Detection circuit and system for detecting detector removal failure

A detection circuit for detecting a detector removal fault, characterized in that the detection circuit being provided in an area monitoring module, the area monitoring module being coupled with a terminal resistor via a plurality of diode bases cascaded to each other for mounting a detector, the detection circuit comprising:

• a switching circuit, the switching circuit comprising one or more switching elements;
• an energy storage element;
• and
• a control circuit for controlling the energy storage element to discharge by controlling the one or more switching elements in the switching circuit to perform an opening or closing action;
• wherein the control circuit is configured to cause the energy storage element to discharge based on a first loop if the detector is removed from the diode bases, and to cause the energy storage element to discharge based on the first loop and a second loop including the terminal resistor if the detector is not removed from the diode bases, and
• wherein the control circuit is further configured to detect the detector removal fault based on an output voltage of the area monitoring module during discharge process.