Interlocking Current-leakage Protection System type ER 600 im

The ER 600im type protection is used to control isolation status in isolated medium-voltage power networks with average voltage of 3.3 kV, as a blocking protection. The measuring circuit of the ER600im protection can interoperate with the controlled network only by means of the integrated set of ER600d chokes and has the following function:

  • Signalling when the insulation condition falls below the set reference value, the controlled release time relay is released, whose contacts signal tripping or prevent reclosing a circuit breaker or a contactor energising a controlled section of the network.
Blokujące Zabezpieczenie Upływowe Typu ER 600 im

Explosion protection

I M2 [Ex ib] I Mb

Ambient temperature
-20°C to +70°C


Rated values

Ingress protection rating

Supply voltage
230 V or 42 V AC ± 20%

Power input
1 VA

Test voltage
24 V DC ±5%

Rated voltage of controlled network
up to 3600 V AC,

Maximum output current of the measuring circuit
Io=0.214 mA

Internal inductance ER600d (U = 25.2 V)
Li = 5500 H

Internal inductance ER600z (U = 25.2 V)
Li = 1930 H

Internal capacity
Ci – negligible

Setting range for network 3.3 kV
220 kΩ ± 20%

Tripping time
<70 ms

2 switching contacts

Switching voltage
max. 250 V AC/DC

Switching current
Imax 5A


ER 600 im – Interlocking Leakage Protection

Other parameters, including intrinsically safe ones, are included in the instruction manual available on the manufacturer’s website.