Electrical Contracting News (ECN) October 2016 - Page 47

LIGHTING SPECIAL FEATURE

Considered collectively , these loss mechanisms can result in a decrease in efficacy of greater than 30 per cent according to the US Dept of Energy . You can ’ t do much about the driver losses but heat generation needs to be dissipated effectively as it does harm the unit – and relatively few LED luminaires are designed with adequate cooling to my mind . However , a manufacturer ’ s choice of components and the design of the luminaire for optical efficiency can all deliver improved efficiency . You could argue that the energy savings are marginal at an individual user level , but it soon adds up for a whole building or business using dozens or hundreds of lights .
Broadly speaking , if you want output similar to an old 60W incandescent , look for around 800 lumens . For the equivalent of an old 40W bulb look for 450 lumens . Do compare the output efficiency . For instance , our LED floodlights deliver over 2,000 lumens while consuming only 32W and in terms of brightness and field of illumination compete with any energy hungry halogen .
Instant LED brightness should now be a given , of course .

Quality
The biggest inefficiency of all , of course , is poor componentry or quality control so that the product needs to be scrapped or replaced . Saving a few pennies on a luminaire with a substandard driver or PIR switch , or that is liable to burn out from overheating , just does not make commercial sense . Doing a job twice is mightily expensive .
Yes , it ’ s true that LEDs generate relatively little heat – but even this is potentially a problem for enclosed LEDs , especially with outdoor lighting . Where the IP rating is high to protect the luminaire from the elements , the airflow and cooling to the luminaire can be restricted . Gradually , and eventually , the heat produced by the LEDs is going to degenerate the LEDs themselves and the electronic components surrounding . So look for proper cooling fins and pins , not just a few holes in the casing . The 30,000 + hour life expectancies we all have of LED lighting
WE NEED TO STOP BUYING LEDS ACCORDING TO THE ENERGY THEY CONSUME AND FOCUS INSTEAD ON THE LIGHT THEY GIVE OUT ( LUMENS ).
Instant LED brightness should now be a given .
these days are unlikely to be met if the circuitry is consistently overheating . So any design needs to incorporate a cooling mechanism . If the back ’ s smooth , with no cooling fins , then perhaps it ’ s a case of buyer beware !
Another consideration is the PIRs . Whether it is providing outdoor security lighting or automating internal lights and HVAC systems to conserve energy , PIR detectors are everywhere and , just when you thought these were products you could sell over the counter without too much thought , comes a warning about LED compatibility . All LED lamps and luminaires must use a type of driver or voltage reducing circuit as for AC LEDs and this driver or voltage reduction circuit can cause current spikes at switch-on
Not all LED luminaires deliver the same lumens per Watt .
Look for proper cooling fins and pins , not just a few holes in the casing .
Watts vs lumens
We need to stop buying LEDs according to the energy they consume and focus instead on the light they give out ( lumens ). Not all LED luminaires deliver the same lumens per Watt , and their efficiency is a good indication of the quality of design and construction .
While Wattage is the total power consumed by the luminaire after thermal effects , driver losses etc , lumens measure light output after optical inefficiencies , most of which are a function of the detailed design of the unit ( LED arrays , reflectors etc ).
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LIGHTING Considered collectively, these loss mechanisms can result in a decrease in efficacy of greater than 30 per cent according to the US Dept of Energy. You can’t do much about the driver losses but heat generation needs to be dissipated effectively as it does harm the unit – and relatively few LED luminaires are designed with adequate cooling to my mind. However, a manufacturer’s choice of components and the design of the luminaire for optical efficiency can all deliver improved efficiency. You could argue that the energy savings are marginal at an individual user level, but it soon adds up for a whole building or business using dozens or hundreds of lights. Broadly speaking, if you want output similar to an old 60W incandescent, look for around 800 lumens. For the equivalent of an old 40W bulb look for 450 lumens. Do compare the output efficiency. For instance, our LED floodlights deliver over 2,000 lumens while consuming only 32W and in terms of brightness and field of illumination compete with any energy hungry halogen. Instant LED brightness should now be a given, of course. “ SPECIAL FEATURE Quality The biggest inefficiency of all, of course, is poor componentry or quality control so that the product needs to be scrapped or replaced. Saving a ]œ[Y\ۈH[Z[Z\H]HX[\]\܂T] ܈]\›XXH\]Bݙ\X][\\XZH[Y\X[[K[H؈XH\›ZY[H^[]KY\]8&\YH]Q[\]H[]][B]HX]8$]][\\œ[X[HH؛[H܈[YQ\XX[H]]܈Y[˂\HHT][\YXH[Z[Z\HHH[[Y[HZ\[[B[Z[Z\H[H\XY ܘYX[K[][X[KHX]XYBHQ\[Y[\]HBQ[\[\[H[XۚX˜\ۙ[\[[ˈ܂\[[[[\H]š\[H\[ˈH \YB^X[Y\H[]HوQY[‚HQQVRSQPԑSHSTHVBӔSQHSTSPQӂHQVHUHU SQSK[[QY\[HH][\H^\\H[Z[HHY]YB\Z]H\ۜ\[Hݙ\X][ˈ˜[H\YۈYY[ܜܘ]HH[›YX[\KYHX&\[ ]˜[[[\\]8&\H\Hق^Y\]\HB[\ۜY\][ۈ\HT˂]\]\ݚY[]܈X\]BY[܈]]X][[\[Y[P\[\ۜ\H[\KT]Xܜ\H]\]\H[ \[[HY\H\HX[B[[ݙ\H[\]]›]XY Y\H\[X]Q\]X[]K[Q[\[[Z[Z\\]\\HH\Hو]\܂YHYX[\Z]\܈PQ˜[\]\܈YHYX[ۈ\Z][]\H\[Z\]] [ۂ[Q[Z[Z\\[]\H[YH[Y[\] ܈\[[[[\H]\[H\[˂][Y[•HYY^Z[QXܙ[H[\H^Hۜ[YH[\š[XYۈHY^H]H][Y[K[Q[Z[Z\\[]\H[YH[Y[\] [Z\YXY[H\H[X][ۈوB]X[]Hو\Yۈ[ۜX[ۋ[H]YH\H[\ۜ[YYHH[Z[Z\HY\\X[YX]\\][Y[YX\\BY]]Y\X[[YXY[Y\[وX\HH[[ۈوB]Z[Y\YۈوH[] Q\^\YXܜ]K ‚ MY[8$[YYX\ [ ‚LǨ M L