Connect 12-Volt Positive from Power Supply to the COM (Common) port on the back of the R20.

Connect Positive Wire from the Maglock to the NC

(Normally Closed) port.

Connect both Negative (Ground) wires together from the Maglock and Power Supply.

For Exit Button:

Connect the NO (Normally Open) wire to the Door A input port.

Connect the COM (Common) wire to the GND port.

(Note: The Input must be enabled in the web interface for R20A.)