Local-Remote Relay Tests - GE L90 Instruction Manual

11.1 TESTING
11
a) DIRECT TRANSFER TRIP (DTT) TESTS
The direct transfer trip is a function by which one relay sends a signal to a remote relay to cause a trip of remote equipment.
The local relay trip outputs will close upon receiving a direct transfer trip from the remote relay. The test procedure is as fol-
lows:
1. Ensure that relay will not issue any undesired signals to other equipment and all previous tests have been completed
successfully.
2. Cycle power off/on in both relays.
3. Verify and record that both relays indicate In Service on the faceplate display.
4. Make the following setting change in the
RENT DIFFERENTIAL
CURRENT DIFF
5. Verify and record that both relays have established communications by performing the following status check thorough
the
ACTUAL VALUES
CHANNEL 1(2) STATUS:
6. At the remote relay, make the following changes in the
MENTS CURRENT DIFFERENTIAL
CURRENT DIFF DTT:
7. At the Local relay, make the following changes in the
CONTACT OUTPUT N1 OPERATE:
CONTACT OUTPUT N2 OPERATE:
CONTACT OUTPUT N3 OPERATE:
8. At the Local relay, verify that
9. Apply current to phase A of the remote relay and increase until 87L operates.
10. At the Local relay, observe
11. Repeat steps 8 through 10 for phases A and B and observe Contact Outputs N2 and N3, respectively.
12. Repeat steps 8 through 11 with the Remote and Local relays inter-changed.
13. Make the following setting change in the
RENT DIFFERENTIAL
CURRENT DIFF
14. At the Remote relay, set
the
CURRENT DIFF KEY DTT
15. At the Local relay, observe under the
, and are "Off".
N1 N2 N3
16. At the Remote relay, set
17. At the Local relay, observe under
are now "On".
N3
18. At both the Local and Remote relays, return all settings to normal.
b) FINAL TESTS
As proper operation of the relay is fundamentally dependent on the correct installation and wiring of the CTs, it must be con-
firmed that correct data is brought into the relays by an on-load test in which simultaneous measurements of current and
voltage phasors are made at all line terminals. These phasors and differential currents can be monitored at the
UES METERING
clusions of proper relay interconnections can be made.
11-4
SETTINGS
menu of both relays:
"Enabled"
FUNCTION:
STATUS CHANNEL TESTS
"OK"
menu:
"Enabled"
"
87L DIFF RECVD DTT A
"
87L DIFF RECVD DTT B
"
87L DIFF RECVD DTT C
ACTUAL VALUES
ACTUAL VALUES
SETTINGS
menu of both relays:
"Disabled"
FUNCTION:
SETTINGS INPUTS/OUTPUTS
operand.
ACTUAL VALUES
SETTINGS TESTING
ACTUAL VALUES
menu where all current magnitudes and angles can be observed and con-
87L DIFFERENTIAL CURRENT
L90 Line Current Differential System
GROUPED ELEMENTS
menu:
SETTINGS GROUPED ELEMENTS
SETTINGS INPUTS/OUTPUTS
"
"
"
STATUS CONTACT OUTPUTS
STATUS CONTACT OUTPUTS
GROUPED ELEMENTS
CONTACT OUTPUT N1
STATUS CONTACT OUTPUTS
FORCE CONTACT INPUTS
STATUS CONTACT OUTPUTS
11 COMMISSIONING

11.1.4 LOCAL-REMOTE RELAY TESTS

LINE DIFFERENTIAL ELEMENTS
LINE DIFFERENTIAL ELE-
CONTACT OUTPUT N1
is in the "Off" state.
Cont Op N1
is now in the "On" state.
Cont Op N1
LINE DIFFERENTIAL ELEMENTS
CONTACT OUTPUT N1 OPERATE
menu that
CONTACT OUTPUT
to "Closed".
FORCE Cont Ip N1
that
CONTACT OUTPUT N1
ACTUAL VAL-
CUR-
menu:
CUR-
to
, and
N2
GE Multilin