How TLED retrofits can alter systems. Going beyond FC and lumens in specifications

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Electric-Light

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T8 TLEDs have different pattern than T8 lamps. The difference may ruin a system, have minimal impact or can you believe this? possibly enhance it under the right circumstances.

I will break down how energy service sales companies faithfully pitch foot candle incorrectly.
Lumen can be compared to weight while FC compares to pressure. "one foot candle" means one lumen per square foot.

12 x 16 garage is 192 square foot.
Your van weighs 4,500 lbs.
Average lbs/sf is calculated by dividing the weight by area.
The floor load is 23.43 lbs per square foot.

If you setup barriers along the edges and fill it up with 4,500 lbs of cement, it's also
23.43 lbs per square foot.

Visual representation changes everything.
23.43 lbs per square foot with no visual is often meaningless.

A visual representation shows you that you're at about 4,500 lbs/sq.ft
under the tires assuming all four tires share the weight equally.

A visual representation gives semi-objective view of light pattern. Specification qualifiers allows you to express them in words and numbers so you can communicate instead begrudgingly compromise for an LED proposal that do not meet reasonable (over used word...) expectations, because you're not able to communicate what you want in words.

A 0-60mph seconds in a car commercial gives you some indication of acceleration performance.
A car that does particularly well "in class" in passing may provide a separate 45-60mph time too.
But... what if it shifts so harsh that you feel like someone rear ended you every time the gears change? If there was a "filter" statement that limits the amount of "jerk" it takes away the short cuts that can be used to get the sales specs they want.

Here's an example of visual representation. You have an idea of how much, where, how smoothly the gradient is with a quick view.
jPPHAoT.png


Left: before. right: after
When you just rely on energy sales vendor to retrofit an existing system, they can make your system look like this. The average FC would be the shade of grey if you were to blend the entire area. The sales performance evaluation may just take the FC at the bright zone so he can say he saved you energy and increasing FC at the same time leaving you full of sudden transitions, uneven lighting, visible lines in shadows, etc.

zIvwDrdl.png


A common symptom of retrofits that give up diffuser to squeeze every bit of lumen to make their numbers look good. Increased shadows. Shadow casting lights are used for exhibits and retail display, but is this a desirable quality for the area you're getting a retrofit?

You're not in control if you're letting energy sales retrofit company churn out the numbers they want. They need to put a light sensor on top of a toy truck and drive all around. Before and after and map out the uniformity.

TxYyryN.jpg


Columns show different types of fluorescent fixtures. They're not the same. Far left column is the pattern of bare lamps.

Rows show how TLEDs influence the pattern which may ruin the system.
3rd and 5th columns show examples of fluorescent fixtures with excellent uniformity in lighting.

LED bloats the 3rd fixture and weighed light distribution becomes like that of overinflated tires.
The 5th becomes flat and weight shifts to the sides.

Parabolic + mid angle range and "high performance" + narrow appear to produce the most noticeable unsightly grooves and poor uniformity.

If the lighting system is properly designed for the current use, the retrofits ruin the lighting system. It only improves it when the LED drop-ins induce a distortion that is favorable for the long term application of the illuminated space. Some fixtures gained in delivered lumens per watt with bottom emitting LEDs at the compromise of ruining the beam pattern.
Volumetric fixtures were essentially unaffected other than diminished output due to substantially lower total lumens of TLEDs.

KtZUZdX.png


  • Wide: 160 degree beam. DIFFUSED 1,973 lumen Miracle LED 48" 19.6W 6000K 160*
  • Mid: 133 degree beam. DIFFUSED 1,844 lm 22.5W 4100K 133* InnoGreen IG-220DT8120-20-NW
  • Narrow: 105 degree beam. CLEAR 1607 lm 18.3W Toggled MK2M-T8-48-UN19ND-4080D2-A1
 
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