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1.01 PowerLift™ Winch: A. General 1. The winch shall be of a compact design with all required components integrated into its structure. It shall incorporate a structural backbone with adjustable steel mounting clips to facilitate horizontal or vertical mounting. The drum shall move along its axis as it rotates in such a manner that there is a zero degree fleet angle between the cable takeoff points on the drum and the head block sheaves incorporated in the winch. 2. All components shall be designed to properly support the required loads. 3. Characteristics: The winch shall have the following characteristics: Product Code 018-P0220F Speed (fpm) 20 Capacity (lb) 2000 Lift Lines 7 Travel 70’ 018-P1208V 018-P1220V 0 - 120 0 - 120 775 2000 7 7 70’ 70’ 018-P1809V 018-P1813V 018-P1820V 0 - 180 0 - 180 0 - 180 875 1275 2000 7 7 7 70’ 70’ 70’ B. Gearmotor and Brake: 1. The motor, primary brake and gearbox shall be an integrated unit. For enhanced reliability a continuous shaft shall carry the brake, motor armature and the first stage pinion gear without the use of couplings. 2. Motors shall be totally enclosed fan cooled (TEFC) per NEMA MG1. 3. The gear reducer shall employ helical gearing. The gear case shall be cast iron for protection against shock damage. The output shaft shall have triple lip oil seals to prevent leaks. The gear motor shall have a minimum service factor of 1.0. 4. Brakes shall be spring applied, direct acting, electrically released, and equipped with a manual release. The brake shall be an electro-magnetic unit with a minimum retarding torque equal to 200% of motor full load torque. The brake shall be released by energizing the coil simultaneously with the motor winding to provide fail-safe breaking in case of power failure. C. Drum & Sheaves 1. The drum shall be helically grooved to accept a single layer of cable accommodating the entire travel distance plus three dead wraps per cable. 2. Cables shall enter the drum through key slots and be retained by a Nicopress™ stop sleeve. 3. Chase rollers shall be provided to keep lift lines in their grooves. 4. The pitch diameter of all drums and sheaves shall meet or exceed the wire rope manufacturer’s minimum recommended D/d ratio. Wire rope groove profiles shall meet the recommendations of the Wire Rope Technical Board. 1 5. 6. Sheaves shall be molded in Nylatron GS®, and shall have a 5” minimum pitch diameter with a groove for 3/16”. galvanized aircraft cable. The groove shall be deeper than the cable diameter for protection. The sheave shall be equipped with a 12 mm diameter machined steel shaft and two sealed, precision ball bearings. Loft blocks external to the winch shall have side plates of 12-gauge steel which shall fully enclose the sheave. Idlers shall be provided for ongoing lift lines. To minimize cable wear each cable shave have its own groove. Idlers with more than one wire rope in a groove are specifically forbidden. D. Load Brake: 1. A Weston type load control brake shall be located on the low speed output shaft of the gearbox or be directly fixed to the winch drum. This brake shall be self applied in a manner that prevents runaways and shock loads. E. Limit Switches 1. A total of four mechanically driven limit switches shall be provided for normal end of travel and over travel indication. Switches shall be positively driven. 2. Limit switches shall be set to match actual site conditions. Reliance on encoders for end of travel safety functions is not permitted. 3. Switches shall be wired in a normally closed, or other circuit, that stops motion in the even of a failure in the circuit. F. Motor Controllers: 1. For fire and electrical safety, motor controllers shall conform to the NEC, be built in accordance with UL Standard 508, and be “touch safe” per IEC 204-1 “Protection against direct contact” rules. 2. The controller shall be sized to match the winch motor horsepower. Overload and overcurrent protection shall conform to UL and NEC requirements, including accessibility. 3. Controllers shall be wired so that operation of the normal end of travel limit switches shall only allow movement away from the limit switch. 4. The E-stop and overtravel limit switches shall be part of a circuit which is separate from and redundant to the normal end of travel limit switches. Operation of an E-stop or overtravel limit switch shall directly disconnect power from the winch(es), applies the primary brake(s), and will not allow further movement in either direction. A spring return toggle switch shall be housed inside the controller cabinet to allow override of the overtravel limits for resetting purposes. 