Where should resistors on a supervised line be placed?

In supervised alarm circuits, resistors are placed at the end of the line (EOL) to monitor the circuit's integrity. This setup helps detect any tampering, open or short circuits, or line interruptions. If the resistor is not at the end, it defeats the supervision purpose, as the system cannot verify whether the line is intact all the way to the device.

Placing resistors before or after each device is unnecessary and could create false readings.

Placing it in the control panel (D) bypasses the wiring run altogether, which defeats the supervision function.