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Automatic & Filtered AutomaticPower Factor CorrectionUnits
DesignersandManufacturersofPowerFactorCorrectionEquipmentandHarmonicFilters
1016 34 AV SECalgary, AB T2G 1V4Canada
Tel: 403 287 2200 1 800 404 9114Fax: 403 287 3808
contact@electrotekltd. comwww.electrotekltd.com
2
Electrotek Ltd. Automatic and Filtered Automatic Power Factor Correction Units (APFCU / FAPFCU) arecustom designed and manufactured to meet the specific needs of the customers’ electrical distribution.
An APFCU / FAPFCU is the most accurate way to correct a system’s power factor. They are ideal for distributionswhich have a fluctuating load, and distributions with numerous motors. An APFCU / FAPFCU is a centralizedsystem solution, eliminating individual motor capacitors scattered throughout a facility, and their associated costlymaintenance.
How does an APFCU / FAPFCU work?An APFCU / FAPFCU works by constantly monitoring the load on a facility and connecting or disconnectingcapacitive kVAr in order to maintain a preset target power factor.
The kVAr within an APFCU / FAPFCU is divided into groups, which are called steps. Each step includescapacitors, a contactor, HRC fuses, an inrush current limiter (in APFCU’s) or a filtering reactor (in FAPFCU’s). Thebrain of an APFCU / FAPFCU is the controller. It receives the plant load information from a current transformerwhich is located on the main busbar, determines if any changes are required to maintain the target power factor,then adjusts the number of steps connected accordingly.
General Design InformationAs a standard, Electrotek Ltd. APFCU / FAPFCU’s are housed in NEMA 1 enclosures, with other ratings availableupon request.
Enclosures for Electrotek Ltd. APFCU / FAPFCU’s are modular in design, which simplifies any future expansionsto our equipment. If our standard enclosures are not suitable for a particular application, Electrotek Ltd. will designcustom enclosures.
Capacitors - Low Voltage ApplicationsFor low voltage applications, Electrotek Ltd. offers both oil impregnated and dry type capacitors, complete withdischarge resistors. Both lines are manufactured by Vishay (Roederstein), in Germany.
Oil Impregnated ‘Ro’ series capacitor - this capacitor is mineral oil impregnated under vacuum in aseamless tubular can. These capacitors are available in voltage ratings of 525, 690 or999, for use on 208, 480 or 600 volt distributions. This provides additional over voltageand over current protection, and makes them suitable for harmonic contaminatednetworks. This means an increased life expectancy.
Dry Type ‘Rg’ series capacitor - this capacitor is impregnated with an inert gas under vacuum in aseamless tubular can. These capacitors are available in voltage ratings of 240, 525 or690, for use on 208, 480 or 600 volt distributions. This provides additional over voltageand over current protection, and makes them suitable for harmonic contaminatednetworks. This means an increased life expectancy.
Both the ‘Ro’ and Rg’ series capacitors are self-healing, self-disconnecting, true 3 phase capacitors, complete withan over-pressure tear-off fuse. This means all 3 phases will disconnect safely in the case of a failure.Disconnection will result in a slight bulge to the top of the capacitor, making it obvious which capacitor is no longerin working order. The over-pressure tear-off fuse also acts as an internal fuse, providing fuse protection to 10kA.Using HRC fusing on each step eliminates the need for individual external HRC capacitor fuses.
The watt losses of the ‘Ro’ and ‘Rg’ series capacitors are very low: less than 0.25 watts per kVAr.
Capacitors - Medium / High Voltage ApplicationsElectrotek Ltd. also carries capacitors for applications over 1000 volts, manufactured by Vishay (Roederstein), inGermany.
The options available with the ‘R’ series capacitor are almost endless; single phase or three phase, with internalfusing or without internal fusing, indoor or outdoor rated, air cooled or water cooled. Although ‘standard’ 4160 voltcapacitors are stocked in Calgary, almost everything over 1000 volts is a custom order.
3
Inrush Current LimitersSurge Suppression - Each step of capacitors has either an in-line choke coil (for low and medium / high voltageapplications) or a pre-charge coil (for low voltage applications only) which limits inrush currents and over voltagescaused by the switching of capacitors. This increases the life of the step components and prevents voltage spikesfrom affecting other equipment connected to the same distribution system. Inrush current limiters and pre-chargecoils are substituted with reactors in filtered units.
