the project.

C Except where detailed in specifications, all types of enclosed transfer switches shall comply with the requirements of SASO, IEC and BS.



1.06 DELIVERY, STORAGE AND HANDLING

A Comply with section 01 61 00.

B Store in a clean, dry space. Maintain factory wrapping or provide an additional heavy canvas or heavy plastic cover to protect units from dirt, water, construction debris, and traffic.

C Handle in accordance with manufacturer's written instructions. Lift only with lugs provided for the purpose. Handle carefully to avoid damage to internal components, enclosure and finish.

1.07 WARRANTY


1.08 SPARE PARTS AND TOOLS

A Provide two of each special tools required for operation and maintenance of enclosed transfer switches.

PART 2: PRODUCTS

2.01 ACCEPTABLE MANUFACTURERS

A Not used.

2.02 GENERAL

A Transfer switches shall be suitable for satisfactory and prolonged performance under the minimum/maximum ambient conditions and altitude mentioned elsewhere in the specification.

B All transfer switches specified herein shall comply with the requirements of IEC 60947-6-1 and BSEN 60947-6-1.

C Nameplates for enclosed transfer switches shall be made from a corrosion-resistant metal with not less than 10 mm tall raised or engraved characters. The name plate shall be mounted to the front of the enclosure.

2.03 MANUAL TRANSFER SWITCHES

A Manual transfer switches shall be suitable for use as service equipment as shown on the drawings and shall be configured as an electrically-operated, mechanically-held transfer switch.

B Switch position shall be selected by a control switch mounted on the switch cover.

C Manual transfer switches shall be adequately rated for the application indicated and shall have the following minimum characteristics:

1. Voltage: 400/230 Volts AC.

2. Phases/wires: Three phase, four wires.

3. Frequency: 60 Hz.

4. Switched poles: Four.



5. Load inrush rating: As shown on the drawings.

6. Continuous current rating: As shown on the drawings.

7. Interrupting capacity: 150 % of continuous current rating.

8. Withstand current rating: 200 kA rms symmetrical Amperes, when used with class J, and L current limiting fuse (molded case circuit breaker).

2.04 AUTOMATIC TRANSFER SWITCHES

A Automatic transfer switches shall be suitable for use as service equipment and provided as shown on the drawings or schedules and shall be configured as electrically operated, mechanically held transfer switches.

B Automatic transfer switches shall be adequately rated for the application indicated and shall have the following minimum characteristics:

1. Voltage: 400/230 Volts AC.

2. Phases/wires: Three phase, four wires.

3. Frequency: 60 Hz.

4. Switched poles: Four.

5. Type of load: As shown on the drawings.

6. Continuous phase or main current rating: Not less than 125 % of the full load rating of the emergency power source.

7. Fault current withstand rating: Rated to withstand the available fault or short-circuit current available, at a power factor between 0.0 and approximately 0.20, for the duration of cycles for which the current is available before being cleared by a protective device voltage of 400 Volts AC.

8. Overload rating: As required or shown on the drawings.

9. Non-welding of contacts: Rated for non-welding of contacts when used with the feeder over-current devices shown on the drawings and with the available fault current specified herein.

10. Main and neutral contacts: Contacts shall have silver composition and shall be protected by approved arcing contacts for transfer switches having 400 A and larger current rating. Neutral contacts shall have the same continuous current rating as the main or phase contacts.

C Time delay to override monitored source deviation shall be adjustable from 0.5 to 6 seconds and factory set at 1 second. The device shall detect and respond to a sustained voltage drop of 30 % of nominal voltage between any two of the normal supply conductors and initiate transfer action to the emergency source and start the engine-driven generator set after the set time period. The pickup voltage shall be adjustable between 90 and 100 % of nominal and factory set 90 %. The dropout voltage shall be adjustable from 70 to 90 % of the pickup value, and factory set at



70 % of nominal voltage.

