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PRODUCTS & BUSINESS SOLUTIONS
LIGHTING SEASON:
QUESTION TIME 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 manufacturers.
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.
Q
HOW Can I DIM A COMMERCIAL LIGHT FITTING? NVC Lighting UK
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.
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