GE L30 Instruction Manual page 597

CHAPTER 9: COMMISSIONING
6. At the remote relay, make the following changes in the
ELEMENT  CURRENT DIFFERENTIAL
: "Enabled"
CURRENT DIFF DTT
7. At the Local relay, make the following changes in the
CONTACT OUTPUT N1 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
menu of both relays:
DIFFERENTIAL
: "Disabled"
CURRENT DIFF FUNCTION
14. At the Remote relay, set
SETTINGS  INPUTS/OUTPUTS  CONTACT OUTPUT N1  CONTACT OUTPUT N1 OPERATE
the
CURRENT DIFF KEY DTT
15. At the Local relay, observe under the
, and are "Off".
N2 N3
16. At the Remote relay, set
SETTINGS  TESTING  FORCE CONTACT INPUTS  FORCE Cont Ip N1
17. At the Local relay, observe under
are now "On".
18. At both the Local and Remote relays, return all settings to normal.
9.1.4.2 Final tests
As proper operation of the relay is fundamentally dependent on the correct installation and wiring of the CTs, it must be
confirmed 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
ACTUAL VALUES  METERING  87L DIFFERENTIAL CURRENT
observed and conclusions of proper relay interconnections can be made.
L30 LINE CURRENT DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL
menu:
SETTINGS  INPUTS/OUTPUTS  CONTACT OUTPUT N1
: "87L DIFF RECVD
DTT"
ACTUAL VALUES  STATUS  CONTACT OUTPUTS  Cont Op N1
ACTUAL VALUES  STATUS  CONTACT OUTPUTS  Cont Op N1
SETTINGS  GROUPED ELEMENTS  LINE DIFFERENTIAL ELEMENT  CURRENT
operand.
ACTUAL VALUES  STATUS  CONTACT OUTPUTS
ACTUAL VALUES  STATUS  CONTACT OUTPUTS
SETTINGS  GROUPED ELEMENTS  LINE DIFFERENTIAL
that
menu where all current magnitudes and angles can be
TESTING
menu:
is in the "Off" state.
is now in the "On" state.
to
menu that
CONTACT OUTPUT N1
to "Closed".
, , and
CONTACT OUTPUT N1 N2
,
N3
9
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