Sparks Electrical News March 2019

LIGHTING

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CAN YOU DIM 100X 5 W LEDS WITH A 500 W DIMMER?

A lthough LED lighting technology provides numerous advantages for the end user, for the installer or specifier, this new technology often creates headaches when it comes to practical implementation. One of the problems frequently encountered is the question of howmany LEDs can be dimmed with one dimmer. Surely a 100 W dimmer for example, should be able to dim 10 x 10 W LEDs, since it is able to dim 2 x 50 W halogen lamps? Unfortunately, LED loading cannot be calculated the same way as a traditional incandescent or a mains halogen light bulb. It is the exception rather than the rule that a dimmer can dim up to its full wattage rating of LED load. While the LED lamp may

In the absence of knowing the Halogen or GLS rating, the only way to know for sure what the maxi- mum load will be for a particular LED lamp or fixture and dimmer is to test. Shuttle Lighting has tested hundreds of different LEDs and posts the results online, http://shuttlelight- ing.com/lamps-and-dimmers-that-work-together/ – an excellent resource in determining load and compatibility. However, remember that a key factor in the world of LED lighting is the rate of change. LED modules are being updated continuously, so Shuttle conducts new tests for dimmer maximum loads and compatibility.

ing of the dimmer and divide it by the equivalent or replacement GLS or Halogen rating of the LED. The maximum load of the dimmer divided by the equiva- lent wattage (HAL/GLS) = the maximum number of lamps.

only draw 10 W continuously, it may have a start-up inrush current or repetitive peak current during every half-cycle that makes it appear much worse, i.e. be- haves like a higher wattage load. For example, when using an LED load, a 500 W incandescent dimmer with a 5 W LED lamp does not necessarily imply that 100 lamps (500 divided by 5) can be used on the dimmer. While the LED lamp may only draw 5 W continuously, it may have a start- up inrush current or repetitive peak current during every half-cycle that makes it appear much worse. The 5 W LED lamp can cause the same stresses on the dimmer as a 70 W incandescent load, depending on its inrush and peak current. A good rule of thumb is to take the maximum rat-

Enquiries: www.shuttlelighting.com

MOTION ACTIVATED CEILING TRI-LIGHT

C onsumers can arrive home to a fully lit ga- rage, home or entrance area with this new motion activated ceiling tri-light. The prod- uct is a simple fit as it screws in just like a light bulb. Nothing has been overlooked in the design as the unit has three retro cast aluminium heatsink faces which are adjustable, and each of the three faces incorporates an ultra-bright daylight white LED en- ergy saving light panel all linked, with stainless steel braided cables. The unit is guaranteed for 50 000 hours of light and offers 3000 lumens. It comes equipped with an on/off switch for the motion sensor on the light, which detects movement of people and cars. The fitting incorporates a 60 second timer which shuts off automatically. “This new unit is something that most customers will want and will use as it is very convenient and improves safety and security,” says Dale Engelbre- cht, Commercial Director at Vermont Sales. “Plus, anyone can fit this unit as it simply screws in like an ordinary light bulb. Every garage should have one, but it can be fitted to any room or area where you want automatic, instant light.”

Enquiries: +27 (0)11 314 7711

SPARKS ELECTRICAL NEWS

MARCH 2019