In all Electrotek Ltd. APFCU’s, inrush current limiters are included for each step. Although they are a simple device,they are an invaluable part of our package. Acting as a choke with an inductance of 6-8 mH, they significantlyreduce the inrush current a capacitor would draw during switching.
Filtering ReactorsElectrotek Ltd. filtering (detuning, tuning) reactors are designed specifically for each application, ensuring everycustomer’s FAPFCU is doing the best possible job reducing system harmonics for their application. FAPFCU’s canbe designed and manufactured to target up to seven different tuning frequencies. In addition to the reactors beingdesigned to protect the capacitors (and the rest of the facility), we can design to reduce harmonic distortion to meetutility or IEEE-519 guidelines.
Electrotek Ltd. provides high quality, low loss iron core reactors with taps for easy on site adjustments of filter tuningfrequencies. This makes the FAPFCU flexible for future load considerations, since it can be used with manydifferent harmonic load conditions. Thermostats provide alarms and trip the associated filter step in order to avoiddamage due to prolonged over current and over temperature conditions. All reactors are sized to match themaximum continuous current overload ratings of the capacitors.
ContactorsAs a standard, Electrotek Ltd. uses IEC rated contactors suitable for capacitor switching (not all contactors aresuitable for capacitor switching).
In our FAPFCU’s, Electrotek Ltd. sizes the contactors to match the maximum rms current of the capacitors. Thismeans contactors may be sized larger in our FAPFCU’s than what they would be for an identical step size in ourAPFCU’s, since higher currents and voltages are expected due to harmonic absorption by the filter.
SCR SwitchesFor applications requiring high speed switching of capacitors (filtered or unfiltered) Electrotek Ltd. uses SCRswitching modules suitable for an infinite amount of switching operations. SCR switching modules are used witha special controller which is designed to switch the capacitors on and off at zero crossing of the current sine wavefor a completely transient free system. For more details on high speed designs see our Real Time Power Factorequipment brochure.
FusingAs a standard, all Electrotek Ltd. APFCU / FAPFCU’s are supplied with HRC fusing for each step (3 per contactor).Blown fuse indication and touch safe designs are available upon request.
Disconnecting MeansAs a standard, the disconnecting means for Electrotek Ltd. APFCU / FAPFCU’s are supplied by others and are nothoused inside our enclosure. However, upon request we will include the disconnecting means in our enclosure.
Estamat PFC Digital Microprocessor ControllerThe Estamat PFC digital microprocessor controller is manufactured by Vishay (Roederstein), in Germany,exclusively for the purpose of controlling APFCU / FAPFCU’s. The Estamat controller automatically adjusts theamount of capacitance energized based on continuous measurements of the reactive power of the system. It willmaintain a power factor within 1% of the target power factor. In automatic startup mode, the controller will programitself, allowing unassisted startup.
The Estamat controller displays the individual harmonic current distortion on the main bus bar up to the 17th
harmonic. It also has provisions for communications and full remote control via RS232 or RS485 Modbus RTU.
Switching Options with the Estamat PFC Digital Microprocessor ControllerThe Estamat controller is a 12 step controller with settings for linear or circular switching, as well as single or doublestep switching.
When each step of an APFCU / FAPFCU is equal in kVAr, the unit is described as being single step switched. Forexample; a 100 kVAr unit could be designed with 5*20 kVAr steps. With each step being the same size, thisswitching style also incorporates circular switching. This means the first step energized is the first step de-energized. This switching method results in an extended life for all mechanical and electrical components, sincethere is even wear on all the capacitor steps.
When the steps of an APFCU / FAPFCU are not equal in kVAr, the unit is described as being double step switched.These units are designed with steps sized as multiples of one another. For example; a 100 kVAr unit could bedesigned with 1*20 kVAr and 2*40 kVAr steps. This is a 1:2:2 switching ratio; the unit would have 3 steps, but 5switching increments, as it can still achieve 20, 40, 60, 80 or 100 kVAr online. This unit can also incorporate circularswitching with the steps of equal kVAr size. Double step switching is particularly economical in applications wherea small step size is required due to small load changes, but the total kVAr size of the bank is relatively large.
