Simon Perrott Agencies offers a lighting design service to M&E Consultants, Architects and specifiers.  This service is also available through electrical wholesalers that stock and distribute commercial fluorescent lighting made by Cryselco Lighting Ltd., one of the companies represented by Simon Perrott Agencies.

To find out more about Crysleco Lighting go to: www.cryselco.co.uk

LG7

LG7 is Lighting Guide 7 issued by the Chartered Institution of Building Services Engineers.

This document covers a broad spectrum of issues concerned with lighting in offices including daylight, glare, colours, contrasts, reflection and lighting design processes.  The part that most people focus upon is the section concerning illumination values for walls and ceilings.  These were introduced to counteract the ‘tunnel’ effect created by the use of Category 2 louvres in modular fluorescent lighting.

LG7 applies to the lighting design and not to how a luminaire is constructed.  LG7’s technical requirements can be met in many ways using a very wide range of luminaire types.  Some luminaires have characteristics to assist with easier compliance with LG7 but, fundamentally, it is the overall design that has to comply.

Broadly speaking the requirement for offices with a ceiling height greater than 2.4 metres is 50% of the working plane lux level is to fall upon the walls with 30% of the level falling upon the ceiling surface.  LG7 allows the designer some flexibility to take account of physical limitations, design aspirations and economic viability with the presumption that the designer is sufficiently competent to make these decisions.

For more information about LG7 go to:         www.lg7.info/index.html

To buy a copy of LG7 visit the Bookshop at: www.cibse.org/

Look Out For Computer Designs

There are now several excellent lighting design software packages available and, as a tool for the trained and experienced designer, they offer real benefits.

In reality, some of these packages have been made freely available to contractors and wholesalers and, no matter how good these design packages are, they do not train the user or teach the user how to interpret results.

Two problems seem to occur regularly due to lack of user competence:

a) The person doing the calculation bangs in the room sizes, clicks on a fitting, sees how many lights it takes to reach a certain lux level and then has no idea how to interpret the other information or how to check that this is the most efficient solution.

b) The end-customer sees a computer print-out and, because it’s from a computer, makes the presumption that this is the best possible result.

One way that this can be seen is by the proliferation of twin 55w PLL direct/indirect fittings being put into all types of offices.  There’s nothing wrong with this lamp package, it’s just that it’s not suitable everywhere!

We have been able to re-design several proposed lighting schemes of this type, reducing lamp wattages and changing types to provide the end-user with better uniformity and comfort and energy savings of up to 25%!

The moral of this story is that if you’re being offered a lighting design service by a lighting sales rep or wholesaler, check that the person offering it has had proper training and is experienced enough to meet yours or your client’s expectations.  If not, you may be paying for his or her shortcomings on every electricity bill for the lifetime of the installation.

Simon Perrott Agencies has over 25 years of lighting industry experience behind it.  This experience includes managing quality systems within fluorescent manufacturing, carrying out thermal and safety testing, overseeing approval processes, sitting on technical industry committees, luminaire design, lighting system design and technical involvement with many hundreds, if not thousands, of successful lighting installations throughout the UK.

Building Regulations – Documents 2A and 2B

These documents are titled “Conservation of fuel and power in new buildings other than dwellings”.

In providing legal parameters for acceptable energy efficiency these documents place an onus on designers and installers to provide proof of the energy efficiency performance for the lighting installation.

Contractors are going to struggle to obtain sufficiently accurate technical specifications from the cheap product sector of the market.  This leaves two options:

1) Contractors will prefer to use quality manufacturers who can provide technical support for their products, or

2) Contractors will use a cheap alternative and use the figures provided by another manufacturer.

If you or your contractor follows the second option bear in mind that sooner or later figures are going to start being checked thoroughly and cheap fittings with cheap ballasts will nearly always be less efficient.  If it gets picked up it’s a very expensive problem to fix!

Cryselco Lighting, which we represent, provides full, accurate photometric data for virtually every luminaire it supplies.  They also produce a useful L2 Specification Document to help with L2 calculations which shows Light Output Ratios (LORs), circuit watts and lumens per watt figures for all of its product range.

If you are the installer, when making your lighting energy efficiency performance statements for L2, you are signing a legally binding declaration. 

For information on Cryselco’s Photometric Data go to:

www.cryselco.co.uk/photomet.html

HF - You Get What You Pay For

Lighting costs money.  Good lighting costs good money. 

There are now numerous companies supplying high frequency control gear from overseas.  Some of these are supplied as a product for use by a lighting manufacturer or are supplied already fitted within a complete product.

Some of the problems we have seen with the ‘cheap’ high frequency ballasts have been that they were unable to strike Triphosphor lamps.  We think this was due to triphospor lamps not being available in the market where the gear was manufactured and the ballasts were unable to recognise the lamp so shut down.

Cheap HF ballasts may also be less energy efficient, not enhance lamp life to an optimum level and may be manufactured by a company without the specialist lamp knowledge necessary to produce the best quality of product.

Cryselco Lighting only uses ‘branded’ control gear from leading control gear manufacturers.  These included, but are not limited to, Vossloh, Helvar, Tridonic Atco, Osram, etc.

Having chosen your light fitting it is equally important to choose a good quality lamp.  Good quality lamps will have longer lamp lives and may save you money.