A unique, pulsed — and intrinsically safe — electrical signal is generated by the control monitor and is transmitted to the sensors via a coiled cord and optic format plug.When sensors on the transport are dry a signal is returned to the monitor. If the signal meets pre-determined characteristics the monitor goes to a “permissive” state.This “permissive” state closes a set of relay contacts which, in turn, changes the status light on the front of the 8100 series optic rack monitor from red (“non-permissive”) to green (“permissive”) signaling the terminal automation system (T.A.S.).
If the sensor becomes wetted during the loading process, the monitor senses this condition and opens the relay. When the relay is opened, the status light will change to red (“non-permissive”) and stops the“permissive” signal that was being sent to the terminal automation system (T.A.S.).The Model 8130 Optic Monitor with Ground Verification includes displayed status of the optic sensor displaying “permissive” or “non-permissive” status and mode of operation.