D Time delay before transfer to the emergency power source shall be adjustable from 0 to 5 minutes and factory set as recommended by the manufacturer. The device shall monitor the frequency and voltage of the emergency power source and transfer when frequency and voltage is stabilized at or above 90 % of rated values. The pickup voltage shall be adjustable from 85 to 100 % of nominal, and factory set at 90 %. The pickup frequency shall be adjustable from 90 to 100 % of nominal and factory set at 90 %.

E Time delay before return transfer to the normal power source shall be adjustable from 0 to 30 minutes and factory set at 30 minutes. The time delay shall be automatically defeated upon loss or sustained under-voltage of the emergency power source, provided that the normal supply has been restored. Transfer back to normal power shall be made "in phase" or via a timed delay transfer in the unconnected position.

F Two normally open and two normally closed auxiliary transfer switches shall operate when the transfer switch is connected to the normal power source, and two normally open and two normally closed switches shall operate when the transfer switch is connected to the emergency power source.

G Automatic transfer switches shall also be furnished with the following:

1. Engine start contact.

2. Alternate source monitor.

3. Test switch.

4. Close differential protection.

5. Time delay by-pass switch.

6. Manual return-to-normal switch.

H A manual operator shall be provided to permit manual operation of the ATS without opening the ATS enclosure and shall incorporate features to prevent operation by other than authorized and qualified personnel. The ATS shall be designed for use of the manual operator under no load conditions in usual instances, but with the capability of operation under load conditions when necessary.

I The override switch shall by-pass automatic transfer controls so the transfer switch will transfer and remain connected to the emergency power source, regardless of the conditions of the normal power source. If the emergency source fails and the normal source is available, the transfer switch shall automatically retransfer to the normal source.

J A green indicating light shall supervise the normal power source and shall have a nameplate engraved NORMAL.

K A red indicating light shall supervise the emergency power source and shall have a nameplate engraved EMERGENCY.

2.05 AUTOMATIC SEQUENCE OF OPERATION



A Initiate time delay to start alternate source engine generator: Upon initiation by normal source monitor.

B Time delay to start alternate source engine generator: 0 to 6 seconds, adjustable.

C Initiate transfer load to alternate source: Upon initiation by normal source monitor and permission by alternate source monitor.

D Time delay before transfer to alternate power source: 0 to 6 seconds, adjustable.

E Initiate retransfer load to normal source: Upon permission by normal source monitor.

F Time delay before transfer to normal source: Upon permission by normal source monitor.

G Time delay before engine shut down: 0 to 30 minutes, adjustable, of unloaded operation.

H Engine exerciser: Start engine every 7 days; run for 30 minutes before shutting down. By-pass exerciser control if normal source fails during exercising period.

I Alternate system exerciser: Transfer load to alternate source during engine exercising period.

2.06 ADDITIONAL FEATURES

A Indicating lights: Mount in cover of enclosure to indicate NORMAL SOURCE AVAILABLE, ALTERNATE SOURCE AVAILABLE, SWITCH POSITION.

B Test switch: Mount in cover of enclosure to simulate failure of normal source.

C Return to normal switch: Mount in cover of enclosure to initiate manual transfer from alternate to normal source.

D Transfer switch auxiliary contacts: normally open, normally closed.

E Normal source monitor: Monitor each line of normal source voltage and frequency; initiate transfer when voltage drops below 85 % or frequency varies more than 3 % from rated nominal value.

F Alternate source monitor: Monitor alternative source voltage and frequency; inhibit transfer when voltage is below 85 % or frequency varies more than 3 % from rated nominal value.

G In-phase monitor: Inhibit transfer until source and load are within 15 electrical degrees.

H Switched neutral: Overlapping contacts.

2.07 MICROPROCESSOR BASED CONTROLLER

A The automatic transfer switches with or without by-pass isolation shall be provided with a micro-processor based programmable controller to perform all the functions, interlocks, additional features and automatic sequence of operation as described above. Additional functions may also be programmed as recommended by the manufacturer.

