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8.7 PLACING THE RELAY IN SERVICE
8.7PLACING THE RELAY IN SERVICE
The procedure outlined in this section is explicitly confined to the operation of the relay, and does not
include the operation of any equipment external to the relay.
NOTE
1.
Cycle through the relay setpoints and set each setpoint in each group to the required value.
2.
Save all the relay setpoints to a file (or print them) for a final inspection to confirm that all setpoints are correct.
3.
Set the relay clock (date and time) if IRIG-B is not used or unavailable.
4.
Clear all historical values stored in the relay. Under subheading
,
USE DATA
CLEAR MAX DMND DATA
, also set
INSTALLATION
5.
Turn off all test voltages, and the power supply to the relay. Remove all test wiring connections, and restore to normal
any panel wiring disturbed for testing.
6.
Perform a complete visual inspection to confirm that the relay is ready to be placed in service. Energize the relay
power supply circuit and check that the Relay In Service LED is on, and that the Self-Test Warning LED is off, estab-
lishing that the relay is operating normally.
7.
For complete on-load checking of the relay, it is required to supply load current to the relay in a known direction of
power flow, with a known approximate value of power factor. The load current should be high enough to be certain that
the main CTs are connected correctly. The power system should be arranged to fulfill these conditions before the
feeder to which the relay is connected is energized. Advise operators of the possibility of a trip on initial energization.
1.
If possible, before closing the feeder breaker to supply load, energize the VT circuit to which the relay is connected.
Check that all relay measurements are as expected. Under
<Magnitude>,
AB: BC: CA:
<Magnitude in kV>,
AGE:
sor>,
PHASE A-N VOLTAGE:
<Phasor>,
VOLTAGE:
2.
To have an immediate indication upon closing of the load level and whether some overcurrent protection is operating,
before closing the feeder breaker display the
3.
After the feeder circuit breaker is closed and the feeder is carrying load current, check that all relay measurements are
as expected. Under subheading
<Magnitude>,
A: B: C:
<Phasor>,
GND CURRENT:
<Phasor>, and
CURRENT:
4.
Under subheading
8
ues (for single and three-phase values) are as expected.
5.
Verify the
A2 METERING
6.
It is very important to confirm that the input CTs are connected properly to provide correct directional control and
metering calculations. A first check of this connection is to note that the values of watts and vars as calculated by the
relay have the correct sign. This is done by comparing the relay measurements, which are signed by the conventions
shown in Figure 6–3: Power Quantity Relationships on page 6–8, to the known feeder load characteristics.
7.
After some time has passed, dependent on feeder load and demand time interval settings, check the following mea-
sured values: Under
,
WATTHOURS
NEGATIVE WATTHOUR COST
8.
Under subheading
PHASE A CURRENT DMND
9.
Under subheading
values.
8-56
Courtesy of NationalSwitchgear.com
, and
CLEAR EVENT RECORDER DATA
RESET TRIP COUNTER DATA
AVERAGE LINE VOLTAGE:
LINE A-B VOLTAGE:
<Phasor>,
PHASE B-N VOLTAGE:
<Phasor>, and
NEG SEQ VOLTAGE:
A2 METERING
A2 METERING
AVERAGE CURRENT:
<Phasor>,
SENSTV GND CURRENT:
ZERO SEQ CURRENT:
, verify that
A2 METERING
PWR
FREQ
SYSTEM FREQ
, verify the
A2 METERING
ENERGY
,
POSITIVE VARHOURS
A2 METERING
DMND
PHASE A(C) CURRENT
values.
A2 METERING
DMND
REAL PWR
750/760 Feeder Management Relay
S1 RELAY SETUP
to "Yes". Under subheading
and
RESET ARCING CURRENT DATA
A2 METERING
VOLTAGE
<Magnitude>,
AN: BN: CN:
<Phasor>,
LINE B-C VOLTAGE:
<Phasor>,
PHASE C-N VOLTAGE:
ZERO SEQ VOLTAGE:
CURRENT
% OF LOAD-TO-TRIP
, verify the following actual values:
CURRENT
<Magnitude>,
PHASE A(C) CURRENT:
<Phasor>,
POS SEQ CURRENT:
<Phasor>
,
REAL PWR
REACTIVE PWR
actual value is as expected.
POSITIVE WATTHOURS
, and
NEGATIVE VARHOURS
, verify the
LAST PHASE A(C) CURRENT DMND
, verify the
LAST REAL PWR DMND
8 COMMISSIONING TESTS
8.7.1 DESCRIPTION
, set
CLEAR DATA
CLEAR ENERGY
S1 RELAY SETUP
to "Yes".
8.7.2 ON-LOAD TESTING
, verify the following:
<Magnitude>,
AVERAGE PHASE VOLT-
<Phasor>,
LINE C-A VOLTAGE:
<Phasor>,
<Phasor>
actual value.
<Phasor>,
NEUTRAL CURRENT:
<Phasor>,
,
and
APPARENT PWR,
PWR FACTOR
,
,
POSITIVE WATTHOUR COST
values.
and
MAX REAL PWR DMND
GE Multilin
<Pha-
POS SEQ
NEG SEQ
val-
NEGATIVE
and
MAX
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