ABB RELION REB670, Руководство по вводу в эксплуатацию

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REB 670
CT3 Current Input
CT1 Current Input
CT2 Current Input
CT4 Current Input
CT5 Current Input
Primary Injection
Test Set
IEC13000228-1-en.vsd
IEC05000307 V2 EN-US
Figure 24: Typical test connection for primary injection, which should confirm
the stability of the main CT connected to current inputs of the IED
For this type of primary injection tests a suitable current source should be applied
across the primary windings of two CTs connected in series as shown in figure
24 .
The testing is normally done on one phase at the time. The currents in the
secondary winding of these CTs are then opposite in phase. The differential current
displayed by the IED should be negligible while the incoming current displayed
should be equal to the value of the injected primary current. The IED must not
issue the trip command during these tests. If it trips or the differential current has a
high value it usually means that there is a wiring problem in the CT circuits
connected to the current input CTx (that is, a differential current equal to twice the
injection current probably indicates wrong polarity of the main CT connected to the
CTx current input). This problem must be solved before the protection scheme is
put in service.
Procedure
1. Connect the test set for primary current injection to the main CTs as shown in
figure
24 .
2. Make sure that current measurement from two used CT inputs are included in
the same differential zone.
3. Inject the primary current in phase L1 and note the incoming and differential
currents on the local HMI of the IED.
The value of the incoming current for phase L1 shall correspond to the
injected primary current. The value of the differential current for phase L1
shall be negligible.
4. Check that the current is present only in the phase being tested.
5. Switch the current off.
6. Check the function in phases L2 and L3 by injecting current in the same way.
1MRK 505 372-UEN A
Section 11
Primary injection testing
Busbar protection REB670 2.2 IEC 163
Commissioning manual