Examples of these two switching options are illustrated below, in Table 1.
kVAr required
0 kVAr 20 kVAr 40 kVAr 60 kVAr 80 kVAr 100 kVAr
Single Step Switched Unit,steps on line
no steps 1*20 2*20 3*20 4*20 5*20
Double Step Switched Unit,steps on line
no steps 1*20 1*40 1*20 and1*40
2*40 1*20 and2*40
Table 1
In Table 1, as the load increases and the kVAr requirements slowly change from 0 kVAr to 100 kVAr, the contactorsin the single step switched unit would operate a total of 5 times. The contactors in the double step switched unitwould have operated 7 times. However, if the load increases and the kVAr requirements quickly change from 0kVAr to 100 kVAr, the contactors in the single step switched unit will still operate 5 times, but the contactors in thedouble step switched unit will only operate 3 times.
Since the 20 kVAr step in the double step switched unit operates in a linear mode, this 20 kVAr step would requirea new contactor approximately 33% sooner than the circularly switched 40 kVAr steps in the same APFCU /FAPFCU. With the double step switched unit having only 3 steps, rather than 5 in the single step switched unit,it has fewer contactors, fuses, fuse holders, inrush current limiters or filtering reactors, and possibly a smallerenclosure; resulting in a lower initial cost but could require maintenance more often.
If you think an Electrotek Ltd. APFCU / FAPFCU may benefit your facility, please contact us. Using a copy of yourlast 12 power bills, we can conduct a preliminary evaluation. With this we can tell you how much kVAr your facilityrequires, and your resulting annual savings. This is a no charge / no obligation service. Calculations can be donewith fewer bills, if the last 12 are not available.
If the preliminary evaluation indicates an APFCU / FAPFCU is suitable for your facility, we will provide you with acomplete design. An Electrotek Ltd. solution. Your solution.
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1016 34 AV SE Calgary, AB T2G 1V4 CanadaTel: 403 287 2200 Toll free: 1 800 404 9114Fax: 403 287 [email protected]
Real TimePower Factor Correction Units(Transient Free Switching)
DesignersandManufacturersofPowerFactorCorrectionEquipmentandHarmonicFilters
1016 34 AV SECalgary, AB T2G 1V4Canada
Tel: 403 287 2200 1 800 404 9114Fax: 403 287 3808
contact@electrotekltd. comwww.electrotekltd.com
Include iron core reactors to limit the inrush current
Include Iron core reactors that detune the network to preventresonance and absorb up to 50% of the 5th harmonic
Individually designed to absorb the 5th and 7th harmonics.
Transient Free capacitor group switching, using electronicswitching elementsPrevents damage to sensitive electronic equipmentSaves energyHarmonic filtrationAccurate power factor control, even in the presence ofharmonicsDramatically increases the life expectancy of switchingelements and capacitorsConsiderably lower temperature rise of capacitors and inductorsdue to unique scan featureBuilt-in three phase network analyzer, measuring all networkparameters including harmonicsUnique self testing and comprehensive reporting feature.
Cycle by cycle reactive power compensation (total acquisitiontime of 5-20mSec)Prevents voltage drop and flickeringUsed for Real Time applications, such as spot welding andmotor start-upEnhances capacity of local generator systems, such asdiesel and windmill generators.
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•
•
•
•
•
•
•
•
•
ADVANTAGES
EQUALIZER & ACTIVAR
EQUALIZER (in addition to the above)
•
•
•
FAST RESPONSE, TRANSIENT FREE
REACTIVE POWER COMPENSATION SYSTEMS
EQUALIZER:A real time transient free system, used to compensate extremelyrapid loads within one cycle (typically 5-20 mSec).
ACTIVAR:A fast transient free system, used to compensate any load within3-4 seconds.
Basic Systems:
Detuned Systems:
Tuned Systems:
•
•
•
TYPES AVAILABLE:
ACTIVAR
The ACTIVAR is a state of the art, electronic switchingdevice designed to replace electromechanically switchedequipment in power factor correction (PFC) systems.
Connection and disconnection of the capacitors to andfrom the network occurs at zero current crossing. Thissmooth connection avoids the transient effects typicallycreated by electromechanically switched PFC systems.The total acquisition time (full compensation of reactivecurrent) is only 3 to 4 seconds which is much fasterthan electromechanically switched PFC systems.