B The controller shall direct the operation of the ATS. The controller's sensing and logic shall be controlled by a built-in microprocessor for maximum reliability, minimum maintenance and



inherent serial communications capability.

C The controller shall be connected to the ATS by an interconnecting wiring harness. The harness shall include a keyed disconnect plug to enable the controller to be disconnected from the ATS for routine maintenance.

D The controller shall be enclosed with a protective cover and be mounted separate from the transfer switch unit for safety and ease of maintenance. Sensing and control logic shall be provided on printed circuit boards. Interfacing relays shall be industrial grade plug-in type with dust covers.

E The controller shall meet or exceed the requirements for Electromagnetic Compatibility (EMC) as per applicable standards.

2.08 REMOTE ANNUNCIATION SYSTEM

A Enclosed transfer switches shall have options to give signals to a remote annunciation system for the following conditions:

1. Sources available, as defined by actual pickup and dropout setting of transfer-switch controls.

2. Switch position.

3. Switch intent mode.

2.09 FACTORY TESTING

A Factory testing shall be carried out on all types of completed enclosed transfer switches to be supplied for the project. Overload, endurance and temperature tests shall be conducted in that sequence and within the shortest practicable period of time on the same transfer switch without its de-energization. The test sequence listed below shall be followed for all the enclosed transfer switches supplied:

1. General (as per manufacturers standard procedure).

2. Normal operation.

3. Overvoltage.

4. Under-voltage.

5. Overload.

6. Endurance.

7. Temperature rise.

8. Dielectric voltage (withstand).

9. Contact opening.

10. Instrumentation and calibration of high capacity circuits.



11. Closings.

12. Strength of insulating base and support.

B Tests shall be performed in accordance with the applicable standards. Wiring of each control panel shall be subjected to voltage surge tests as stipulated in IEEE C37.90.1. Impulse withstand rating tests shall also be performed.

C Tests shall be performed and shall demonstrate that the operational sequence of each transfer switch unit conforms to the requirements of the Specification with regard to operating transfer time, voltage, frequency and timing intervals.

PART 3: EXECUTION

3.01 INSPECTION


B Verify that surfaces are suitable for transfer switch installation.

C Verify that site measurements are matching with the space requirements for installation, operation and maintenance of equipment.

3.02 INSTALLATION

A Enclosed transfer switches shall be installed in compliance with the installation requirements for LV power distribution boards given in section 26 24 13 and in accordance with manufacturer's instructions.

3.03 FIELD QUALITY CONTROL


B Prior to energization of transfer switches, check with earth resistance tester, phase-to-phase and phase-to-earth insulation resistance levels to ensure requirements are fulfilled.

C Tests shall be performed to demonstrate that the operational sequence of each enclosed transfer switch unit conforms to the requirements of specification with regard to various transfer timings, voltage, frequency and other characteristics in manual and automatic modes as well as normal, emergency and by-pass modes of operation.

D All the settings and adjustments available with enclosed transfer switches shall be finally adjusted according to the control sequence in accordance with emergency power source and load priority schedules.

3.04 TRAINING




B Provide instruction and training to the Owners staff for the operation and maintenance of the equipment. Provide a minimum of sixteen (16) hours training to be divided between classroom and hands-on training as required by the Owner.

C Agree the training schedule (dates, time, duration of each class, etc.) with the Owner at least one month before the actual training programme is scheduled.

3.05 OPERATION AND MAINTENANCE PROGRAMME


END OF SECTION

SECTION 26 36 00TRAININGProvide instruction and training to the Owners staff for the operation and maintenance of the equipment. Provide a minimum of sixteen (16) hours training to be divided between classroom and hands-on training as required by the Owner.Agree the training schedule (dates, time, duration of each class, etc.) with the Owner at least one month before the actual training programme is scheduled.

OPERATION AND MAINTENANCE PROGRAMME

Documents

SECTION 26 36 00-ENCLOSED TRANSFER SWITCHES.pdf