ACU3 Antenna Changeover Unit – operating modes:
The unit can operate in different modes. Mode selection is done with the DIP switch located on the board inside the unit.
There are two distinct modes of operation, one is key controlled, and the second is alarm controlled. In key controlled mode, the ACU will select the transmitter that is keyed and stay on that transmitter until the other transmitter is keyed. The other main mode is Alarm controlled. In this mode the ACU3 relay is controlled by the alarm state of the transmitters. Each mode has different options that can be enabled or disabled.