The electronic switches do not wear out or deteriorateduring the switching process and the capacitors are notadversely affected by transients. These advantagescontribute to a much longer life expectancy comparedwith electromechanically switched PFC systems.The power factor is controlled very accurately by meansof an advanced closed loop control & measuring unit,that takes into consideration all three phases and theeffect of harmonics (1 through 63).The ACTIVAR system is equipped with a unique scanfeature that protects capacitors from "exploding" andcontributes to longer life expectancy. This is achievedby reducing overcurrent and overheating in the capacitorswhich may result from harmonics on the mains. Theswitching element can perform an unlimited numberof switching operations. The connection of one groupof capacitors occurs simultaneously with thedisconnection of another group. This operation isperformed every few seconds and engages all capacitorgroups in turn, resulting in a reduction of mean currentdue to the lower ratio of engagement time to cycle time(duty cycle).
FUSES
SWITCHING ELEMENTSIncluding
FIRING CIRCUITS
L2 L3L1
The scan feature, together with the unique reactor design,substantially reduces the temperature rise of the reactorsand protects the cabinet from overheating.
There is an ongoing cumulative reduction of capacityin electromechanically switched PFC systems due to theeffect of transients during connection and disconnection.This can be detrimental to detuned Electromechanicallyswitched systems where the changes in ratio betweenthe capacitors/reactors shift the resonance frequency,which may result in resonance. The ACTIVAR preventsthese conditions.
SCAN Mode
Groups
Time
3 groupsare always engaged
Each group
is engaged
50% of
the time
1 2 3 4 5 6
6
5
4
3
2
1
A C T I V A R
Current
Voltage
The controller isa full measuringdevice, with anLCD display,which measurescycle by cycle allnetwork andinternalparameters.
Power IQ Measurement & Analysis Software (optional)This software can display the system's status as well asthe measurement results on numerous screens runningunder Windows.
Spot Welding Machines - Car Industry
21:33:32 :38 :40 :42 :44 :46 :48 :50 :52 :54 :56 :58 :00 :02 :04 :06 :08
0
300
150
1000
1400
1800
230
220
210 WithWithout
Time
L1-Q
(kVA
r)L1
- Cur
rent
(A)
L1- V
olta
ge (V
)
08:47:35 :36 :37 :38 :39 :40 :41 :42 :43 :44 :45 :46 :47 :48 :49 :50 :51
400
0
3000
2000
1000
230
215
200
L1-Q
(kVA
r)
With
Time
L1- C
urre
nt (A
)L1
- Vol
tage
(V)
Without
Spot Welding Machine - 12mm mesh
Central Compensation of Start-Up Current of Large MotorsLarge squirrel case inductive motors, when connected directly on-line, consumehigh current during the start-up period (six times higher than steady stateoperation). However, if the network is weak, the high current leads to substantialvoltage drops which interfere with other loads, reducing the initial torque andincreasing start-up time.The Equalizer tracks the reactive current, compensates it within one cycle, andprovides the following features:
Applications
Large and rapid variations in reactive power normally occur during spotwelding operations and motor start-up. The Equalizer minimizes the negativeeffects of these loads, resulting in improved power quality and system capacity.
Spot WeldingSpot Welding loads fluctuate extremely rapidly and consume large amountsof reactive power. Resultant voltage sags tend to reduce welding quality andcan impact welding productivity. In addition, these loads often create a highlevel of voltage flickering, which frequently exceed the recommended IEEElimits.High-speed reactive compensation systems clearly offer the following benefits:Improved welding quality, increased process output and elimination offlickering. Significant capital investment is reduced by better utilization ofthe existing infrastructure.
The top and middle graphs demonstrate that the Equalizer prevents voltagedrop and flickering; substantially reduces the current and compensatesreactive energy.
The bottom graphs demonstrate welder output current (car industry). Theoptimal condition is a stable current within a range of 11,000amp. With theEqualizer, the current variations are +/- 200Amp and without the Equalizerthe current variations are +/- 800Amp. A stable current significantly improveswelding quality. Over-current can cause damage to the electrodes as wellas to the material being welded. Undercurrent during welding operationsdeteriorates welding quality.
