Eaton Digitrip RMS Series, Instructional Leaflet

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TESTING OF A CIRCUIT BREAKER SHOULD BE DONE
ONLY IN THE “TEST,” “DISCONNECTED” OR “REMOVE”
CELL POSITIONS.
6.2 Performance Testing for Ground
Fault Trip Units
6.2.1 Code Requirements
The National Electrical Code under Article 230-95-C requires
that any ground fault protection system be performance
tested when first installed. The test shall be conducted in
accordance with approved instructions provided with the
equipment. A written record of this test shall be made and
shall be available to the authority having inspection jurisdic-
tion.
6.2.2 Standards Requirements
As a follow-up to the basic performance requirements stipu-
lated by the N.E.C. in Section 6.2.1, UL Standards No. 1053
requires that certain minimum instructions must accompany
each ground fault protection system. The following article
plus the test record form illustrated in Figure 9 are intended
to satisfy this requirement.
6.2.3 General Test Instructions
The interconnected system shall be evaluated in accordance
with the equipment assembler’s detailed instructions by
qualified personnel.
The polarity of the neutral sensor connections, if used, must
agree with the equipment assembler’s detailed instructions
to avoid improper operations following apparently correct
simulated test operations. Where a question exists, consult
the specifying engineer and/or equipment assembler.
The grounding points of the system shall be verified to
determine that ground paths do not exist that would bypass
the sensors. The use of high voltage testers and resistance
bridges may be used.
 warNINg
THERE IS A HAZARD OF ELECTRICAL SHOCK OR BURN
WHENEVER WORKING IN OR AROUND ELECTRICAL
EQUIPMENT. ALWAYS TURN OFF POWER SUPPLYING
THE BREAKER BEFORE CONDUCTING TESTS.
Effective July 2010
Instructional Leaflet
IL8700C39-04
Using a low voltage, 0-24 volts, high current, AC source,
apply a test current of 125% of the Digitrip Ground Fault Trip
Unit pickup setting through one phase of the circuit breaker,
as shown in Figure 8a. This should cause the breaker to trip
in less than 1 second, and an alarm indicator should operate,
if one is supplied. Reset the breaker and the alarm indicator.
Repeat the test on the other two phases.
If the system is a 4-wire system with a neutral current sen-
sor, apply the same current as described above through one
phase of the breaker, returning through the neutral sensor,
as shown in Figure 8b. The breaker should not trip, and the
alarm indicator, if supplied, should not operate. Repeat the
test on the other two phases.
If the system is a 3-wire system with no neutral current
sensor, apply the same current as described above through
any two phases of the breaker, with the connections exactly
as shown in Figure 8c. The breaker should not trip, and the
alarm indicator, if supplied, should not operate. Repeat the
test using the other two combinations of breaker phases.
 CauTION
FIELD TESTING SHOULD BE USED FOR FUNCTIONAL
TESTING AND NOT FIELD CALIBRATION OF THE DIGI-
TRIP GROUND FAULT TRIP UNIT.
ANY TEMPORARY CONNECTION MADE FOR THE PUR-
POSE OF CONDUCTING TESTS SHOULD BE RESTORED
TO PROPER OPERATING CONDITIONS BEFORE RE-
TURNING THE BREAKER TO SERVICE.
THE RESULTS OF THE TEST ARE TO BE RECORDED ON
THE TEST FORM PROVIDED (FIGURE 9).
7.0 Record Keeping
For convenience, a trip function record as shown in Figure 10
is included. This record should be filled in giving the indicat-
ed reference information and initial time/current trip function
settings. If desirable, a copy could be made and attached to
the interior of the breaker cell door or other visible location.
Figure 11 is also included as a convenient way of providing a
place for recording test data and actual trip values.
Ideally, sheets of this type should be used and maintained
by those personnel in the user’s organization that have the
responsibility for protection equipment.
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