This controller is used as a Pump Run Dry protection or to by-pass a non-return valve on startup.
Applying power to the controller, illuminates the Green LED, the Red LED illuminates, the unit relay energises, the state of the contacts changes and the time period is initiated.
Only use 2 Probes (pins 5&7) – the Ground Probe & the High Probe. When both these probes are fully immersed, the relay will stay energised. Should the probes not be immersed before the end of the set time period or become not-immersed after the set time has elapsed, the relay will de-energise, the Red LED will go out & the state of the contacts changes. The controller is reset by removal of power.
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