The AC and pulsed DC sensitive residual current monitor RCM420-D (Type A) from Bender 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. In addition, the device can be used to monitor single conductors, such as PE conductors, N-PE connections and PE-PAS connections.
The prewarning stage (50…100 % of the set response value IΔn2) 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.
AC and pulsed DC sensitive residual current monitor Type A according to IEC 62020
r.m.s. value measurement (AC)
Two separately adjustable response values
Frequency range 42…2000 Hz
Start-up delay, response delay and delay on release
Restart function
Digital measured value display via LC display
Measured value memory for operating value
CT connection monitoring
LEDs: Power On, Alarm 1, Alarm 2