11
be removed. Sealing arrangement is provided in one of the four
knurling screws fitted on the cover. Sealing can be done using a sealing
wire. Thus mechanical interlock is provided to avoid unauthorized
setting change.
2.1 CURRENT TRANSFORMER TAP SELECTION
MIB202 relays are suitable for 1A or 5A application. However the
relays are internally wired for either 1A or 5A as per the customer
requirement. Internal wiring are to be changed (Faston crimp
connections) for changing the relay rating from one to other.
To ensure the current rating of the relay, check the connection of
CT wires connected to the bottom TB (Terminal Block) at the rear of the
chassis as per the following table:
For 1A
Phase
Terminal
No. of TB
Ferrule No. of CT
Wire(Black)
A
1
1A
B
3
3A
HV Side
C
5
5A
A
7
7A
B
9
9A
LV Side
C
11
11A
For 5A
Phase
Terminal
No. of TB
Ferrule No. of CT
wire(Black)
A
1
1B
B
3
3B
HV Side
C
5
5B
A
7
7B
B
9
9B
LV Side
C
11
11B
Following are the steps to change the current rating of the relay from 1A
to 5A.
1)
Identify LV & HV side phases terminal from number strip on
bottom terminal block at the rear of the chassis.
