With key lighting season upon us there are many questions and challenges that installers will face. Here, we put those commonly asked contractor queries to a selection of the industry’s top brands.
Q. HOW CAN I DIM A COMMERCIAL LIGHT FITTING? NVC Lighting UK
With residential light fittings, the dimmer is usually on the wall, separate from the light fitting. Provided the fitting, or the LED lamp, is described as dimmable, and the dimmer used is described as being suitable for LEDs, you should be OK. With commercial fittings such as battens, panels, downlights or bulkheads, it’s a different story for two reasons.
Firstly, the dimming is done by the driver, not by a dimmer on the wall, so you have to specify the right driver when ordering the light fittings and your wholesaler will usually need to order them in.
Secondly, you need to decide how the end user is going to tell the drivers to make the fittings get brighter or dimmer. There are three methods, and once you have chosen one you’re ready to tell the wholesaler what to order.
They are:
DALI
Usually, a DALI signal will be generated by a sensor or a control system. Manually operated rotary knobs that generate a DALI signal are available, but if pure manual control is required we would recommend switch dim as the simpler solution.
Switch Dim
Switch dim is a means of controlling a luminaire via a retractive switch. It is a low-cost, intuitive and easy-to-install approach to providing manual dimming control. All you need is one, or several, retractive “push-to-make” switches to place on the walls and a driver in each light fitting that will respond to a momentary mains input. Driver manufacturers use different terms, but switch-dim, push dimming and press-dim all mean the same.
Corridor Function (CF)
Corridor function can be operated by an occupancy sensor, time switch or manual switch. When the switch contact is made, the light output will be 100%. When the contact is broken the light output will be 10%, or whatever value that is programmed in the driver or control gear. As its name suggests, corridor function is designed for use in stairways and corridors.
Q. WHAT PRODUCTS ARE NEEDED TO MAKE MY INSTALLATION UGR COMPLIANT? Red Arrow Electrical Distribution
While it is possible to buy ‘UGR<19 luminaires’, there’s no guarantee that solely using these products will make your installation UGR compliant. In fact, you can create a UGR-compliant installation without using any UGR<19 products at all.
Unified Glare Rating (UGR) is a measure of glare in any given environment – not a measure of glare from a single luminaire. That means that a UGR value for an area isn’t dependant on a specific fixture, but rather the room it is located in; its shape, size, the surface reflections of walls, ceilings, floors and so on.
As such, creating a UGR-compliant installation requires more than just UGR ‘compliant’ products; the lighting design for the space needs to consider how much glare will be produced, based on the aforementioned factors.
Different UGR ratings are required depending on the space and the type of activities it’s used for. The standard BS EN 12464-1 (Lighting for Indoor Workplaces) provides a list of the maximum recommended UGR values per type of room and type of activity, across more than 280 different applications.
Office lighting, for example, has a recommended UGR of 16-19, while an industrial environment with heavy machinery in operation can have a UGR of 22 to 25. A UGR rating above 28 is deemed unsuitable for work lighting.
Q. HOW EASY IS IT TO CHANGE THE BEAM ANGLE AND COLOUR TEMPERATURE POST-FITTING? Megaman UK
Everyone has their own personal preference when it comes to lighting colour temperature and beam angle. However needing to amend the colour temperature or beam angle of a fitting mid-job can sometimes be more trouble than it’s worth.
Many a contractor will have reached the end of an install and then been asked by a customer to switch a full set of downlights from cool to warm white or vice versa, having already ‘made good’ the surrounding wall.
Alternatively, you may have reached the end of a job and realised that one lamp is operating on a different colour temperature to all the others. This can result in having to pull down barely dry plaster to remove the fitting and start from scratch, often causing damage to the underlying plaster board in the process.
Thankfully this no longer needs to be the case. As fixtures develop and become more adaptable, it is now possible to source innovative downlights, such as Megaman’s TEGO 2, which provide a variety of beam angle, colour temperature and bezel styles, all easily changeable in-situ, without having to remove the fixture from the ceiling.
With these products, the colour temperature can be altered by twisting the lamp lens itself, while the beam angle can be changed by pressing the lens into the fixture. As a result, should a customer approach you wanting to make changes, these are all possible without undoing or damaging your previous work or having to worry about ‘making good’ all over again.
You can even demonstrate to the customer how flexible the fixtures are so that they can make amendments themselves should they wish to change the lighting again in the future.
