The SmaRT DIN-9H4R-2DI Base Unit for industrial control systems features four Form A relay outputs. Each Form A relay is rated at 2 A max @ 250 VAC/30 VDC inductive load and 5 A resistive load. The unit also features two active high discrete input channels and two serial communication ports:

RS-232 Port – Update configuration and application code through this port.

CAN Port – Transfers handheld and base unit status to other nodes on the network, as well as optional bus termination.