KCM162x & KCM362x - AC EARTH CURRENT GUARD (1 OR 3 CHANNELS)
- For grounded or non-grounded live networks in land, marine and sub-sea installations
- True r.m.s. measurement not affected by heavily distorted Waveforms
- Non-resistive earth current offset function
- Restricted or Unrestricted earth fault detection
- Highest up meter reading on KPM362x, Pathfinder function identifies highest channel
Up to two individual very fast analogue output signals (<50mS), (optional)- DIN96 Slave Indicator with full current scale (optional)
Description
The digitally controlled
KCM162x (
1 channel) and
KCM362x (
3 channels) monitor flow of earth current between a non-grounded (IT) or grounded TN network and its protective earth. Unit can be used for either Restricted or Unrestricted earth fault detection.
The unit reads the level of earth leakage directly in mA. The standard range is 0-150mA. Larger scale values are available, typically 500mA, 1A, 2A, 5A and 10A. The 3-channel KCM362x automatically locks the meter to read the highest of the three channels.
An AC or DC auxiliary voltage is required for the unit. Start of monitoring function is inhibited when auxiliary power is switched on (default 2secs delay). In this way false tripping during power up, caused by initial charging of network spread capacitance, is avoided.
The meter and the triple-zone status LEDs give at a glance the clear safety message:
General
RCD MEASURING PRINCIPLE
Earth current is measured by one (KCM162x) or three (KCM362x) IG-transformers (Core Balance Current Transformer (CBCT). The measuring technique is based on the principle that the sum of the phase currents in a fault free circuit is zero. If an earth fault present, the sum of the phase currents is not zero. This current differential produces a signal from the IG transformer, which is proportional to the earth current. All loaded wires shall go through the CBCT.
OUTPUTS
Up to two individual very fast analogue output signals (optional) proportional to meter reading. If output is used for remote meter reading, we recommend 0-1mA for the slave indicator.
The unit has C/O relay outputs for Warning and Alarm. The Alarm relays are fail to safety configured. A trip LED flashes when the trip level is passed, the relay trips when the delay has elapsed. The timer resets if the fault is removed during countdown. Offset, trip levels and delays are settable on unit front.
OFFSET FUNCTION
Only the resistive (ohmic) earth leakage current is a measure for the
insulation condition between the AC supply and its protective earth. Any
reading of leakage current in a fault free network will be caused by
the networks spread capacitance. An offset potentiometer on the rear
allows normal reactive (capacitive) currents to be ignored.
PATHFINDER FUNCTION
When a warning or alarm trip has operated on a KPM362x, the relevant LED will flash in the following pattern to indicate the highest-up channel producing the trip.
Models (1 channel)
KCM162E
KCM162FA
KCM162FB
KCM162G
KCM162GFA
KCM162GFB
Models (3 channel)
KCM362E
KCM362FA
KCM362FB
KCM362G
KCM362GFA
KCM362GFB
