The residual current monitor RCM475YM2 is designed for fault and residual current monitoring in earthed power supply systems (TN and TT systems) where an alarm is to be activated in the event of a fault, but disconnection must be prevented. Two separately adjustable response values and alarm relays allow to distinguish between prewarning and alarm.

Since the values are measured with measuring current transformers, the device is nearly independent of the load current and the nominal voltage of the system.

• Internal measuring current transformer ø 18 mm
• Two separately adjustable response values
  IΔn2 10 mA…10 A (50…60 Hz)
  IΔn1 30 mA, 10…80 % of IΔn2 (50…60 Hz)
• Response delay for IΔn2 adjustable 0…10 s
• Two separate alarm relays with one changeover contact each
• N / O or N / C operation, selectable

• Two-stage residual current monitoring in earthed two, three or four conductor systems (TN and TT systems)
• Current monitoring of single conductors de-energised under normal conditions
• Socket-outlet circuits for devices which are operated unattended for a long time and which may not fail
• Alarm systems, safety devices
• Air conditioning systems, EDP systems
• Cooling equipment with valuable frozen goods
• Canteen kitchens
• Monitoring of earthed power supplies for stray currents, impact on N conductors