Rockwell Automation 140U N-Frame Circuti Breakers Instruction Leaflet for N-Frame Circuit Breakers - Manual (Page 11)

Page 11
Fig. 5-2 Connection Diagrams Ground Fault Breaker - Figure indicates normal feed installation.
Neutral sensor is wired identically for reverse feed applications.
Ground fault circuit breakers detect ground fault currents
through residual sensing (they are not designed to use
source ground or zero sequence ground fault sensing
methods). If the system neutral is grounded, but no
phase to neutral loads are used, the neutral current sen-
sor is not necessary.
If the system neutral is grounded and phase or neutral
loads are used, then the neutral current sensor (see
Fig. 5-1) must be used. It should be connected to the
breaker according to Fig. 5-2.
The neutral sensor has the same ratio as the breaker cur-
rent sensors.
Note: The polarity of the sensor connections is criti-
cal. Always observe the polarity markings on the
installation drawings. To insure correct ground fault
equipment performance, conduct field test to comply
with National Electric Code requirements under arti-
cle 230-95(C). See section 7 for testing instructions.
6. INSPECTION AND FIELD TESTING
The molded case circuit breakers are designed to
provide years of almost maintenance-free operation. The
following procedure describes how to inspect and test a
circuit breaker in service.
Inspection
Circuit Breakers should be inspected periodically. This
inspection can be best done during normal equipment
maintenance periods when no voltage to the equipment
is available. The inspection should include the following
checks 6-1 through 6-8.
VOLTAGES IN ENERGIZED EQUIPMENT CAN CAUSE
SEVERE PERSONAL INJURY OR DEATH. BEFORE
INSPECTING THE CIRCUIT BREAKER IN AN ELEC-
TRICAL SYSTEM, MAKE SURE THE CIRCUIT
BREAKER IS SWITCHED TO THE
OFF POSITION
AND THAT THERE IS NO VOLTAGE PRESENT
WHERE WORK IS TO BE PERFORMED. SPECIAL
ATTENTION SHOULD BE PAID TO REVERSE FEED
APPLICATIONS TO ENSURE NO VOLTAGE IS
PRESENT.
WARNING
40752-093(1) Effective 5/02