LiftMaster MH Medium-Duty Logic Jackshaft Operator is a commercial-grade door operator designed for smaller and lighter rolling steel doors, grilles, and high or vertical-lift sectional overhead doors with mid-range duty cycle requirements.

This operator is engineered for medium-duty commercial applications, supporting up to 12 cycles per hour and up to 50 cycles per day. It features a wall-mounted jackshaft design and integrated chain hoist with electric interlock, allowing safe manual operation during power outages or emergencies.

The MH series is equipped with LiftMaster’s medium-duty logic control board, programmable timer-to-close functionality, and solid-state electronics, delivering reliable performance in commercial and industrial environments.

Key Features

• Medium-duty commercial jackshaft operator

• Suitable for rolling steel doors, grilles, and high or vertical-lift sectional doors

• Rated duty cycle: up to 12 cycles per hour / up to 50 cycles per day

• Operator speed: 8–9 inches per second

• Mechanical limit settings

• Floor-level emergency release sash chain

• Auto-reconnect emergency disconnect

• Programmable timer-to-close (5–60 seconds in 5-second increments)

• Adjustable friction clutch

• 3-button control station (Open / Close / Stop)

Specifications

Radio Receiver

• Security+R 315 MHz radio receiver

• Supports up to 23 Security+ remote controls • Unlimited DIP switch remote controls 

Electrical

• Single-phase: 115V

• Control circuit: 24V NEC Class 2

Drive System

• First stage: Heavy-duty 4L V-belt

• Second and third stages: #48 chain

• Heavy-duty oil-filled bushings 

Brake

• Heavy-duty solenoid-actuated brake 

Construction

• NEMA 1 electrical enclosure

• Heavy-duty 11-gauge steel frame

• Baked-on powder-coat finish

• Drilled and pinned reduction sprockets

Warranty

• Limited warranty: 2 years 

Installation Features

• Universal mounting: Yes

• Maximum door height: 14 ft standard (additional capability available)

• Maximum door width: 22 ft

• Maximum allowable door area: 320 sq. ft. 

Download PDF

Price available upon request. Contact us for a custom quote.