IMM 8001/8002 – Digital Motor Protection Relay
ICE / CEE
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IMU307-1 GB Ind. B
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3.4. AUXILIARY VOLTAGE CONNECTION
Recommendations :
Before making the connection, it is important to verify that the value of the auxiliary voltage,
considering possible variations, is within the range indicated on the front panel label :
•
low voltage range
19 to 70 V DC or AC
•
high voltage range
85 to 255 V DC or AC
Connection of the auxiliary voltage is done on terminal block ‘A’, terminals A1 and A2. The
connection direction is indifferent.
Connection to the earth is done via terminal 1 of the power terminal block.
3.5. CONNECTION OF THE CURRENTS ( EARTH FAULT)
Phase currents I1 and I3
Choose the suitable relay current inputs depending on the secondary CTs nominal value.
For each phase, the relay has a 1A input and a 5A input, see chapter 3.2.
The parameter range of the relay allows a CT primary nominal value between 10A and 10 000 A.
Characteristics of recommended current transformers :
5 VA
Class 5 P 15.
Caution : comply with the connection direction specified by the connection diagram (the point
represents the direction of the flow of current).
Earth fault current Io
Residual connection mode
In the event of earth fault current measurement in residual connection mode, it will be required to
have 3 CTs instead of 2.
In this case, preferably choose use of operating level Io> which is inverse time to let through earth
fault currents produced on motor starting.