Shorted Relay Alarm Board

A major concern when using solid state relays is the possibility of a shorted relay. Watlow’s “Shorted SSR Alarm” is a cost effective method of monitoring the output current to the heater and the control signal of the relay. The shorted ssr alarm will activate an alarm condition if there is no control signal detected while there is current to the heater. The alarm contacts can be wired to an audible or visual device to show an active alarm state or to the normally closed circuit of a latching relay to remove power to the heater. However, this alarm device is not a substitute for an agency approved over temperature limit control or safety device. Limit and safety devices must have a positive mechanical break of all electrically hot legs simultaneously.

NOTE: In all cases where uncontrolled full power can cause damage, it is recommended that a high limit temperature controller and contactor be used for protection.