Duo Power Supply

The system is supplied with a 120 VAC plug. This plug may be cut off, and the existing three wires can be used to connect the system to a 240 VAC single-phase power supply.

When wired for 240 VAC single-phase, the unit uses two hot lines (L1 and L2) and a protective ground. A neutral conductor is not required for operation. 

Incoming AC power is converted to 24 VDC via an onboard power supply module.

The circuit board also includes a dedicated 24 VDC input. When using this configuration, the AC input must be disconnected and the system powered directly via the designated 24 VDC input terminals.

Refer to the figure below for details.