3UG458. insulation monitoring relay
9.4 3UG4582/3UG4583 insulation monitoring relays
3UG4 / 3RR2 monitoring relays
260 Manual, 05/2016, NEB927043002000/RS-AC/004
The voltage source is the secondary side of an isolating transformer that galvanically isolates the system and the
The insulation resistance of this motor feeder is always monitored when the motor is switched off. If the motor
contactor drops out, the two NC contacts connect the measuring circuit with the motor cables.
The 3UG4583-1CW30 insulation monitoring relay permanently monitors the insulation resistance of the remaining
system with all connected loads.
Image 9-11 Monitoring for ground fault/insulation fault with different load circuits
Note
The maximum cable length of the control cables is 50
m or 100 pF/m.