The MMTC 4-20-3 Coil Cord is a four-conductor coiled cable used to connect moving door or gate components—such as a sensing edge on a rolling steel or sectional overhead door—to the fixed control panel or junction box. Designed for commercial and industrial door operator systems, this flexible cord maintains a reliable electrical connection through the full travel of the door or gate, making it a practical replacement part for worn or damaged cords in safety edge and control circuit applications. Its 4-wire configuration supports many monitored and non-monitored safety edge setups and other low-voltage accessories commonly found on gate operators and commercial overhead door systems.
Based on the model designation, the 4-20-3 provides four conductors with an approximate 20-foot working extended length and about 3 feet when relaxed, offering ample reach for typical door travel while minimizing excess slack. It is intended for low-voltage control circuits used in door and gate operator accessories. Installation generally involves terminating the color-coded leads to the sensing edge or moving device at one end and to the operator or junction box at the other, ensuring proper strain relief, routing away from pinch points, and avoiding overextension beyond the rated travel. After wiring, power should be restored and the system tested—particularly obstruction reversal functions per UL 325 practices—before returning the door or gate to service. The MMTC 4-20-3 Coil Cord is widely compatible across many brands that require a 4-conductor coil cord for safety edges and similar controls in residential/commercial applications.