The 3950 DC Solid State Relay can be used to switch loads of up to 50A at 30VDC using the digital output from a Phidget I/O board. The Relay comes with an optional protective cover to protect people from touching the exposed high power wires, and a diode to protect your SSR from harmful transients. All wires connect to this relay by screw terminals. If you are switching a high power load or find the relay is getting hot, please consider a heat sink. Heat sinks 3955 and 3956 are designed for use with this relay.

Electrical Properties

Physical Properties

Other Properties

When choosing a SSR, check the actual load current and the working ambient temperature. Refer to the characteristic curve in the Data Sheet and select the proper heat sink if required. Use the heat transfer pad between the SSR and the heat sink. Failure to do so can cause overheating and could damage the relay. Make sure that the SSR terminal screws are tight. If the screws are not tight, the SSR will get damaged by heat generated when the power is ON. Check the Data Sheet for recommended tightened torque. When an SSR fails, it most often fails permanently closed - leaving your load powered, and possibly creating a fire or safety hazard. You can use a fuse to protect your circuit from wiring mistakes and accidental short-circuits. Make sure that you use the relay within the product specifications.