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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