Effective 8/13/99
Page 22
I.L. 70C1037H02
CAUTION
TESTING A CIRCUIT BREAKER WHILE IT IS IN-
SERVICE AND CARRYING LOAD CURRENT IS
NOT
RECOMMENDED.
TESTING OF A CIRCUIT BREAKER THAT RESULTS IN
THE TRIPPING OF THE CIRCUIT BREAKER SHOULD
BE DONE ONLY WITH THE CIRCUIT BREAKER IN
THE TEST OR DISCONNECTED CELL POSITIONS OR
WHILE THE CIRCUIT BREAKER IS ON A TEST
BENCH.
5.2 When to Test
Testing prior to start-up can best be accomplished with
the breaker out of its cell or in the Test, Disconnected, or
Withdrawn (or Removed) cell positions.
NOTE: Since time-current settings are based on desired
system coordination and protection schemes, the protec-
tion settings selected and preset in accordance with
Section 4 should be reset to their as-found conditions if
altered during any routine test sequence.
5.3 Functional Field Testing
CAUTION
PERFORMING TESTS WITHOUT THE CUTLER-
HAMMER-APPROVED TEST KIT MAY DAMAGE THE
DIGITRIP UNIT.
Use the test receptacle to verify a functional load test of a
major portion of the electronic circuitry of the Digitrip and
the mechanical trip assembly of the breaker. The testing
can determine the accuracy of the desired trip settings by
performing Long Delay, Short Delay, and Ground Fault
functional tests. The Cutler-Hammer-approved test kit is
listed below.
Model
Test Kit
Digitrip DT20 family
Test Kit (140D481G02R, 140D481G02RR,
140D481G03, or G04) with Test Kit
Adapter 8779C02G04
The test port is located on the front left-hand corner of the
DT20 units (see Figure 1.1). To access the port, remove
the plexiglass cover from the front of the circuit breaker.
Using a small screwdriver, gently pry up on the test port
cover to remove this item.
CAUTION
BEFORE PLUGGING A TEST KIT INTO THE TEST
PORT, PLACE THE LTM JUMPER IN THE INACTIVE
POSITION (SEE FIGURE 4.3). AFTER TESTING, RE-
TURN THE LTM JUMPER TO ITS ORIGINAL POSITION.
The test kit authorized by Cutler-Hammer for use with the
Digitrip units plugs into the test port of the unit and pro-
vides a secondary injection test that simulates the current
transformer. Existing test kits, styles 140D481G02R,
140D481G02RR, 140D481G03 or G04, along with the
Magnum Test Kit Adapter 8779C02G04, can be used to
test the trip unit and breaker.
5.4 Performance Testing for Ground Fault Trip Units
5.4.1 Code Requirements
The NEC, under Article 230-95-C, requires that any
ground fault protection system be performance tested
when first installed. Conduct tests in accordance with the
approved instructions provided with the equipment. Make
a written record of this test and make the results available
to the authority having inspection jurisdiction.
5.4.2 Standards Requirements
As a follow-up to the basic performance requirements
stipulated by the NEC, UL Standard No. 1053 requires that
certain minimum instructions must accompany each
ground fault protection system. These statements (Section
5.4.3), plus a copy of the record forms (Figures 8.1, 8.2,
and 8.3), are included as part of this Instructional Leaflet.
5.4.3 General Test Instructions
The interconnected system must be evaluated only by
qualified personnel and in accordance with the equipment
assembler’s detailed instructions.
To avoid improper operations following apparently correct
simulated test operations, the polarity of the neutral sensor
connections (if used) must agree with the equipment
assembler’s detailed instructions. Where a question
exists, consult the specifying engineer and/or equipment
assembler.
