The PRA-725 relay actuator and isolated D/I card provides eight electromechanical SPDT relays and eight optically-isolated digital inputs on a half-size card. Its eight on-board SPDT relays are ideal for applications such as device On/Off control or low power switching. A red LED next to each relay shows its On/Off status for easy monitoring. The PRA-725抯 eight optically-isolated D/I channels are ideal for digital input in noisy environments or with floating potentials. You can configure each input channel individually for either isolated or non-isolated input by setting jumpers. An on-board DB-37 connector provides access to all input and output channels.