A device that meets every requirement of OSHA regulation 1910.217b(14) for mechanical power presses. Features microprocessor-based electronics, 3-digit LED display for stop or reserve (time to alarm) times, auto-learn mode, continuous self-check circuitry, chain break monitor, and enhanced relay protection (includes welded contact detection).

The DM3000 Brake Monitor system components are: a control unit and a motion detector (standard with 10' cable - other lengths available upon request).

The control unit interfaces electrically with the motion detector, by means of a motion detector cable. The motion detector is mechanically connected to the crankshaft of the press by chain, belt or direct drive and generates an electrical signal whenever there is shaft movement.

The brake solenoid voltage (which is removed to apply the brake on the press) is constantly monitored by the control unit. When the voltage is removed, a high precision digital counter is activated, which continues to count until the motion detector signal indicates all motion has ceased. The elapsed time is indicated on a 3-digit LED display on the face of the control unit.

The Brake Monitor opens the control relay in the Stop Output circuit, whenever the stop time of the press exceeds the preset limit - the Stop Output must be wired in a way that prevents a successive stroke of the press. The Stop Output also features a safety relay with its contacts wired in series with those of the control relay. This safety relay works in conjunction with an armature configuration in the control relay, which allows for the detection of a welded relay contact, and opens the Stop Output if a contact weld occurs. A separate, adjustable Warning Output provides a means to alert personnel to the fact that stop times are approaching the alarm point - this feature warns of brake wear and helps to eliminate unintended machine stops.

The combination of a key lock and keypad allows the authorized user to alter the alarm, warning and chain-break delay settings and to control whether the unit displays stop or reserve times. The key lock enables the keypad access. An access code prevents unauthorized keypad entry.

A self-check circuit monitors the control. It operates continuously and is independent of machine cycle. In the event of a self-check fault, the Stop Output opens and a fault code is displayed on the 3-digit LED. A chain-break detection circuit monitors the motion detector input and alarms the unit if the motion detector is either disconnected or fails to provide a signal.