•
•
•
Mains protection against voltage drops caused by high momentary consumptionof reactive currentCentral starting of all loads, thus avoiding the use of individual startersrequired to protect the mains against voltage dropDirect connection of motor to mains, to obtain maximum torque duringconnection. This feature is unique to The Equalizer system, since starters of all typesreduce the current going through the motor, thereby reducing the starting torque.
MotorCurrent
EqualizerCurrent
The EQUALIZER
Cycles
0.2
0.6
1.0
Acquisition Time
Equalizer Current
1.0
1.0
1.0
1.0
0 2 4 6 8 10 12 14 16 18 20 22 24
Current of slow response system(3 cycles per step)
The Equalizer is a fast response system that is used to compensate any variation inreactive power within one cycle of the network.
Correct compensation using the EqualizerThe top graph demonstrates how the Equalizer compensates the reactive current offast loads with a duration of 14 cycles. Typical acquisition time (full compensationof reactive current) is less than one cycle and the total current is substantially reduced.
Adverse effects of slower response systemsThe bottom graph demonstrates incorrect compensation where the response time is3 cycles for the connection of a single group and the acquisition time required toconnect a total of 4 groups is 12 cycles.Due to the delay in compensation the current is partially reduced and due to thecorresponding delay in disconnection of the capacitor groups there is residual current.The total effect of the compensation system on the current is negative since theaverage current of the load is increased instead of being reduced. This increasesvoltage flickering due to overcompensation.
Correctcompensation
Incorrectcompensation
Total Current with Equalizer
Total Current with slowresponse system
Load Current
Acquisition Time
The CONTROLLER
The Controller is based on a Digital Signal Processor (DSP) and aVLSI component. It includes an LCD display, analog and digitalcircuitry, firing and optional communication cards.
Typical Screens:
POWER IQ Measurement & Analysis Software
This software displays the system's status as wellas the measurement results on numerous screensrunning under Windows. All network parameters,including harmonics up to the 63rd can berecorded at preselected intervals. The durationof the recording is only limited to the size of thecomputer's hard disk. The software can be setto record data based on selected triggers ofvarious network parameters, such as voltage sagsand/or current spikes. The system records beforeand after the trigger event. The software has intra-net and internet support.
Parameter
FrequencyPhase CurrentNeutral CurrentPhase to Phase Current*Phase VoltageNeutral VoltagePhase to Phase VoltageActive Power (kW)Reactive Power (kVAr)Apparent Power (kVA)Power FactorTime of use (TOU) - in, out, net, total:Active Energy (kWh)Reactive Energy (kVARh)THD at Phase CurrentTHD at Neutral CurrentTHD at Phase to Phase CurrentTHD at Phase VoltageTHD at Neutral VoltageTHD at Phase to Phase VoltageHarmonics of Phase CurrentHarmonics of Neutral CurrentHarmonics of Phase to Phase CurrentHarmonics of Phase VoltageHarmonics of Neutral VoltageHarmonics of Phase to Phase VoltageWaveforms of Phase CurrentWaveforms of Neutral CurrentWaveforms of Phase to Phase CurrentWaveforms of Phase VoltageWaveforms of Neutral VoltageWaveforms of Phase to Phase VoltageSystem LogEvent LogData Log (future)
Phases
CommonL1, L2, L3Neutral
L1-2, L2-3, L3-1L1, L2, L3Neutral
L1-2, L2-3, L3-1L1, L2, L3, TotalL1, L2, L3, TotalL1, L2, L3, TotalL1, L2, L3, Total
TotalTotal
L1, L2, L3Neutral
L1-2, L2-3, L3-1L1, L2, L3Neutral
L1-2, L2-3, L3-1L1, L2, L3Neutral
L1-2, L2-3, L3-1L1, L2, L3Neutral
L1-2, L2-3, L3-1L1, L2, L3Neutral
L1-2, L2-3, L3-1L1, L2, L3Neutral
L1-2, L2-3, L3-1
Loads
MainsMains,Load,Cap.
MainsMains , Load
MainsMainsMainsMains
Mains,Load,Cap.Mains,Load,Cap.Mains,Load,Cap.
