The 500 Series multiple input and output modules are designed to meet a range of applications in which numerous single modules are used. This design allows for installation ease and time savings. The monitor and control modules can be used to supervise and activate sounders, strobes, door closers, pull stations, water-flow switches, conventional smoke detectors and more. The conventional zone interface module is ideal for retrofit applications to monitor zones of conventional two-wire detectors. Each module has its own address. Modules are addressed with easy-to-use rotary code switches. Provisions are included for disabling unused addresses. Up to two modules mount in a BB-2 enclosure with built-in chassis and up to six modules mount in a BB-6 enclosure with the CH-6 chassis. Wiring terminals are easily accessible for trouble-shooting purposes. The IM-10 Ten Input Monitor module provides an interface between a control panel and normally open contact devices such as pull stations, security contacts, or flow switches. The first address is set from 01 to 90 and the remaining modules are automatically assigned to the next nine higher higher addresses. Provisions are included for disabling a maximum of two unused addresses. The supervised state (normal, open or short) of the monitored device is sent back to the panel.