Conducting Tests; Control Power; Not Tripping The Breaker - Eaton Digitrip RMS 510 Instruction Leaflet

Instructions for Digitrip RMS 510 Trip Unit
Breaker Trips
at 6T and GFT
Test A m p s

Test

Trip

Reset
Unit
Status
Figure 19. Integral Test Panel (Lower Right Corner of Trip Unit).

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
Long Delay Current Setting) . Any attempt to conduct in-service
testing when the load current exceeds 50% of I
executed by the Trip Unit.
Since the Digitrip RMS 510 Trip Unit is completely self-powered
using energy derived from the current sensors installed in the circuit
breaker, all in-service tests conducted should be conducted with the
auxiliary control power module, shown in Fig . 10, plugged into the
trip unit . This action will avoid difficulties caused by load current lev-
els that are too low to operate the trip unit .
1. Before starting any test sequence, check the Unit Status
(Green LED) in the lower right corner of the Trip Unit (see Figures
2 and 19) to be sure it is blinking on and off about once each sec-
ond, which indicates that the Trip Unit is functioning normally. In
the event the Unit Status LED is not blinking, install an Auxiliary
Power Module (APM) (see Figure 10), or if you have already
installed one, check to see that it is connected correctly (see
Section 1 .3) .
2. If the circuit breaker is carrying current, check that the current
is not:
a . more than 50% of the Long Delay Current Setting (I
because the Trip Unit will not execute your test instructions
when it senses that the current through the breaker exceeds
the 50% level . If the current through the circuit breaker
increases to a value greater than 50% of the Long Delay
Current Setting, I , the Trip Unit will automatically abort any
r
Trip Unit Test that may be in progress . Should an actual
overload or fault condition occur during an in-service, test
sequence, the protection function will override the test func-
tion, and the circuit breaker will trip automatically in accor-
dance with the actual Time-Current settings .
b . the current is not less than 10% of the breaker frame (or
current sensor) rating; be sure the "GREEN" Unit Status LED
(in the lower right corner of the trip unit (See Figs . 2 and 19)
is blinking on and off (indicating that there is enough current
flowing to provide the power necessary to operate the trip
unit) . In the event the Unit Status LED is either lit "GREEN"
or "OFF" continuously, there is NOT enough current flowing
to power the trip unit; and an APM (See Fig . 10) should be
installed before proceeding with the test .
Available "Test A m p s " Settings
"6T" = Phase Current Test at

6xI and TRIPS breaker;
n
"1, 2, 3, 8 or 10" x I
Phase
n
Current Test NO breaker
TRIP;
"GFT" Ground Current Test
=
and TRIPS breaker;
"GF" Ground Current Test
=
NO breaker TRIP.
See Section 4.4.2 for inser-
vice test t r i p limitations.
Push, then release Trip Reset

b u t t o n t o reset Trip Unit.
Required following all automatic
trip and test operations.
Push, then release

button to test. Test operation
begins w i t h release of
pushbutton
(I = the
r r
, will NOT be
r
);
r
Instruction Leaflet I. L. 29-885D
3. When performing tests on the Long Delay element, be aware
that in addition to the standard protection element, the
Digitrip RMS 510 Trip Unit also has a Long Time Memory
function (LTM), which serves to protect load circuits from
the effects of repeated overload conditions (see Note 1 under
Section 3 .3 Long Delay Time Setting) . The action of the LTM
during primary injection tests and during tests initiated from the
Trip Unit Test Panel under the "TEST AMPS" setting of "6T", will
advance the Long Delay Trip Time if multiple Long Delay Time
tests are performed repeatedly - as one might do in making
single-phase tests on each pole of a breaker in succession, for
example . If there is any question, you may simply wait about
ten (10) minutes after a Long Delay Trip for the LTM to reset .
The LTM is not active during tests initiated from the Trip Unit Test
Panel under the "TEST AMPS" settings of "1", "2", "3", "8", or "10" .
To reset the LTM immediately:
Set the "TEST AMPS" to "1" .
•
Press and release the (Black) "TEST" push-button (timer will be
•
running in the display window), and then
Quickly press and release the "TRIP RESET" push-button
•
before the Trip Unit operates .
Now the LTM will be reset .
•

4.4.1 Control Power

For testing the trip unit, an optional Auxiliary Power Module (Cat .
No . PRTAAPM) as shown in Fig . 7 is recommended . This Auxiliary
Power Module, which operates from a separate 120 Vac supply, may
be used when a drawout circuit breaker is in any of its four cell posi-
tions, i .e ., "Connected", "Test", "Disconnected" and "Withdrawn" (or
"Removed .")
N otee: For Testing Purposes Only: When using an external single phase current
source to test low level ground fault current settings, it is advisable to use
the Auxiliary Power Module (APM) (See Fig . 10) . Especially when the single
phase current is low, without the APM it may appear as if the trip unit does
not respond until the current 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 tests are made .
Plug in the Auxiliary Power Module (Cat . No . PRTAAPM) to insure
control power is available for testing . When the APM is properly con-
nected the "GREEN" Unit Status LED will blink on and off about once
per second .

4.4.2 Not Tripping the Breaker

1 . Place the "TEST AMPS" selector switch (see Figure 19) in one of
the six "No Trip" test settings, i .e ., 1, 2, 3, 8, or 10 x I
2 . Press and release the (Black) "TEST" push-button - the test starts
when the push-button is released . When the timer stops, the lit
"RED" cause of trip LED indicates the protection function which
operated .
3 . Should any of the various protection settings be less than the
selected "No Trip" test value, then the LED related to that func-
tion will turn on signifying successful completion of the test
action .
During the long delay tests the Long Delay LED flashes "RED" .
N otee:
4 . Reset the Trip Unit by pressing and releasing the "TRIP RESET"
push-button; all LEDs lit by the "No Trip" test action should turn
"OFF . In the event that no one resets the Trip Unit after a test, it
will wait for about three (3) hours, and then it will automatically
revert back to its pretest status .
Should an actual overload or fault condition occur during an in-ser-
vice, "No Trip Test" sequence, the protection function will override the
test function, and the circut breaker will trip automatically in accor-
dance with the actual Time-Current settings .
EATON CORPORATION www.eaton.com
Effective August 2011
, or GF .
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