Q. WHAT ARE THE KEY CONSIDERATIONS WHEN INSTALLING FLOODLIGHTS? Anthony Parkinson, Technical Manager, Ansell Lighting
Floodlights are a great solution for almost all external domestic and commercial applications to illuminate a larger open space or provide security to homes, but there are a number of considerations to take into account – including type of product, optimum height, sensing distances and output.
Symmetric floodlighting – which produces a beam angle of approx. 120 x 120° – is ideal for homes and gardens, while Asymmetric floodlighting, with a narrower beam angle of approx. 120 x 60°, is best utilised where light pollution may be a consideration.
Then it’s all about the installation location – considering the environment and any external factors that could impact the intended illumination or spill light onto surrounding properties.
If using a PIR, you should avoid positioning close to trees or shrubs which can cause false triggering during windy weather and heat sources such as flues, which can also trigger the light. Also avoid positioning too close to bright lights as this can affect the functioning of the PIR when the Lux level is set to dark.
A key component of the installation, specifically when utilising a PIR, is the mounting height. Issues with the sensing distance not being achieved are common and are usually due to it being mounted either too high or, in some cases, too low.
The manufacturer’s instructions and guide will give safety related information and installation instructions, but as a guide the beam range of an LED floodlight is approximately three times the installation height, so if you install a light at 3m height the beam will reach about 10m – enough for a small garden. The tilt of the floodlight is also important to illuminate the space intended – if the tilt is too high or too low it will limit the sensing distance.
And in turn the level of illumination is key. An 8W LED will deliver the same output as a 100W halogen bulb, which should be plenty for most domestic installations, while a 15W LED (equivalent to a 200W halogen) is ideal for installation heights up to 12m so suitable for larger domestic or commercial buildings.
Q. HOW CAN I SAVE TIME WHEN INSTALLING CEILING DOWNLIGHTS? Hylec
Modern new builds and re-wires/refurbs of existing domestic properties often mean contractors having to install as many as 16 or 20 ceiling downlights in a large kitchen/breakfast room, plus probably another six or eight each in a couple of bathrooms. That’s a lot of time up and down a ladder with all the components!
Hylec invented the Debox junction box to save time, effort and money on this type of job. First launched in 2015, this design has now expanded into a popular series of time-saving junction boxes.
The latest addition to the range is the new Debox SM40, which is specifically designed to fit inside the 40mm ceiling apertures of today’s ceiling downlights.
The smallest in-line junction box in the range, it’s supplied complete with all components, including a 4-pole terminal block suitable for round cables, maximum 24A, and can be wired in seconds.
Using Debox SM40 simply requires the installer to insert the cables into the 4-pole terminal block and tighten the terminal screws, lower the tool-less cable clamps and secure the lid with the supplied locking clip. The locking clip can only be opened with a tool, which complies with current regulations.
Debox SM40 is supplied with a spare locking clip, so that should it need to be re-opened subsequent to initial fitting, it can be re-secured with the second locking clip. There are multiple fix-to-surface options, including using the detachable external fixing lugs found on either side of the Debox.
Q. WHAT HAPPENS IF I FIT AN LED FLOODLIGHT AND MY CUSTOMER’S REQUIREMENTS CHANGE? Andy Douglas, MD, Timeguard
You know the scenario all too well, where you’ve just completed fitting an LED floodlight, or are in the middle of it, and the customer changes their mind.
This normally means a trip back to the wholesaler as the chances of you having a suitable alternative LED with PIR to the floodlight you’ve installed in the back of the van are unlikely and, even worse, if you’ve already installed the fitting a week, a month, or even a year ago, and they change their mind, then what you take out is basically scrap. So what’s the solution? Is there even one?
On the back of customer feedback, Timeguard introduced the LEDPRO modular floodlight system range in 2016, a unique collection that offers high quality LED floodlights from 10W through to 100W.
Each stand-alone LED floodlight can be further enhanced by adding your choice of a PIR, Photocell, RF remote controlled PIR and now, a new Wi-Fi camera module, all by simply replacing the back wiring cover and plugging-in the new PIR etc. Furthermore, there’s no extra wiring involved!
On top of this, we even went one step further, adding an extra slave terminal to each floodlight to allow the same control to other luminaires.
So, the next time your customer changes their mind, you’ll already have your answers and fittings ready.