5. Variable speed controllers shall be solid state flux vector controllers designed for hoisting duty. The controller shall incorporate closed loop feedback using a solid state position encoder mounted on the motor shaft to identify the speed and position of motor shaft in order to provide the greatest accuracy and performance. Each controller shall incorporate a microprocessor to provide direct control of torque and shaft position. The controller shall provide an essentially infinite speed range, including the ability to produce full torque at zero speed. The use of open loop drives is prohibited. 6. Controllers shall provide under voltage, over voltage, instantaneous over current, overload, and phase loss protection. 2 G. Control Station: 1. Control stations shall be wall mounted NEMA 1 enclosures, containing a hold to operate (dead man) Up and Down pushbuttons for each winch. A key operated On / Off switch shall be provided. 2. A red, mushroom head emergency stop pushbutton shall be provided, which will disconnect power to the winch through a fail safe circuit. 3. Panel components (pushbuttons, key switches, switches, indicators, E-stop switches, and the like) shall be industrial grade. H. Installation supervision and commissioning of the motorized rigging system shall be performed by a factory authorized and trained technician. 1.02 SceneControl™ A. The SceneControl system shall be specifically designed for the control of theatrical rigging equipment. The control system shall be built from standard, off the shelf industrial grade Programmable Logic Controller (PLC) components, selected for long term, reliable operation under the conditions and environment at the site. “Home” computers are not acceptable for overhead motion control. B. Operations: 1. Manual Control: The system shall allow the selection of one to six motors for control, through the use of “AND” and “THRU” functions. Selected motors may be controlled directly using manual “GO UP” and “GO DOWN” controls, or they may be directed to target positions selected numerically with the on screen keyboard. 2. Cue Control: Motor speeds and target positions can be composed, stored, modified, and recalled in the form of cues. Each cue shall control up to six motors, each with an individual direction, speed, and target position. 3. Groups: Several motors may be grouped together for synchronized operation. When motors are placed in a group, the system shall only permit operation of the group as a whole, and shall not permit the individual operation of any of the motors forming the group (except for trimming functions). During group movement, the system shall track the positions of all of the motors in the group and shall make any required correction to keep the group synchronized. Should one or more motors fail to stay within the window of tolerance for grouped operation or reach its end of travel limit, the system shall automatically bring the entire group to a halt. 4. The system shall include password-protected access, with separate levels for user, supervisor, and setup functions. C. Operator Interface: 1. An industrial grade video touch screen shall be provided as the primary operator interface. A graphic user interface shall be provided for ease of operation. Displays shall include a winch controller allowing the selection of motors for direct control; cue creation and editing; a display of the current position and target position of each winch or group. A winch status display shall allow the user to review the status of each winch including limit switch actuation, running hours, and fault indications. 3 2. Two cue controllers shall be provided, each with a compact industrial joystick and pushbuttons. Joysticks shall provide velocity adjustment of movements in progress. All direct control of motion shall be through joysticks and illuminated pushbuttons. The touch screen shall not be used to initiate or stop motion to prevent inadvertent initiation of movement. 3. “Deadman” operation is required, so that the operator must be at the console and pressing a button for motion to continue. Systems that allow motion to occur with no operator presence are prohibited. 4. a mushroom head “EMERGENCY STOP” button and a “ON/OFF” key operated switch shall be provided on the control console. 5. The console shall be height adjustable. D. All hardware components shall be industrial grade equipment designed for use in a typical theatre environment. All control modules shall be standard, off the shelf products of Mitsubishi Electric, Siemens, Allen Bradley, or other approved PLC manufacturer. These modules shall be widely available on an international basis to ensure ease of replacement and maintenance. 4