SUPPLY POWERMASTER MODEL “MJ” MEDIUM DUTY JACKSHAFT OPERATOR(S) RATED 1/2 HP, 115 VOLTS, SINGLE PHASE, FOR USE ON STANDARD LIFT SECTIONAL DOORS, ROLLING DOORS AND GRILLES UP TO 14’ HIGH. MOTOR SHALL BE INSTANTLY REVERSIBLE, PERMANENT SPLIT CAPACITOR TYPE, PROTECTED FROM OVERLOAD BY A CURRENT SENSING OR THERMAL TYPE OVERLOAD DEVICE. PRIMARY SPEED REDUCTION SHALL BE BY MEANS OF AN INDUSTRIAL DUTY V BELT. FINAL DRIVE SHALL CONSIST OF HEAVY DUTY ROLLER CHAIN AND SPROCKETS. AN ADJUSTABLE TORQUE LIMITING CLUTCH SHALL BE PROVIDED TO PREVENT OVERLOADING OF OPERATOR. ALL SHAFTS SHALL BE 1” DIAMETER STEEL AND SHALL BE SUPPORTED BY BRONZE BUSHINGS. THE REDUCTION MECHANISM SHALL BE SELF LOCKING ELIMINATING THE NEED FOR A BRAKE.
CONTROL OF THE OPERATOR SHALL BE BY A CLASS II, 24 VOLT POWERED CIRCUIT, CONSISTING OF SOLID STATE CONTROL BOARD, TRANSFORMER AND LIMIT SWITCHES. ALL COMPONENTS OF CONTROL SYSTEM SHALL BE UL RECOGNIZED. ELECTRICAL COMPONENTS SHALL BE INSTALLED IN A NEMA 1 ENCLOSURE. A TRANSFORMER SHALL BE PROVIDED TO REDUCE CONTROL VOLTAGE TO 24 VAC MAXIMUM. TERMINAL STRIPS SHALL BE PROVIDED FOR CONNECTION OF POWER SUPPLY LINE AND ALL CONTROL DEVICES. OPERATOR SHALL BE WIRED FOR CONNECTION OF A RADIO CONTROL, PUSH BUTTON STATION AND AN OBSTRUCTION SENSING DEVICE WITHOUT ADDITIONAL WIRING MODIFICATIONS. CONTROL CIRCUIT SHALL PROVIDE INSTANT REVERSE MOTOR WIRING. POSITIVE CHAIN DRIVEN, ROTARY TYPE LIMIT SWITCHES SHALL BE PROVIDED TO LIMIT FULL OPEN AND CLOSE TRAVEL OF DOOR. LIMIT SWITCHES SHALL NOT BE AFFECTED BY REMOVAL OF MOTOR OR BY MANUAL OPERATION OF DOOR.