MainsMains
Mains,Load,Cap.Mains
Mains , LoadMainsMainsMains
Mains,Load,Cap.Mains
Mains , LoadMainsMainsMains
Mains,Load,Cap.MainsMainsMainsMainsMains
Measurement Level1 2 3 4
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Harmonic Bar Display
Parameters set-up, Help menus 7 Segment Display
Waveform Display
SPECIFICATIONS
POWER SUPPLY:LCD Display Size:LCD Display Resolution:LCD Display Type:FREQUENCY:POWER CONSUMPTION:OPERATING TEMPERATURE:9 ANALOG CHANNELS: 3 current channels for mains load
2 current channels for Equalizer cabinet4 voltage channels
115/230V, 50/60 Hz94x76 mmGraphic 160x128 pixelsFSTN, LED backlight45 to 65 Hz10 VA-20 to +55˚C
RS485/422 communications portELCOM (ELSPEC’s protocol), Modbus / RTUVoltage free N.O. / N.C. relay, max 2A@250VACIP 40144 x 144 x 138 mm1.4kg-25 to +70˚CEN50081-2, EN50082-2, EN55011,EN61000-4-2/3/4/5, ENV50204, ENV50141EN61010-1, EN50439-1, UL508
COMMUNICATIONS:PROTOCOL:ALARM:PROTECTION CLASS:DIMENSIONS:WEIGHT:STORAGE TEMPERATURE:ELECTROMAGNETIC COMPATIBILITY:
SAFETY STANDARDS:
* Unique feature: metering internal current of feeder transformer (delta secondary)
CAPACITOR/REACTOR MODULE
The Equalizer includes custom designed, iron core reactors in serieswith the capacitors.
Iron Core ReactorsThe iron core reactors are manufactured under tight tolerances.The reactors are constructed with a laminated low hysteresis lossesiron core, precision controlled air gaps and copper windings, andhave class H insulation (180˚C).
Systems without tuned or detuned reactors are equipped with limitingreactors designed to limit the inrush current which may develop inthe capacitors during power up. This avoids damage to the switchingelements, fuses and capacitors.
The detuned reactors prevent resonance by shifting thecapacitor/network resonance frequency below the first dominantharmonic (usually the 5th).
A tuned reactor design is available upon request (to absorb most ofthe 5th and 7th harmonics).
CapacitorsThe capacitors are low loss (0.25W/kVAr) MKP type in cylindricalaluminium casing. The MKP capacitor is a metallized polypropylenefilm capacitor with self healing properties and an overpressure tear-off fuse.Capacitor elements for 400V and 480V networks are rated 440V+10%and 525V+10% respectively to cope with harmonics and over-voltage.The capacitors are connected during current zero crossing, andoperated in time sharing (SCAN mode), in order to reduce the effectsof electrical or thermal overload and ensure an extended period ofoperating time (statistical life expectancy: over ten years).
SWITCHING MODULE
The switching module is comprised of solid state switching elements,which provide reliable, high speed, transient free operation. Eachswitching module switches up to three capacitor groups, using doublephase electronic switches for each three phase capacitor group.
SwitchingModule
Iron CoreLimiting Reactor
Iron CoreTuned or DetunedReactor
Capacitors
Capacitor/ReactorModule
Harmonics
Waveforms
Data Logger
Zoom in
Consumption
Real timemeasurement
includingmin & max values
HARMONICS THEORY
IntroductionUtilities generate an almost perfect sinusoidal voltage.Harmonics are created by nonlinear loads such asvariable speed drives, power rectifiers, inverters etc.which cause nonlinear voltage drop and change thesinusoidal nature of the voltage.The term "harmonic" refers to sinusoidal componentsat a frequency which is a multiple (2,3,4,5....) of thefundamental.
The SolutionResonance can occur on any frequency, however inmost cases the current harmonic sources exist at the5th, 7th, 11th, and 13th harmonic.The Equalizer's custom designed reactors, in series withthe capacitors, prevent resonance by shifting thecapacitor/network resonance frequency below the firstdominant harmonic (usually the 5th).
The ProblemWhen the reactive energy is compensated usingcapacitors, there is a frequency at which the capacitorsare in parallel resonance with the mains (highimpedance).
If the resonance frequency of the capacitors-mainsoccurs close to one of the harmonic sources, the currentcan circulate between the supply and the capacitors.This results in high voltage on the line and the capacitorcurrent may exceed the rated current by more thandouble or triple its value.
