The GT Model industrial type heavy duty worm gear trolley operator is designed to be used for rapid high frequency operation or on large standard lift overhead doors where no sideroom is available.
Three Button Control:
Momentary contact type for up, down, stop. Operator may be stopped in any position and door moved up or down from that position. Down button can be wired for constant pressure when specified. Control circuit 24V AC for users protection.
Adjustable Automatic Friction Clutch:
Will protect door and operator in case of obstruction (optional at extra cost).
Limit Switches:
Rotary type with oilite bronze cams and precision micro switches for automatic stopping of door in up and down positions (easily adjustable without tools).
Reversing Contactor:
Heavy duty type.
Reduction:
Worm gear reducer, single stage, running in an oil bath, 40:1 ratio, C flange design, alloy cast iron housing; door speed 8″ (20cm) per second approx.
Dual Trolley:
cast aluminium alloy chain driven carriage, slides in dual heavy steel angle tracks, with full No. 40 push and pull roller chain, for smooth and quiet operation. In addition a roller spreader is provided to support trolley and prevent chain from rubbing.
Quick Release Door Arm:
Quickly disengages operator from door at floor level (without tools) for manual operation in the event of power failure.
Motor:
3/4 HP (559.5W), 1 HP (746W), 1-1/2 HP (1119W), 2 HP (1492W) 120V or 240V single phase, 208V, 230V, 416V, 460V or 600V three phase. 2 Hp (1492W) not recommended on single phase motors.
Manual Overload Relay:
For overcurrent and under voltage protection (can be reset manually).
Headroom Required:
2-1/2″ (6.25cm) minimum from door’s highest arc of travel.
Backroom:
5’0″ (152cm) plus door height.
Finish:
Primed with rust-proof primer and spray painted in blue hammertone enamel.
Control Post:
Three push buttons, fully protected against any accidental push, allow the engine to start in the opening or closing direction, and also to stop it with a simple momentary touch of a finger. They are designed for normal use, enclosed in a non-watertight box, and can withstand a maximum voltage of 600 volts AC. The connection terminals are of the screw type.
Starter:
A robust type of switch, composed of two tripolar relays, each actuated by a hinge type armature with three suspension points and mounted on a common frame. A mechanical interlock prevents any simultaneous operation. Each relay is equipped with auxiliary contacts (single or double pole depending on needs) and its coil is powered at 24V AC. The load contacts are capable of cutting a non-inductive load of 15A @ 120V AC, 10A @ 240V AC, and 5A @ 600V AC. The connection terminals are of the “Quick Connect” type (0.25″ – 6.35mm). The service life of the mechanical parts is 10 million operations.
Control:
The components are enclosed in a pressed box made of steel plate according to EEMAC and C.S.A. type 1 standards. The box is equipped with a removable lid for easy maintenance. Its dimensions are 8″ X 16″ X 15″ (20cm x 41cm x 12.5cm) and it is attached to the operator’s frame with four galvanized steel bolts. The internal connections are made in the factory.
Limit Switches:
System composed of two “oilite” antifriction bronze cams with notches that are retained and guided by a stop bar made of galvanized steel plate, which is held under the tension of two springs. The cams move on a steel shaft (5/8″ D. x 10-3/4″ L. – 1.56cm D. x 26.88cm L.) threaded (N.F.) which rotates in a pair of pre-lubricated ball bearings. The cams, when they reach the positions chosen in advance during their adjustment, activate one or the other of the switches to stop the operator in the fully open or closed position. The switches require a maximum push of 4 oz. (113.3g). The spacing between their contacts is 0.020″ (0.5mm) and their connection terminals are of the “Quick Connect” type of 0.25″ (6.35mm).
Reduction:
The single-stage worm gear speed reducer (40:1 ratio) is composed of a hardened and ground steel screw that drives a bronze alloy gear; the input and output shafts, which are also hardened and ground, rotate in tapered roller bearings and are bathed in oil. The spaces between the cast alloy housing and the shafts are sealed by double contact seals that are held in place by springs and keep the oil inside and dirt outside. Maximum input power of 2 HP at 1725 rpm – maximum output torque of 1380 in/lbs at 44 rpm – maximum radial load on output shaft (1″ D.) 1100lbs. The door speed is about 8″ (20cm) per second.
Motor Unit:
The very robust frame of this unit is made of hot rolled steel angles (2″ x 2″ x 1/8″ – 5cm x 5cm x 0.31cm) and steel plate gussets. The whole is assembled by electric welding to achieve maximum rigidity.
Overhead Carrier:
Composed of two parallel hot-rolled steel angles (2″ x 2″ x 1/8″ – 5cm x 5cm x 3.1cm) mounted with hot rolled steel rods (3/8″ – 9.5mm). The cast aluminum alloy trolley is driven in both directions by a No.40 roller chain in a closed loop for smooth, frictionless operation. In addition, a spacer rotating on ball bearings supports the carrier in the center and prevents the chain from rubbing.
Safety Lever:
Hot rolled steel bar 1″ x 3/8″ (25mm x 9.3mm) – bent at 90 degrees – adjustable according to clear height. One end is attached to the trolley by a spring hook and the other to the door by an aluminum bracket. This lever allows the door to be disengaged (from the ground and without a tool) in the event of a power failure.
Disc Brake:
Comprised of a cast aluminum caliper, two “D” shaped friction pads, and a 4″ D. steel disc freely mounted on the input shaft of the speed reducer.
Adjustable Automatic Friction Transmission:
A non-combustible fiber disk is compressed by a strong spring and a self-locking nut between an aluminum disk with a diameter of 4″ (10cm) and a thickness of 1/8″ (0.31cm), which is pinned to the output shaft, and a No. 50B23 toothed wheel, which can exert a driving force of up to 200 pounds. This transmission can be easily adjusted according to the size and weight of the door and serves to protect both the operator and the door if it encounters an obstacle. The transmission slippage never disturbs the timing of the limit switches. The transmission is optional (at an additional cost).
Manual Thermal Protector:
Serves to protect the motor from current overloads or voltage drops. It is manually reset.
Command Transformer:
The control circuit is powered by a down transformer with a power of 25 volt-amperes. The primary voltage is either 120, 208, 230, 240, 416, 460, or 600 volts AC, and the secondary is always 24 volts AC.
Motors:
The motors used in these operators are of the “squirrel cage” type and designed for continuous use. They are offered in the following power levels: 3/4 HP (559.5W), 1 HP (746W), 1-1/2 HP (1119W), and 2 HP (1492W) and can be powered at 120V. or 240V. AC single phase (capacitor start) or 208V., 230V., 416V., 460V., or 600V. AC three-phase. Their loaded rotation speed is 1725 rpm, they run on ball bearings lubricated for life and are mounted in an open frame (EEMAC I). The shaft diameter is 5/8″ (1.56cm) or 7/8″ (2.22cm) depending on the power. Special windings for other voltages available on request. These motors are approved by C.S.A. The use of the 2 HP motor on a single-phase network is not recommended.
All internal electrical connections are made in the factory according to a standardized color code. The wires for external connections are labeled to indicate their functions. A connection diagram is provided with each machine and each is load tested in the factory before shipping.
Leader in door and gate operator
