OPERATION SUMMARY - Section 3
MTS-3000 SERIES OPERATION AND REFERENCE MANUAL 3-25
CU M004 01A
###################################
0$17$
#
7(67
#
6<67(06
4.
Enable the AC outputs by pressing the ENABLE button in the Control section of the CM.
5.
Press FAULT momentarily to enter Dynamic Fault Mode. When the AC current element of the relay
under test closes its contact, the DC current passing through the contact will pick up the DC target and
force the transition from FAULT to POSTFAULT. The TRIP LED in the CONTROL section will light,
and the AC current to the relay will turn off. The operation indicator LED on INPUT 1 should stay on,
as will the audible tone indicator if selected to on, since the auxiliary contacts of the target relay in
parallel with the AC contact remain picked up.
6.
Press the ON pushbutton of the DIGITAL I/O module to turn off the DC current. This will drop out the
seal-in relay, as indicated by the INPUT 1 LED and tone turning off.
3.3.10 Differential Relay - Independent Coil Type
Many solid state current differential relays have independent coils for the two current inputs. This section
describes how to perform standard tests on this type of relay.
FIGURE 3.17 INDEPENDENT COIL DIFFERENTIAL RELAY TEST
3.3.10.1 SLOPE TEST.
Connect the relay, as shown above. The dotted connection between A and C channel outputs may be used
if slope checks are to be done at very high current levels. Connections are also shown for DC voltage
supply to the relay if it requires auxiliary power.
1.
Select slope display mode by entering the following key sequence: MENU | Settings | Display Optns |
Slope | 2wdg 87T style, followed by MENU again.
