With Part L2 and rising energy costs there has never been a greater need for building services control in mainstream commercial buildings. What is needed is a simple cost effective solution that can control lighting, heating and other services argues Colin Legg, Product Manager for Hager’s Tebis TS bus system.
We can all point to the £millions invested in major corporate headquarters and lick our lips at the prospect of the building management system to be installed. Suggest installing such a system in smaller offices, a chain of retail outlets or leisure centres however, and budgetary constraints and lack of skilled labour will soon bring you back down to earth.
Let’s face it there are only so many system integrators out there and quite rightly they charge what they are worth. Sophisticated arguments about payback in a few years through improved energy consumption only too often falls onto deaf ears – too many are still only interested in bottom line capital costs.
In fact even the most evangelist among us will realise that the trick is to introduce appropriate technology according to need. The ‘all singing, all dancing’ fully interoperable solution while an ideal is not always the best answer.
Forgive me for painting such a gloomy picture, but many of you will recognise these hard facts of life in the construction industry.
Yet there has never been a better time to argue for intelligent building services control that goes beyond the light switch or thermostat. Part L2 of the building regulations is just one reason why it should be on the agenda.
Keeping it simple
Too many manufacturers and indeed groups of manufacturers have concentrated solely on the Holy Grail for building management. Indeed arguably the Holy Grail does in fact exist, unfortunately it is often too expensive and you need trained technicians to look after it. Often the end user does not understand the functionality and any advantages are lost as a result.
For small and medium sized commercial or public sector premises such solutions are not realistic. Having said that it is possible to offer simpler scaled down versions of some systems that are flexible, future proofed and cheaper; plus they are easier to install, commission and understand than their big brothers. By keeping such systems simple more organisations are waking up to the possibility of using building services control in smaller offices, leisure centres and retail outlets as well as their corporate headquarters.
Bus systems offer just such an alternative. Let me point out that I am not referring to fully interoperable EIB or Lonworks based systems, but rather the more cost effective proprietary systems available from manufacturers, such as our own Tebis TS, which whilst utilising EIB technology has been configured as a standalone system ensuring maximum flexibility at minimum installed cost.
Broadly speaking all bus based systems work in the same way. They offer decentralised or local intelligent control. The backbone of the system is a single twisted pair cable, which acts as an information highway between the input devices and output devices. An input device might be as simple as a rocker light switch or thermostat and the output device could be a light fitting or a panel radiator.
Each device taps onto the bus cable and is assigned an address. An input device will then send instructions to certain output device’s addresses and activate them. Using bus systems simple or sophisticated multiple control scenarios are possible. Reprogramming existing devices or adding new ones is straightforward.
Installation of such systems is easy and does not involve any new skills – indeed any skilled electrician can do it. The key to broadening the appeal of bus-based technology is simplifying its commissioning and programming.
Some systems only need a half days training to understand and this is often offered free of charge to encourage product champions. This is important because suddenly such technology is in reach of a mass installer base – often the electrical contractor. Specialist programmers are not needed and those who use the building are easily instructed in how the system works and can be changed to suit their needs.
While not as extensive as a full EIB or Lonworks based system the control offered is vastly superior to a conventionally hard wired option and is appropriate for the buildings in question. After all how many Canary Wharf’s are there in the UK?
Sophisticated lighting control including scene setting, heating, motorised shutters, telephone control, intelligent power sockets, radio frequency remote switching are all achievable. Indeed by using relay devices most services such as security or smaller air conditioning units can also be added. As an illustration our own system will co-ordinate up to 128 different output and input devices, with each device typically capable of handling 4 separate inputs or outputs. Also as a Separated Extra Low Voltage (SELV) system, with the bus supply rated at 29V DC, there are many safety advantages.
Depending on the project, cost savings can also be realised at the front end when compared to conventionally wired solutions. Quite simply there is no need to supply power to input devices or switches and for several applications multiple cabling runs to a central switching point is a thing of the past. This is important because labour is often the biggest cost in an installation.
While selling in a system that offers control, future flexibility and long term savings might raise some interest, if you can keep installation costs at similar or even reduced levels you will certainly receive a positive response.
One market that has begun to use such technology is the retail industry. Staples, for example, have used our own Tebis TS to provide an energy saving solution. For the retail area a combination of a master switch and timers control the lighting. In the backroom and staff areas PIR movement detectors control lighting and heating.
At the end of the day half the lights in the public areas are turned off ten minutes after closing and the last person leaving the building turns all the lighting off using the master key switch.
The bus system offered simple installation and commissioning; typically each store took just two days to refurbish and there was minimal disruption to the public and staff.
Often bus lines are installed to provide basic control initially but then more is added at a later date with minimal disruption. Labour savings generally offset the extra cost of installing such a system.
For organisations with multiple sites, bus systems are offering real benefits.
In our experience building services managers or consultants specify such systems and what they control and then let installers get on with putting the system in and the basic commissioning. In this way it is possible to configure control for smaller multiple sites in a cost-effective way.
Such systems also introduce technology to more people and begin to erode misconceptions and fear. It is certainly worth exploring what proprietary systems are available and what they can achieve.