Download ECP 11-0310 High Impedance Differential

Document Number: ECP 11-0310
Date: 12/12/2016
HIGH IMPEDANCE DIFFERENTIAL BUSBAR PROTECTION TEST FORM
Substation Name
Substation Number
Circuit
General Data
Manufacturer
CT Ratios
V dc
Trip Supply
Wiring
Insulation resistance (see test form ECP 11-0301)
Inter relay and
cubicle wiring
checked to:
Circuit diagram number ……………………………………….
()
Wiring diagram number ………………………………………..
()
Measure and record lead resistances, using where necessary a leadresistance diagram (see test form ECP 11-0304)
Isolator
auxiliary
switches
()
()
Check continuity of closed auxiliary switches either visually, or,
if not possible, by electrical test methods
()
Check auxiliary switches are silver plated
()
Check that two auxiliary switches in parallel are provided for all
auxiliary switches in CT and relay paralleling circuits, except
where the auxiliary switches have been specifically approved
for the purpose, in which case one only need be used*
()
* The correct setting of auxiliary switches is checked in ECP 11-0303 or ECP 11-0304 as
appropriate.
Mechanical Inspection
Mechanical inspection of the all ac and dc relays is to be recorded on the
secondary injection test sheet, or test form ECP 11-0305, as appropriate
()
DC Relays
All dc tripping, auxiliary and timing relays checked as part of the composite
scheme in accordance with test form ECP 11-0305 and the results obtained
are to be recorded therein
()
THIS IS AN UNCONTROLLED DOCUMENT, THE READER MUST CONFIRM ITS VALIDITY BEFORE USE
Version: 3.0
High Impedance Differential Busbar Protection Test Form
Document Number: ECP 11-0310
Version: 3.0
Date: 12/12/2016
Secondary Injection Test – Supervision Timing Relay
Note, the operating time at the setting voltage, of certain supervision timing relays, may be
considerably in excess of the declared minimum time
Operating Time
Reset
Setting
Measured
Secondary Injection Test – Check and Discriminating Relays and Supervision Relays
Using single phase injection, measure and record at the recommended setting the minimum voltage
at which all Check and Discriminating relays and Supervision relays operate. Injection to be made
across relay and associated stabilising or setting resistors as appropriate. Enter results on the
secondary injection test sheet. Record reset by tick only
© UK Power Networks 2017 All rights reserved
2 of 7
High Impedance Differential Busbar Protection Test Form
Document Number: ECP 11-0310
Version: 3.0
Date: 12/12/2016
Secondary Injection Test – Fault Setting Test
This test need only be carried out if it is impracticable to ascertain the fault setting by primary injection.
Minimum operating current at recommended setting. Injection to be made across the appropriate relay
buswires. All check and discriminating relays are to be checked. Enter results on the secondary injection
test sheet
Actual Voltage
Fault Setting
Setting
Zone or
Recomcircuit
Current to produce
Serial Relay Mech mended
and
Phase
relay operation
No.
Type Check Voltage
Relay
Setting Operate Reset
Function
Equivalent
Secondary
Primary
(A)
(A)
Primary
circuits
connected
during
test
R
Y
B
R
Y
B
R
Y
B
R
Y
B
R
Y
B
R
Y
B
R
Y
B
R
Y
B
© UK Power Networks 2017 All rights reserved
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High Impedance Differential Busbar Protection Test Form
Document Number: ECP 11-0310
Version: 3.0
Date: 12/12/2016
Primary Injection Tests
The details and results of all primary injection tests are to be recorded on test form ECP 11-0303
Local Primary Injection Tests
Ratio and polarity of Discriminating CTs as a group
()
Ratio and polarity of Check CTs as a group
()
Overall Primary Injection Tests
Balance tests to prove correct interconnections between CT groups
()
The busbar protection comparison test form is to be used for these tests.
Note that when the secondary currents associated with Local primary
injections for different primary circuits are measured at a common point, and
the integrity of the associated main and reserve busbar isolator auxiliary
switches and secondary wiring is therefore proved, it will normally only be
necessary to compare the CTs of one phase, to prove the correct polarity of
the CT group under test with respect to the reference CTs. In all other cases
comparison tests are to be carried out on all three phases
()
Primary Injection – Fault Setting Test
If it is impracticable to carry out this test, the fault setting is to be ascertained by secondary injection.
Measure and record the earth-fault setting for each Check and Discriminating relay in each zone or
circuit (as applicable). Measure and record also the setting of the supervision relays
Fault Setting
Circuit
or Zone
Relay
Primary Current (A)
R
Y
B
© UK Power Networks 2017 All rights reserved
Buswire Voltage (V)
R
Y
Primary Circuits
connected during
Test
B
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High Impedance Differential Busbar Protection Test Form
Document Number: ECP 11-0310
Version: 3.0
Date: 12/12/2016
Primary Injection – Main Bar
With the circuits selected to Main Bar measure and record CT currents and relay currents, setting
resistor currents, or buswire voltages
Remarks
B
Discrim
R…
Y
R
Setting
Resistor Currents /
Relay Currents /
Buswire Voltage
B
Discrim
M…
Y
R
B
Check
Y
R
N
Discrim
Y
R
……….
Circuit
N
Check
CT
Secondary
Current
(measured
at test
links)
B
B
Y
R
N
Discrim
B
Y
R
……….
Circuit
N
Check
B
Y
R
Phase Injected
R-R
Reverse
Y-Y
Reverse
B-B
Reverse
Primary Current (Amps)
© UK Power Networks 2017 All rights reserved
5 of 7
High Impedance Differential Busbar Protection Test Form
Document Number: ECP 11-0310
Version: 3.0
Date: 12/12/2016
Primary Injection – Reserve Bar
With the circuits selected to Reserve Bar Measure and record CT currents and relay currents,
setting resistor currents, or buswire voltage
Remarks
B
Discrim
R…
Y
R
Setting
Resistor Currents /
Relay Currents /
Buswire Voltage
B
Discrim
M…
Y
R
B
Check
Y
R
N
Discrim
Y
R
……….
Circuit
N
Check
CT
Secondary
Current
(measured
at test
links)
B
B
Y
R
N
Discrim
B
Y
R
……….
Circuit
N
Check
B
Y
R
Phase Injected
R-R
Reverse
Y-Y
Reverse
B-B
Reverse
Primary Current (Amps)
© UK Power Networks 2017 All rights reserved
6 of 7
High Impedance Differential Busbar Protection Test Form
Document Number: ECP 11-0310
Version: 3.0
Date: 12/12/2016
Comments
Test Equipment
Purpose
Make/Type
Serial Number
Certification
()
All tests have been completed satisfactorily
Contractor Commissioning Engineer (if applicable)
Organisation
Name
Date
Signature
UK Power Networks Commissioning Engineer
Name
© UK Power Networks 2017 All rights reserved
Signature
Date
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