The BDCA218 is for monitoring of DC and true RMS AC currents from 5 to 6000A and provides a normally open relay output. Internal coding plugs are used to use to program the measurement range from 10 to 100% of the CT used making the relay trip point easier to set. The dead-band will then be a percentage of the selected range. Current is detected by means of a toroidal Hall Effect sensor, providing total isolation and true waveform transfer. This is particularly useful for low voltage systems, where the traditional DC-Shunt method is not acceptable. To accommodate pulsing current or high harmonic contents the filter constant can be set by coding plugs. The input output and supply are fully isolated. Trip status is indicated by front mounted LED. For external CT version the SET adjustment is accessible from the TOP. For top mounted CT the SET adjustment is on the lower narrow edge.