Testing Of The Short-Circuit Protection; Testing Of The Ground-Fault Protection - ABB REM 610 Operator's Manual

REM 610 REM 610
5.6.1.
5.6.2.
56
Motor Protection Relay
Operator's Manual - ANSI version
For the limited current carrying capacity of the wiring, terminals and
measuring transformers of the relay, refer to the Technical Reference
Manual.

Testing of the short-circuit protection

If proper 3-phase secondary testing equipment is not available for current
generation, the phase unbalance and phase reversal protection functions have to be
out of operation during the test.
When calculating the current to be injected into the phase current energizing inputs,
the calculation should be done on the basis of the following:
The rated current, 1 A or 5 A, of the relay energizing input to be tested
*
The protected unit scaling factor (used for motor full load current compensation)
*
This gives the current to be injected during the test as follows:
Injected current (A) = 2.5 x 50P x Rated current of the energizing input x
*
Protected unit scaling factor
To perform the test, inject the current in all three phase current energizing inputs.
The output contacts, to which the trip signal is routed from the short-circuit
protection function, should be activated on the expiration of the set operate time of
element 50P.

Testing of the ground-fault protection

When calculating the current to be injected into the ground-fault current energizing
input, the calculation should be done on the basis of the following:
The rated current, 1 A or 5 A, of the relay energizing input to be tested
*
This gives the current to be injected during the test as follows:
Injected current (A) = 2.5 x 51N x Rated current of energizing input
*
To perform the test, inject the current in the ground-fault current energizing input.
The output contacts, to which the trip signal has been routed from the ground-fault
protection element, should be activated on the expiration of the set operate time of
element 51N.
1MRS755538