Abstract: A monitor system for use with a plurality of segregated groups of controls, each group having corresponding status control lines indicative of the operational status of an elevator, an escalator, or the like. The monitor system includes a series of monitor devices for responding to the status control lines. Each one of the monitor devices corresponds to an individual one of the group of controls, for diagnosing the operational problems associated therewith. A computing device is located remotely from the groups of controls, for monitoring them remotely and continuously. A plurality of individual single communication links correspond individually to one of the monitor devices, for facilitating connection selectively and individually of the monitor devices to the remote computing device.