When using Detection Systems Multiplex Devices to a D8125MUX on D7000/D9000/G Series Panels, there are two series of devices: "i" and "non-i" devices (for example, DS7465 vs. DS7465i). The "i" devices are addressed with DIP switches; the others are not.
The non-DIP switch versions are programmed with a programmer and retain their addresses using a chip on the board. Addresses of these devices are changed by applying a voltage spike in the MUX bus, which is why the diode is installed on non-i devices. Devices that are addressed with DIP switches do not require the diode.
