Modular Wiring - Wired for play

The project was spawned from the promotion of standardisation in the Egan Report. The method was said to be an effective way to reduce costs and improve building performance through off-site prefabrication of parts. No more cutting and fixing on-site, simply final fix plug- and-play systems, which reduce waste and potential accidents while increasing productivity.

Paul Davies of Modular Wiring Systems describes the dream of modular wiring as: "A complete plug-in system for lighting, power, voice and data, control networks and risers." The company sponsored a university project which investigated how to improve speed and installation on lighting projects: "Cost was identified as a major factor and the biggest risk was found to be with labour, so off-site prefabrication was promoted," stated Davies, quoting 25-50% cost savings over traditional methods by using modular wiring.

The company's system is based on three main components: a lighting/power T; master distribution box; and extender cable. "It is not a new system and has been established in the uk for 5-6 years," assures Davies.

The parts are designed to remove confusion or error during installation, and the wrong ends will simply not fit together. Pre-wired junction boxes eliminate the need for trunking feeds to services and reduce the need for traditional forms of containment. "The system is suitable for a multitude of environments," states Davies, "including commercial offices, hospitals and industrial applications." Metway Net-Works' Marc Asker reiterates this point: "The key principles remain the same no matter what is required of the final system." Metway again uses a three component system, which "can't be connected wrongly".

The issue of standardisation between manufacturers' components is a big concern. Currently each manufacturer uses its own set of standard connections for its products and two different companies' products cannot be mixed. Which type of connection will end up as the preferred industry option is a major question. As one delegate questioned: "What if the system I choose doesn't become the standard, or the manufacturer goes bust?" Ken Bromley of the BRE concurred: "The issue has been especially raised on PFI projects, where the consortium is committing to a 25 year life. But the incompatibility still exists. BRE is hoping to start a research project on these issues and how to resolve them," he added.

Bill Wright of the John Lewis Partnership stressed that despite the company's enthusiasm for the products, it "has worries for the long-term...that parts will not be available in ten years. If modular wiring is going to take off there must be standardisation," he concluded.

The two types of wiring available are also causing confusion: "How do we know which to use?" despaired delegates, "The Regulations give guidance but don't specify the exact requirements of what has to be used where." The general conclusion involved the need for an independent body to set the standards: "If one manufacturer was to put forward a set of codes without an independent body being involved it would not be accepted," stated Metway's Marc Asker. Whether there is a role for the BRE remains undecided.

Contractors and clients accepting modular cabling may be the easy part of getting the system into widespread use. Project specifications are a big sticking point it seems. One m&e contractor expressed a desire to make more frequent use of modular wiring systems, but stated this was hampered by "specifications written years ago which don't take standardised systems into account". "Until consultants offer the contractor the option of using an alternative method, the industry won't change." The absence of consultants at the conference was attacked as a sign of their lack of interest – a major concern among delegates.

Bill Wright of the John Lewis Partnership questioned the interpretation of the IEE Wiring Regulations: "There is nothing in BS 7671 to say don't use modular wiring. Most other countries don't use armoured cables. In the USA, cable is simply fed through conduit." He used images of bundles of cables hanging in irregular patterns from installations to emphasise this point. "In France, armoured cable is not used either and conventional cable is simply clipped directly onto the ceiling," he added.

Help may be at hand in this area, reported the BRE's Liam Roche: "One of the main aims of the project is to examine the standards and regulations to see how these need to be changed and how they can be better used." Wright sees modular wiring as: "Ideal for speculative buildings. If the design is done correctly and the client doesn't change the specifications, the system will work. But the client must work very closely with the contractor.

"Only when the client, contractor and electrician begin working together will modular wiring work," he concluded.