Model MJ is a Medium Duty Logic jackshaft operator. It features a compact design, an adjustable friction clutch, a standard solenoid brake and a high-starting torque motor.
Medium-Duty Logic Technology
- UL325-2010 compliant Medium-Duty Logic programmable integrated circuit board
- Built-in 3-channel, 315MHz radio receiver accepts up to 20 Chamberlain® Security+® or unlimited DIP switch remotes. 3-button remotes can be programmed for OPEN/CLOSE/STOP operation
- Programmable C2 or B2 wiring options (B2 requires CPS-U, CPS-UN4, or CPS-EI)
- Integrated timer-to-close (TTC) allows programming from 5 to 60 seconds in 5-second increments. Allows for timed automatic door closure after the door reaches the full open position (Requires monitored safety devices, with CPS-U, CPS-UN4, or CPS-EI)
- Integrated 90-second maximum run timer
- UL325-2010 Monitored Entrapment capability
- Monitored protection against transient overvoltage conditions
- 3-button control station included
Motor: Powerful 1/2 HP, 115V single phase motor with instant reverse and internal automatic reset thermal overload. Removable without affecting limit switch settings.
Operator/Motor Control: Solid-state Medium-Duty circuit board.
Control Circuit: 24V NEC Class 2.
Floor Level Disconnect: Floor level disconnect provides emergency manual operation.
Brake: Heavy-duty solenoid actuated brake standard.
Wiring Type: All operators are factory preset to C2 wiring providing momentary contact to open and stop with constant contact to close. Momentary contact to close (B2 wiring) can be easily set, but requires the presence of either CPS-U, CPS-UN4, or CPS-EI safety devices. The operator is pre-wired to accept a sensing device, photoelectric control, radio controls and most types of access control equipment.
Drive Reduction: First stage heavy-duty 4L V-belt; second stage and third stages #48 chain.
Push Button Station: 3-button station for OPEN/CLOSE/STOP functions is standard for all operators. Controls with 1, 2 and 3 buttons are available.
Construction: NEMA 1 Type electrical box, heavy-duty 11-gauge steel frame with durable baked-on powder coat finish, all reduction sprockets drilled and pinned to shafts.
Friction Clutch: Adjustable friction clutch helps protect against major damage to door and operator should the door meet an obstruction.
Radio Receiver: 315MHz radio receiver is integral to the Medium-Duty logic board. Accepts up to 20 Security+® remote controls and unlimited DIP switch remote controls.
Warranty: 2-year warranty.
Control Accessories and Options
Primary Monitored Entrapment Protection: The presence of primary entrapment protection is required for all modes and features beyond basic constant-pressure-to-close performance. Primary entrapment protection devices are monitored continuously to insure safe operation of the door and limit door operator functionality should an obstruction be detected or in the event of device failure. LiftMaster Monitored Entrapment Protection devices, CPS-U, CPS-UN4 and CPS-EI, are designed to work in conjunction with LiftMaster commercial door operators to provide enhanced door safety and a broad range of modes and features to end users. Either monitored photo-sensor or monitored 4-wire sensing edge (in conjunction with the CPS-EI Edge Interface) protection may be selected, but one must be detected by the LiftMaster Logic 4.0 or Medium-Duty Logic circuit board in order to unlock full functionality.
Ancillary Entrapment Protection: (optional) LiftMaster Retro-Reflective Commercial Protector System® photo sensors, 2-wire non-monitored sensing edges and pneumatic sensing edges are considered secondary entrapment protection and may be used to supplement primary entrapment protction or basic constant-pressure-to-close.
Emergency Egress Device: Faceplate mounts flush on wall and contains pull handle to disconnect operator from grille. Allows the door to be opened manually or by spring tension.
Rolling Door Interlock Switch: Interlock switch disables the operator control circuit when a manual door lock is engaged preventing damage to the door and operator.