These units, with integral heat sinks, are driven by either DC or AC Logic signals depending on the order code. Also an analogue 4-20mA input can be specified which gives a linear time proportional output.
In all cases the output is zero voltage switching. High speed fuses are mounted external to the unit for 100 Amps and below, internal above 100 Amps. Spare fuses or complete fuse and fuseholder assemblies can also be ordered separately.
The 7300S has an optional thyristor short circuit and total load failure alarm. An overtemperature shut down is provided for fan cooled units (over 100 Amps). An optional overtemperature alarm is also available. Diagnostic Load Failure detection is an option which alarms on the loss of one or more parallel heating elements (resistive or SWIR).