Hewitt Multi-Alarms are designed to protect engines from low oil pressure, high coolant temperature and low coolant level. All models can utilise existing pressure and temperature switches and most coolant level sensors when available for lower cost and ease of application.Temperature, pressure switches and coolant level sensors are available as required.

Upon an alarm condition, a penetrating audio alarm sounds and a 30 second time delay signal is started. If alarm cancel, system automatically resets. If alarm remains, signal will be sent to engine shutdown device. To restart for an additional 30 seconds run time simply cycle the ignition. An additional input is available for other parameters, i.e. high transmission temperature, with alarm only and no engine shut-down.
Multi-Alarms IV models utilise advanced processor controlled circuit offering additional parameter combinations and precision timing functions with extreme reliability in the same small module.
All models sense coolant level by continuity through the coolant using an AC signal for protection against electrolysis. Eight seconds after coolant falls below sensor alarm occurs and 30 seconds later engine will shut-down. Engine restart only requires cycling of ignition for additional 30 seconds run time but is limited to two 30 second restarts then a 2 minute delay before additional restarts are allowed.

Part Number Description
191-500 Multi Alarm 12 Volt
191-500-1 Multi Alarm 24 Volt
022-011 Pressure Switch
021-113 1/2″ NPT Temp Switch
WLP Water Level Probe (Drill and Screw in)
020-004 Water Level Probe (Solder On)