MI-MM3E micro monitor module provides an interface between the normally open contact alarm initiating devices. Though the module can be used to monitor an entire zone circuit, it is ideally suited for monitoring single devices. The module is small enough to fit inside a single-gang junction box behind the device being monitored. The small size and lightweight allow it to be installed without the need to be rigidly mounted. It is used to monitor a single device or a zone of 4-wire smoke detectors, manual call points or pull stations, waterflow devices or other normally open dry-contact devices. A 47K Ohm end-of-line resistor (provided) terminates the circuit. It responds to regular polls from the control panel and reports its type and the status (open/normal/ short) of its zone.