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LiftMaster MJ electric garage door opener

MJ

Features

The MJ model is a medium-duty door opener, as manufactured by The Chamberlain Group and is for use on vertical or high lift sectional doors or small rolling doors and grilles. It is rated for 12 cycles per hour during peak periods. Up to 50 cycles/day

Single phase: 115 V
Horsepower: ½ HP
Minimum side room required: 18 in (457 mm)
Solid‑state medium‑duty logic circuit board.
High‑starting torque operator with instant reverse.
Capacitor start on single‑phase
NEMA 1 type electrical box, heavy‑duty 11‑gauge steel frame with baked‑on powder coat finish, all reduction sprockets drilled and pinned to shafts.

Motor is removable without affecting limit switch settings.
Heavy‑duty solenoid brake
First‑stage heavy‑duty 4L V-Belt; second and third stages #48 chain
Heavy‑duty oil‑filled bushings.
Adjustable friction clutch helps protect against damage to the door and opener should the door meet an obstruction
Provides emergency manual operation using an electrically interlocked floor level disconnect

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
UL and CSA listed
2‑year warranty
NOT compatible with myQ

Standard security systems

Your security, our priority!

Security+^®

The MJ is equipped with a Security+ rolling code receiver. With every activation, Security+^®transmits a brand-new code, one of over 100-billion codes, never to be repeated.

CPS^® commercial protector system^®

CPS‑U photo eyes are shipped with unit. They project an invisible light beam across the garage door opening and automatically reverse the door if anything interrupts the beam while the door is going down. Sensing technology will stop the door from closing if contact is made with a person or object. Alternate entrapment protection devices may be used or added, such as light curtains and optical edge systems.

Warning

Garage doors and garage door openers can be dangerous if not installed and verified by a professional and not used properly. Children must be supervised by an adult when they are inside or in proximity of the garage.

Security+^®

The MJ is equipped with a Security+ rolling code receiver. With every activation, Security+^®transmits a brand-new code, one of over 100-billion codes, never to be repeated.

CPS^®Commercial protector system^®

The presence of primary entrapment protection is standard CPS‑U for all modes. Primary entrapment protection devices are monitored continuously to ensure safe operation of the door and limit door opener functionality should an obstruction be detected or in the event of device failure. Optional LiftMaster Monitored Entrapment Protection devices, CPS‑UN4, CPS‑RPEN4 and CPS‑EI, are designed to work in conjunction with LiftMaster commercial door openers 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.

Warning