ABB REL670 Installation And Commissioning Manual page 120

6.7.6
6.7.7
6.7.8
112
Current protection
Verifying instantaneous back-up trip at "CB faulty" condition
Applies in a case where signal "CB faulty and unable to trip" is connected to input CBFLT.
Procedure
1. Repeat the check of back-up trip time. Disconnect current and start
input signals.
2. Activate the input CBFLT. The output CBALARM (CB faulty alarm)
should appear after set time tCBAlarm. Keep the input activated.
3. Apply the fault condition, including start of BFP, with current above
set current value.
4. Verify that back-up trip is obtained without intentional delay, e.g.
within 20 ms from application of start.
5. Disconnect injected AC and input signals.
Verifying the case FunctionMode = Contact
It is assumed that re-trip without current check is selected, RetripMode = No I> check.
Procedure
1. Set FunctionMode = Contact
2. Apply input signal for CB closed to relevant input or inputs CBCLDL*
3. Apply input signal, or signals for start of BFP. The value of current
could be low.
4. Verify that re-trip and back-up trip are achieved after set times.
5. Disconnect the start signal(s). Keep the CB closed signal(s).
6. Apply input signal(s), for start of BFP. The value of current could be
low.
7. Arrange disconnection of CB closed signal(s) well before set
back-up trip time t2 .
8. Verify that back-up trip is not achieved.
9. Disconnect injected AC and start input signals.
Verifying the function mode "Curr&Cont Check"
To be made only when FunctionMode = Curr and Cont is selected. It is suggested to make the
tests in one phase only, or at three-phase trip applications for just three-phase tripping.
Checking the case with fault current above set value IP>
The operation shall be as in FunctionMode = Current.
Procedure
1. Set FunctionMode = Curr&Cont Check
2. Leave the inputs for CB close inactivated. These signals should not
influence.
Chapter 11
Verifying settings by secondary
injection