Model GT STANDARD FEATURES

 Model Specific: Work included – The electric operator will be Lift-Master Model GT as manufactured by The Chamberlain Group, Inc. Related work – Door preparation, miscellaneous or structural metal work, field electrical wiring, wire, conduit, fuses and disconnect switches are in the scope of work of other divisions or trades. 

Product: Supply Model GT, heavy industrial-duty, cUL listed, gearhead trolley operator(s) rated ___H.P., ___Volts, ___ Phase. 

General: Provide cUL listed electric door operator assembly of size and capacity recommended by door manufacturer; complete with electric motor and factory-prewired motor controls, 3-button open/close/stop control station, conduit and wiring from control to motor and accessories required for proper operation. 

Electric Motor: Motor shall be high starting torque, continuous-duty, industrial type, protected against overload by a current sensing or thermal overload device. 

Motor Starter, Controls, Enclosures: Option #1: For 115V (1/2 through 1 H.P.), 208-240V (1/2 through 2 H.P.), 460V (1/2 through 1-1/2 H.P.): Motor Control, Control Stations, Enclosures: Motor control shall be cUL approved microprocessor solid state type, and include a maximum run timer for motor protec-tion. Motor control device shall be enclosed in a NEMA 1 enclosure and integral with the oper-ator. Control enclosures shall conform to ANSI/NEMA ICS6. Open/close/stop station shall be NEMA type 1, and shall incorporate a mainte-nance alert indicator to signal intervals for routine door and operator maintenance. Special Note To Architect: For cUL approved Self-Monitoring Safety Operation in 115V and 208-240V single or three phase applica-tions, select Option #1 and add “Must include a CPS II™ Self-Monitoring Sensor to detect obstructions in the doorway.” Option #2: For 115V, 208-240V, 460V or 575V operation: Motor Starter, Controls, Enclosures: Motor starter shall be an across-the-line, mechanically interlocked, magnetic reversing contactor. Motor starting device shall be enclosed in a NEMA 1 enclosure and integral with the operator. Control enclosures shall conform to ANSI/NEMA ICS6. A NEMA type 1 open/close/stop control station shall be provided as standard equipment. 

Frame and Reduction: Primary speed reduction shall be wormgear-in-oil-bath gear reducer and #41 chain and sprocket secondary. All reduction sprockets and pulley shall be drilled and pinned to steel shafts. All shafts shall be plated for resistance to corrosion. Operator shall be equipped with an adjustable torque limiter, quick disconnect door arm for manual door operation and permanently lubri-cated ball bearings on the output shaft. The track shall be 11-gauge, heavy-duty, double angle galvanized steel. Door drive shall be #41 roller chain and a solenoid brake shall be supplied. Operator shall be capable of driving the door at a speed of approximately 11 to 12 inches per second. 

Limit Switches: Fully adjustable, driven linear type limit switch mechanism shall synchronize the operator with the door. Low friction nylon limit nuts fitted on threaded steel shaft, rotating on oilite self-lubri-cating bronze bushings. The motor shall be removable without affecting the limit switch settings. 

Trolley Assembly: 2" x 2" galvanized steel angle rails with cast aluminum trolley. Plated steel rail spacers with nylon chain-guide assembly. Execution: Install the motor operator in accordance with Lift-Master instructions and standards and in compliance with applicable federal, state or local regulations. 

Warranty: Lift-Master Commercial Door Operators and accessories shall be warranted to be free of any defect in materials and workmanship for a period of two years.