18
Instruction Leaflet
I. L. 29-886B
Effective August 2011
Instructions for Digitrip RMS 610 Trip Unit
eaton corporation
www.eaton.com
4 test procedures
4.1 General
DANGER
DO NOT ATTEMPT TO INSTALL, TEST OR PERFORM MAINTENANCE ON
EQUIPMENT WHILE IT IS ENERGIZED. DEATH OR SEVERE PERSONAL
INJURY CAN RESULT FROM CONTACT WITH ENERGIZED EQUIPMENT.
DE-ENERGIZE THE CIRCUIT AND DISCONNECT THE CIRCUIT BREAKER
BEFORE PERFORMING MAINTENANCE OR TESTS.
REFER TO THE APPLICABLE CIRCUIT BREAKER INSTRUCTION LEAFLET
SUPPLEMENT (LISTED IN SECTION 5) FOR COMPLETE INSTRUCTIONS.
CAUTION
TESTING A CIRCUIT BREAKER UNDER "TRIP CONDITIONS" WHILE IT IS IN
SERVICE AND CARRYING LOAD CURRENT, WHETHER DONE BY LOCALLY OR
BY REMOTE MEANS, IS NOT RECOMMENDED.
ANY TRIPPING OPERATION WILL CAUSE DISRUPTION OF SERVICE
AND POSSIBLE PERSONAL INJURY RESULTING FROM UNNECESSARY
SWITCHING OF CONNECTED EQUIPMENT.
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.
4.2 When To Test
Tests can be conducted with the breaker in the "connected" cell posi-
tion while carrying load current . However, as stated in the caution
note in Section 4 .1, good practice will limit circuit breaker in-service
"trip tests", where required, to maintenance periods during times of
minimum load conditions . Testing is accomplished with the breaker
out of its cell or in the "Test", "Disconnected", or "Withdrawn" (or
Removed) cell positions .
otee:
N
Since time-current settings are based on desired system coordination
and protection schemes, the protection settings selected and preset in accor-
dance with Section 3 should not be altered during or as a part of any routine
test sequence .
4.3 Testing Provisions
As illustrated in Figures 1 and 19, an integral test panel is provided
to test the Digitrip RMS 610 Trip Unit .
While the Integral Test Panel does enable one to check the perfor-
mance of many parts of the trip system, including:
•
Microprocessor Functions;
•
Trip Release;
•
Trip Settings;
•
LEDs;
•
Display Panel;
•
Zone Interlocking Function;
•
Power Relay Module; and
•
Rating Plug .
There are some parts it cannot check, for example:
•
Current Sensors;
•
Auxiliary Current Transformers;
•
Bridge Circuits;
•
Calibration Resistors;
•
Analog Override Circuit;
and the functions of these elements are best verified by primary cur-
rent injection testing .
As indicated in Figure 19, Note 1, six different "Test Amps" settings
(1, 2, 3, 6T, 8 and 10 x I
n
) are available for testing the phase ele-
ments of the Trip Unit, and two settings (GF and GFT) are provided
for testing the ground element .
Figure 19. Integral Test Panel (Lower Right Corner of Trip Unit).
CAUTION
A SETTING OF EITHER 6T OR GFT WILL TRIP THE CIRCUIT BREAKER (SEE
SECTIONS 4.1 AND 4.4.2.).
FOR ANY COMBINATION OF THE PHASE PROTECTION SETTINGS, AN
APPROPRIATE "NO TRIP" CONDITION CAN BE SET TO TEST THE LONG
TIME, SHORT TIME, AND INSTANTANEOUS TRIP SETTINGS WITHOUT
TRIPPING THE CIRCUIT BREAKER (SEE SECTION 4.4.1).
IN THE "GF" TEST POSITION, THE LEVEL OF TEST CURRENT, BASED ON I
,
IS ADEQUATE TO DEMONSTRATE THE OPERATING CONDITION OF THE TRIP
UNIT WITHOUT TRIPPING THE CIRCUIT BREAKER. THIS IS A FUNCTIONAL
CHECK ONLY, NOT A CALIBRATION.
4.4 Conducting Tests
To preserve the primary protection function of the Trip Unit, all in-ser-
vice testing whether under "Trip" or "No-Trip" conditions is executed
ONLY if load current values are no greater than 50% x
I
r
(
I
r
= the
Long Delay Current Setting) .
Any attempt to conduct in-service
testing when the load current exceeds 50% of
I
r
, will NOT be
executed by the Trip Unit.
Since the Digitrip RMS 610 Trip Unit is designed to run with control
power from the Power / Relay Module for the display window, all
testing should be conducted with the control power available, either
through the Power Relay Module or, when the breaker is outside the
enclosure, through the Auxiliary Power Module (APM) (see Section
1 .5 and Figure 11) . Although the Trip Unit is designed to perform all
of its Protection Functions without the external control power, and
without the display results of the tests could be confusing . When
performing a single-phase primary current injection test, for exam-
ple, especially when the single-phase current is low, without the
APM it may appear as if the Trip Unit does not respond until the cur-
rent is well-above the set value, leading the tester to believe there is
an error in the Trip Unit when there is none . The reason this occurs
is that the single-phase test current is not a good simulation of the
normal three-phase circuit . If three-phase current had been flowing,
the Trip Unit would actually have performed correctly . Use the APM
for correct Trip Unit performance whenever single-phase current
injection tests are made .
Available "Test Amps" Settings
Breaker Trips
at 6T and GFT
“6T” = Phase Current Test at
and
TRIPS breaker;
Test Amps
"1, 2,
3, 8 or 10"
x
Phase
Current Test
NO
breaker
TRIP;
"GFT"
=
Ground Current Test
and
TRIPS breaker;
"GF"
=
Ground Current Test
Test
NO breaker
TRIP.
See Section
4.4.2 for inser-
Trip
vice test trip limitations.
Reset
Push, then release
button to reset Trip Unit.
Unit
Status
Required following all automatic
trip and test operations.
Push, then release
button to test. Test operation
begins with release of
pushbutton
6xI
n
I
n
n