Phase
-0.5
0.0
0.5
45 90 135 180 225 270 315 360
Square Wave
Phase45 90 135 180 225 270 315 360
1st Harm3rd Harm5th Harm7th Harm9th Harm
Capacitors current with/without reactors
withreactors
withoutreactors
1 2 3 4 5 6 7 n
withreactors
withoutreactors
k
2
4
6
8
10
Shifting resonance frequency below the 5th harmonic
The Result
Amplification factor (k) versus harmonic order (n)
1 2 3 4 5 6 7
k
2
4
6
8
10
Increased N Decreased N
n
C1 CN
L1
SourceImpedance
HarmonicsSource
-
C1 CN
L2 L2NL1
SourceImpedance
HarmonicsSource
1 2 3 4 5 6 7 n
k
2
4
6
8
10
Amplification factor (k) versus harmonic order (n)
Increased N
N=1
Harmonic source frequencies (fn) can be expressed as:fn=fo(PxN 1)Where:fo=Fundamental frequencyP=Number of rectifier/switching elementsN=Integer number 1, 2, 3, ...Example: Six pulse rectifier (P=6), fn = 5, 7, 11, 13, 17, 19 ...
SYSTEM TYPES
EQ300/5-2-400.50-P7-XY ZZ
Tuning frequency:Standard systems:p0: inrush current limiting inductorsDetuned systems:p5.7, p7, p14: for 50Hz networkp6: for 60Hz networkNote: Other values available upon request
Extended features code:Blank: NoneM: MV/HV supportP: Synchronization signalU: Unbalanced control supportS: Single phase feeder
Network frequency:50: 50Hz60: 60Hz
Network phase to phase voltageSuch as: 220, 380, 400, 415, 440, 480, 525…
Switching sequence:1: 1:1:1…2: 1:2:2…4: 1:2:4…
Number of steps: e.g. 3,4,5...12
Total outputin kVAr at nominalvoltage and frequency
System type:EQ: EqualizerAR: Act ivar
Communication0: None1: RS 485 ELCOM Protocol2: RS 485 MODBUS / RTU ProtocolNote: Other options upon request
Measurement level:1 through 4(4 = Most Advanced)
Output (kVAr) Output per step (kVAr)Ratio PART Number
dimensions W x Dx H (mm)400V/50Hz
125
150
175
200
210
250
300
350
360
420
480
480
550
600
660
720
900
1080
1200
1440
480V/60Hz
156
187
219
250
262
312
375
437
450
525
600
600
687
750
825
900
1125
1350
1500
1800
400V/50Hz
25
30
25
40
30
50
60
50
120
60
120
80
50
100
60
120
100
120
100
120
480V/60Hz
31
37.5
31
50
37.5
62.5
75
62.5
150
75
150
100
62.5
125
75
150
125
150
125
150
1:2:2
1:2:2
1:2:4
1:2:2
1:2:4
1:2:2
1:2:2
1:2:4
1:1:1
1:2:2..
1:1:1..
1:1:1..
1:2:2..
1:1:1..
1:2:2..
1:1:1..
1:1:1..
1:1:1..
1:1:1..
1:1:1..
EQ125/5-2-400.50-P7-XYZZ
EQ150/5-2-400.50-P7-XYZZ
EQ175/7-3-400.50-P7-XYZZ
EQ200/5-2-400.50-P7-XYZZ
EQ210/7-3-400.50-P7-XYZZ
EQ250/5-2-400.50-P7-XYZZ
EQ300/5-2-400.50-P7-XYZZ
EQ350/7-3-400.50-P7-XYZZ
EQ360/3-1-400.50-P7-XYZZ
EQ420/7-2-400.50-P7-XYZZ
EQ480/4-1-400.50-P7-XYZZ
EQ480/6-1-400.50-P7-XYZZ
EQ550/11-2-400.50-P7-XYZZ
EQ600/6-1-400.50-P7-XYZZ
EQ660/11-2-400.50-P7-XYZZ
EQ720/6-1-400.50-P7-XYZZ
EQ900/9-1-400.50-P7-XYZZ
EQ1080/9-1-400.50-P7-XYZZ
EQ1200/12-1-400.50-P7-XYZZ
EQ1440/12-1-400.50-P7-XYZZ
800x600x2100
800x600x2100
800x600x2100
800x600x2100
800x600x2100
800x600x2100
800x600x2100
800x600x2100
800x600x2100
1000x600x2100
1000x600x2100
1600x600x2100
1600x600x2100
1600x600x2100
1600x600x2100
1600x600x2100
