EAW SO Self-Hold Thermal Cut-outs

SO self-hold thermal cut-outs are similar to auto-reset types except that they are fitted with an internal heating resistor.  Once the SO limiter reaches its set-point, the contacts open and the load current then passes through this internal heater.  The heat thus generated stops the SO bimetal disc from auto-resetting and protects the appliance from over-heating.

The SO cut-out will then remain in this open-circuit condition until the applied power is switched off and is allowed to cool down.  The SO will then auto-reset thus re-making the electrical circuit.  Basically the SO self-hold has the benefits of both auto-reset and manual-reset cut-outs without the limitations of either.

The SO is also available with various terminal types, numerous mounting flanges and calibrations from -5°C to +200°C.  The internal heater can be chosen to work with voltages from 12V to 240V which makes the SO self-hold device a very flexible thermal protector.