Model MJ
Medium-Duty
Jackshaft Operator

Standard Features:

• Motor:
  Powerful 1/2 HP, 115V single phase motor with reverse and internal automatic reset thermal overload. Removable without affecting limit switch settings.

• Operator/Motor Control:
  Dependable dual relay system (NEMA 1 enclosure).

• 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. 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 and third #48 chain.

• Pushbutton Station:
  3-button station for OPEN/CLOSE/STOP functions is standard for all operators.  Controls with one, two and three buttons are available.

• Construction:
  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.

• External Radio Control Terminal:
  External terminals provide quick, convenient connections for universal radio controls.

• Friction Clutch:
  Adjustable friction clutch helps protect against damage to the door and operator should the door meet an obstruction.

Clearance and Mounting Details

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