janitza RCM 202-AB, User Manual And Technical Data

Page: 12 / 68

12
RCM 202-AB
www.janitza.de
12 RCM 202-AB
6 Functions
6.1 Basic functionality
The main functions of the RCM 202-AB are:

Residual current measurement via a connected current measurement trans-
former (max. 2 current measurement transformers)

Transformer connection monitoring for wire breaks or short circuit per channel

Effective value measurement (true RMS)

Parallel measured value recording

Evaluation of fault currents (residual currents) type A and B according to IEC
62020

Detection of sinusoidal residual fault currents with frequencies up to 20 kHz
(type B+)

Measured value and extreme value storage with time stamp

Parameterizable alarm threshold for alarm message per channel

Parameterizable warning threshold (e.g. prewarning) for warning message per
channel

Parameterizable delay times:

Delay time for warning and alarm messages

Reset delay time for warning and alarm messages

Operating and error messages shown on the display

Communication via Modbus (RS485 interface/Modbus RTU)

Evaluation possibility with the help of the GridVis
®
monitoring system or a dis-
play and evaluation device
6.1.1 Residual current monitoring principle
The fault currents (residual currents) flowing to ground or other paths are recorded
via the connected current measurement transformers.
For example:

Outflow-related residual currents (consumers and systems)

Stray currents in TN-S systems (PEN and N conductors)