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If you plan on using the ButterflyMX Card Reader for access (without an Openpath Smart Reader), run the W0, W1 and GND signals from the ButterflyMX to a Wiegand input on the 4-Door Controller or any I/O pair on the 4-Port, 8-Port, or 16 I/O Elevator Board. The ButterflyMX power supply and the ACU power supply should share a common ground. See How to wire Wiegand devices to Core Series hardware.
If you are installing an Openpath Smart Reader at the same entry as the ButterflyMX, connect the Wiegand W0 and W1 signals from the ButterflyMX directly to the WD0 (Green) and WD1 (White) wires on the Smart Reader pigtail.
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