We have recently become aware of a feature of Dover Elevator Controllers Model DMC-1 that can confuse elevator technicians when connecting field wires in controllers during construction or making repairs or replacements. If field wiring (door contact/control circuits) is connected to the "XI 1" terminal on the incorrect terminal block, the system for protection against faulty door contact circuits required by B44-94 Clause 3.12.1.5. is BYPASSED.

Dover supplies 2 terminal studs labeled "XI 1" located on two different terminal blocks. The terminal blocks and the two "XI 1" studs serve different functions.

Correct Field Wiring Connection

Field wiring must be connected to terminal stud "XI 1"[T22-5]. (on Terminal Block 22; Pin 5).

Wrong Field Wiring Connection

If the field wires are connected to terminal stud "XI 1"[T15 - 2] (on Terminal Block 15; Pin 2) the system for protection against faulty door contact circuits will be bypassed.

CHECK THE LOCATION OF FIELD WIRING AND ENSURE THE DOOR CONTACT MONITORING SYSTEM FUNCTIONS AS PER CODE REQUIREMENTS.

Reference (below) portion of the controller wiring schematic involved.