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If using an external power supply, connect the ground (-) of the external supply to the ground (-) of the ACU’s main power supply
Note: Openpath recommends that you use the “GND for INPUTS” on the I/O Elevator Board only if all input devices use the same voltage
Connect one side of the input device (e.g. the C contact of the input device for an SPDT device) to the power supply
Connect the NO contact other side of the input device (e.g. the NO or NC contact) to an available input on the I/O Elevator Board
Repeat steps 2-3 for all input devices in use
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