2400x600x2100
2400x600x2100
3200x600x2100
3200x600x2100
EQ156/5-2-480.60-P6-XYZZ
EQ187/5-2-480.60-P6-XYZZ
EQ219/7-3-480.60-P6-XYZZ
EQ250/5-2-480.60-P6-XYZZ
EQ262/7-3-480.60-P6-XYZZ
EQ312/5-2-480.60-P6-XYZZ
EQ375/5-2-480.60-P6-XYZZ
EQ437/7-3-480.60-P6-XYZZ
EQ450/3-1-480.60-P6-XYZZ
EQ525/7-2-480.60-P6-XYZZ
EQ600/4-1-480.60-P6-XYZZ
EQ600/6-1-480.60-P6-XYZZ
EQ687/11-2-480.60-P6-XYZZ
EQ750/6-1-480.60-P6-XYZZ
EQ825/11-2-480.60-P6-XYZZ
EQ900/6-1-480.60-P6-XYZZ
EQ1125/9-1-480.60-P6-XYZZ
EQ1350/9-1-480.60-P6-XYZZ
EQ1500/12-1-480.60-P6-XYZZ
EQ1800/12-1-480.60-P6-XYZZ
400V/50Hz 480V/60Hz
SINGLE PHASE SYSTEMFeeder:Single phase: Phase to Phase Phase to NeutralCapacitors:Single Phase S
EQUALIZER/ACTIVAROpen/Close loop
BALANCED SYSTEMFeeder:Three phase: 3,4 wire WYE secondary 3,4 wire DELTA secondaryCapacitors:Three Phase -delta connection
UNBALANCED SYSTEMFeeder:Three phase: 3,4 wire WYE secondary 3,4 wire DELTA secondaryCapacitors:Single Phase -L-L or L-N connection U
Standard systems
100V-525V 50/60Hz
Non Standard systems
550V-1000V 50/60Hz
External SignalSynchronizedCompensation POrder
Code
MV , HV networksCompensation viaLV transformer M
Standard balanced systems for 400V/50Hz and 480V/60Hz networks for: Systems with inrush limiting reactors Detuned systems with tuning frequencies P5.7, P6, P7, P14 (up to 100 kVAr per group at 400V/50Hz)•
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Standard systemsWithout Circuit BreakerSingle cabinet 80x60x210 cm (W x D x H), 3 groupsDual door single cabinet 100x60x210 cm, 4 groupsTwo cabinets 160x60x210 cm, 6 groupsThree cabinets 240x60x210 cm, 9 groupsFour cabinets 320x60x210 cm, 12 groups
Non-Standard SystemsWith Circuit Breaker or Load Breaker withor without Busbar ConnectionSingle cabinetDual door single cabinetMechanical structure and dimensions of larger systems are availableupon request.
1016 34 AV SE Calgary, AB T2G 1V4 CanadaTel: 403 287 2200 Toll Free: 1 800 404 9114Fax: 403 287 3808www.electrotekltd.com [email protected]
SYSTEM SPECIFICATIONS
Design:Steel sheet cabinetEnclosure Finish:Epoxy powder coated, in grey (RAL 7032),Internal parts: rust proof aluzincRated Voltage:400V/50Hz and 480V/60HzOther voltage values are available upon requestOutput Rating:Refer to the tableOther output ratings are available upon requestCapacitors:Low loss, self healing, IEC 831-1/2Ambient Temperature:+40˚C max short time+35˚C average in 24 hours+20˚C annual average-10˚C low limitProtection class: IP 20Standards:
ElectromagneticCompatibility:
Safety Standards:
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• FunctionalDiagram
NL3L2L1
FIRINGA
CAP. CT
L1 / L2 / L3/ N
TOHOST
COMPUTER(optional)
TOALARM
Mains CurrentTransformers
Controller
SwitchingModule
FIRINGBOARD
CT 1
CT 2
CurrentTransformers
Group 1 Group 2 Group 3
FIRINGB
FusesMAINS. CT
RS 485ALARM
EN50081-2, EN50082-2, EN55011,EN61000-4-2/3/4/5, ENV50204,ENV50141
EN61010-1, EN50439-1, UL508