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25 – 5
25.3
Primary Injection Ground Fault Current Testing
Circuit Breakers With 3-Wire Residual Ground Fault Protection
Testing is accomplished by routing current through one phase of the breaker. The Ground Fault Mode switch must be in the up position
(summation symbol) in order for the residual ground fault detection to be tested.
Circuit Breakers using 4-Wire Residual Ground Fault Protection via the External Neutral Sensor (air core)
To test a WL breaker equipped with trip 4-wire residual ground fault protection, the ETU must first be activated by injecting 80-100A through
the breaker itself (Source A). Once the ETU is active, the test current can be injected through the external neutral sensor to verify its con-
nection and polarity (Source B). The external neutral sensor does not provide energy to the ETU to activate it.
Figure 4
The same test can be conducted using a single power source. The ETU must be activated by injecting a minimum of 100A through the
breaker itself. The external neutral sensor does not provide energy to the ETU to activate it. Multiple windings through the external sensor
can be added to create greater imbalances.
Figure 5
ETU
Source A
Source B
Secondary Terminals
X8-9 & X8-10
External Air-Core Sensor on
Neutral Bus
ETU
Source
Secondary Terminals
X8-9 & X8-10
External Air-Core GF Sensor
on Neutral or Ground Bus
Содержание UL 489
Страница 36: ...5 21 Frame size II 3000 A Frame size III 1 Holes 14 mm 0720 1 0721_nu ...
Страница 63: ...7 2 Horizontal connectors 0733_nu top view ...
Страница 64: ...7 3 Rear vertical connectors 0734_nu top view rear view ...
Страница 65: ...7 4 Front connectors 0736_nu front view top view ...
Страница 66: ...7 5 Front connectors and pressure wire terminals 0737_nu top view front view ...
Страница 67: ...7 6 7 2 Frame size II fixed mounted version 0494 3_nu ...
Страница 68: ...7 7 Class C always 0494 5_nu top view rear view ...
Страница 69: ...7 8 2500 0738_nu LH side view front view ...
Страница 71: ...7 10 7 4 Frame size III fixed mounted version 0495 1_nu LH side view ...
Страница 72: ...7 11 0495 2_nu top view top view ...
Страница 73: ...7 12 0495 3_nu top view rear view ...
Страница 75: ...7 14 7 5 Door cut outs fixed mounted circuit breaker Frame size I 0735_nu ...
Страница 76: ...7 15 Frame size II III 0496_nu ...
Страница 77: ...7 16 7 6 Frame size I draw out version 0745_nu ...
Страница 78: ...7 17 0746_nu rear view top view ...
Страница 79: ...7 18 0747_nu bottom view ...
Страница 80: ...7 19 0748_nu ...
Страница 81: ...7 20 0749_nu ...
Страница 82: ...7 21 7 7 Frame size II draw out version 0490 1_ul ...
Страница 86: ...7 25 7 8 Frame size III draw out version ...
Страница 87: ...7 26 ...
Страница 88: ...7 27 ...
Страница 89: ...7 28 7 9 Door cut outs for draw out circuit breakers Frame size I 0750_nu ...
Страница 91: ...7 30 7 11 External sensor for neutral conductor WLNCT2 ...
Страница 92: ...7 31 WLNCT3 ...
Страница 107: ...9 5 I tripping Ground fault tripping ...
Страница 256: ...15 12 Installing FS II and FS III 1 Socket head cap screw M5 with washer and nut 1 2 3 4 6 5 7 8 Size 4 5 Nm 45 lb in ...
Страница 307: ...22 2 Installing the door sealing frame Not for use with fuse carriages Catalog No Door sealing frame WLDSF 1 2 3 ...
Страница 351: ......