Hoisting and winching equipment operates behind the scenes in entertainment industry applications, so the annual exhibition of the UK’s Professional Lighting and Sound Association (PLASA)is an opportunity for manufacturers to put their capabilities under the spotlight.
At their annual London show for entertainment and technology, PLASA members show lighting, sound systems and equipment to produce special effects. Lifting gear and its integration is a critical element of productions, events and architectural installations. Stage engineering companies and the rest of this year’s 350 exhibitors had 13,373 visitors, 25% of them from abroad, during the four days of PLASA 2001.
The PLASA organisation exists to promote the entertainment technology industry both in the UK and internationally. The programme includes a range of activities and awards. The prize for the best display stand up to 50m2 went to Tomcat, supplier of stage support systems including trussing, lifting and rigging equipment. The New Technology Gallery section of the show contained a record 56 new products nominated for the PLASA Product Awards for Excellence. Stage Engineering, one of the four award categories, had an entry from Verlinde with its new Stagemaker F hoist.
Making its debut at the show, Verlinde’s Stagemaker F Cyberhoist is claimed to be a revolution in rigging and motion control. Described as the first real intelligent hoist, it is the result of close cooperation with Dutch lighting specialist Flashlight.
Primary features include the controlled interaction between lighting and rigging and the claimed time saving when erecting a show, due to simple installation. Above all, Verlinde says, the accurately and smoothly variable speed control from real zero to 20m/min, allows programming to a precision of ±0.1mm over the full chain length, and a slow speed capability of 0.1mm/sec. Automatic speed adjustment, if travel distance or travel time has priority, is another feature as are load-controlled speeds.
Merging the closed loop flux-vector inverter and hoist-control software, Verlinde claims, gives a finely controlled hoisting motor that provides full torque from real zero to maximum speed, with low operating noise. It allows variable acceleration and deceleration over the full speed range as well as dynamic braking. The mechanical brake closes only after reaching a true and confirmed zero speed, according to the company.
Each Stagemaker F hoist has its own network identity and is designed and configured to work either stand-alone or in an Ethernet network with further units. Once connected to the network there is interaction between other connected units. Verlinde claims a major difference, however, in that a server is not required, unlike with multiple hoists linked on a traditional network.
A laptop or palmtop computer is sufficient to program and activate either a single F hoist or a group of them. Programming structures are the same as those commonly used for lighting desks. Cues are automatically stored in each hoist’s memory and up to eight cues can be active at the same time. Interaction with DMX or other Ethernet controlled equipment, such as winches, fly-booms, moving lamps and special effects is now a reality, Verlinde claims.
Verlinde export sales manager Mohamed Essabar says the next development is a three dimensional CAD-based system for using three hoists together to move an object in three dimensions.
Another entertainment industry speciality is using hoists and winches to ‘fly’ people. PCM, which incorporates Pfaff Silberblau and Pfaff Stage Technology, launched its Tau winch for aerial performances. Possibilities of the new cable winch system were demonstrated at the show by using three units to fly two performers above the stand in a display of aerial acrobatics.
The electric winch system has special CE certification for performer flying. Lifting capacity is 150kg, speed range is from 0m/sec to a high maximum of 5m/sec and maximum height of lift is 32m. A dual failsafe braking system allows performers to be lowered and rescued even if there is a power failure. Further safety features include four position limits mounted on the winch plus software limits, and overload and underload monitoring.
Tau’s computerised ‘real time’ joystick control in two and three dimensions, with bridles and tracks, is designed to provide maximum freedom of movement for the performers. Hitachi PLC with full closed loop inverter control gives repeatability and positional accuracy to better than 0.75mm, PCM claims.
A specially designed travelling rope guide and fleet angle eliminator with a roller to press the rope against the drum is used to ensure proper rope lay even at high speed or when the rope is only lightly loaded. The rope clamp design is to make the rope easy to install, inspect and replace. Extended rope life is a further claimed benefit achieved by preventing bending and kinking of the rope on the drum.
John Jones, managing director of PCM, sees the Tau as rental equipment rather than something that will be sold outright. Other products shown by PCM included the Delta winch for scenery movement and, as it is also a Columbus McKinnon distributor for the UK and Europe, a new version of the CM Prostar was shown along with several Lodestar hoists.
Launched on Columbus McKinnon’s own stand was the ShowPro hoist, part of what is billed as a complete plug and play electric hoist system. Capacities available include 0.5t, 1t and 2t, with lifting speeds of 4.1m/min, and 2m/min for the 2t SP4003 model on two chain falls. The ShowPro hoist, “designed to meet all basic rigging needs,” is a US-built stripped down version of a Coffing model UJL hoist. It has no onboard contactors or transformer and it has straight cut gears. The aluminium housing reduces weight and and the five pocket chain wheel reduces noise.
Prostar 500lb and 1,000lb (227kg to 454kg) electric chain hoists were also launched at the show.
Another new chain hoist, the Vario Lift BGV-D8, was among several products launched by Chainmaster Bühnentechnik from Germany. The BGV-D8 is 1t-rated and lifts at up to 19m/min.
Also new from Chainmaster was the Vario Trolley range for horizontal movement. Capacities of the trolleys are between 1t and 5t and the operating speed is variable up to 40m/min using a built in frequency inverter with path control and synchronisation. An integrated incremental encoder ensures exact positioning. The control unit also has an analogue input interface for a load cell, as well as a digital output interface for chain hoists. The Bus-controlled Vario Trolley is available for different Bus systems including CAN, Profibus, Interbus, Device Net, Ethernet, RS-485 and Light-Bus.
Chainmaster was also showing the Rigging Lift Pro II, claimed to be the world’s smallest and lightest 1t chain hoist with contactor control for the entertainment industry. A five pocket chain wheel and a plastic chain guide are designed to prevent chain jam and damage. Weight of the Pro II without chain is 28kg.
Vario Lift 1000 was also shown by Chainmaster. The company claims that this is “the world’s fastest and most precise chain hoist for the entertainment industry”. A built-in vector controlled frequency inverter gives variable speed from 1m/min to 19m/min. Programmable soft start/stop functions minimise the dynamic load, the company says. Two independent brakes are fitted for safety. An incremental encoder allows positioning accuracy to within 2mm, it is claimed. To comply with the German standard VBG 70 / BGV C1 for lifting over people, the Vario Lift 1000 is also available in a 500kg capacity version with a safety factor of 12.
Automated positioning control for chain hoists, with or without encoders, is the purpose of Outboard Electronics’ Ibex programmable hoist controller. Linked to the company’s hoist control modules Ibex produces easily programmed and repeatable hoist movements to an accuracy of ±2mm, the company claims. An Ibex system has recently been used on tour with pop singer Robbie Williams where it controlled the movement of stage lighting trusses.
Away from sophisticated electronically controlled lifting equipment, Loadtite Event Rigging Services showed a new 1t hand chainblock with a black chain and black paint finish to the body for camouflage. Also new is a range of black pin bow shackles. For rental and for sale the company supplies lifting, rigging and fall arrest equipment.