DC Powered SR controllers provide DC inputs and both relay and solid state outputs. The DC inputs may be treated as digital or analog (0-10 Vdc) inputs.

The Compact DC powered SR controller provides 12 I/O points: 8 inputs (6 may be treated as 0-10 Vdc analog) and 4 outputs.

The Standard DC powered SR controller provides 22 I/O points: 14 inputs (10 may be analog) and 8 outputs.

Up to 3 DC powered I/O expansion units may be added. Each expansion unit provides 12 digital inputs and 8 relay or solid state outputs. No analog  options are available on the I/O expansion units.

NOTE: It is not possible to mix AC and DC powered units. A DC powered expansion unit must be used with an DC powered controller.

DC Powered controllers are available with or without an LCD Graphics Human-Machine Interface (HMI) display/keypad.

The APB family of PLCs is UL508a compliant when used with Class II power. (Applicable to the DC units.) Slave UL508a compliant relays should be used when switching voltages greater than 48 Vdc.