LED Lights Power Draw Measured

[Greg R Bradley]

People just seem to lose their brains when thinking about converting to LED. It's almost like a religion or something where they "just have faith" that they are brighter and last longer even when faced with the reality.

I've regularly looked at converting 996 T-8 bulbs in one business every 5 years when they are due for replacement with 24x7x365 use. That is 43,600 hours but we have had some failures when we tried to push them to the 52,500 hours when replacing them at 6 years. The failure rate with LED is too high, the light drop off too fast, and minimal cost/energy savings. All the cheap LEDs fail way too fast and since the phosphors are similar to florescent that give them a pleasing CRI, they get ugly with time. Anyone thinking of using LED as a way to stop replacing bulbs is using the wrong florescents or just hasn't seen the effect of their misjudgement yet.

I am saddened just about every time I go to Costco and see some fool loading up a cart with a bunch of $20 LEDs. Those units make a lot of sense when you buy one or two for task lighting and temp use but when you buy 30 and start using them for shop lights, you are a fool. I stuck 4 in an area for temp use until we could have lighting added in that area. In 2 years, the lighting fall off is noticeable. They will clearly hit the garbage before making it 4 years.

I changed over 6 offices, each with four 2 lamp florescents. I used a different brand of LED conversion of each. After 3 years, every office has at least one dead bulb and several have partly dead lamps also. Maybe worth doing the conversion as they were T-12 originally, the conversion would have been a horrible failure if they had been T-8 fixtures. Not to mention every office lost some light and most required careful rotation of the LED bulbs to give acceptable lighting. T-12 and T8 have even light, not the overly directional crap of LEDs.

Here is what gains you light: CLEAN Fixtures & covers and any NEW light fixtures. Also critically important is GOOD florescent bulbs, not the crap at the BORG.

LEDs are working out pretty well in less used areas with motion sensors. LED have some real advantages in lights that go on/off many times a day.

[Ben Rivel]

I pretty much never have tubes fail, so I guess I'm stuck with them forever. Maybe it's weather? My shop lights tend to be on for several hours about four days a week. I can't find any justification to change existing ones for LED, but the last time I added lighting it was all LED strips.

Me neither.

[Carlos Alvarez]

The only thing sadder than treating LEDs like a religion is the anti-LED people who treat that as a religion.

LEDs are getting better and cheaper every day. I've finally converted the entire house except for the shop, and wouldn't go back. It's no longer even relevant if we leave lights on all the time. I wanted an outside motion light, then realized that with a 7w LED, there's not even a reason to spend the money for the motion fixture at all. Just leave it on.

[Chris M Pyle]

Which Costco LEDs did everyone purchase?

[Jim Becker]

Which Costco LEDs did everyone purchase?

Feit Electric...whatever was the deal du jour at the time. The specific model has changed. In my shop, I have two different versions of the fixture plus a bunch of the retrofit LED "tubes" in T12 fixtures.

[Mike Heidrick]

In 12+ years I have had 8 for my 24 T12 bulbs burn out in my old shop. I do plan to replace those with costco LEDs fixtures. New shed has 18 6-bulb T5 High output lights. A $20 Costco LED fixture at 16' is not going to give me what I want. Dont much care what it costs. I spray foamed the ceiling - that crap will NEVER pay back money wise but the comfort and the material properties for the env in there are amazing.

[Bob Bouis]

I put T5HOs in my shop about five years ago. It proved to be a mistake -- I didn't have any bulb failures, but all the bulbs came unglued, for want of a better word, as the caps are loose and are only attached by wiring or whatever it is that connects them to the inside of the tube. Out of six four-lamp fixtures, one became inexplicably dim and one had two of the lamps quit.

They also make a *lot* of heat and aren't terribly efficient in terms of light output per watt.

[Curt Harms]

There isn't much of a gain when going from T8 to LED.

At work I look at the cost reduction every year and we're not there yet.

At home I have T8 lighting, it would never pay for me to convert to LED unless they drop to about twice the cost of T8 lamps......Regards, Rod.

For me it was about more than cost. I expect the LEDs to be more durable when being power cycled several times per day and as stated above the LEDs sure seem brighter no matter what the labels state.

[Jack Frederick]

When I built my shop, 30x34, three yrs ago I installed 16 4'x2 bulb LED's from Costco ($35@). Set them up in quadrants with motion sensing for auto off (required by code here). nice lighting and they come up right away rather than having to wait for fluorescents to warm to the task.

[Dan Schrecongost]

Interesting that in your case and ours, actual wattage is less than the sum of the fluorescent bulbs stated wattage.

This is usually the case with electronic ballasts, which can be designed to drive standard T-8 lamps to produce normal light levels, high or reduced light levels. Usually a pair of "32 watt" T-8 lamps and a normal light output electronic ballast will draw 59-60 watts.

Older fixtures with magnetic ballasts usually draw 7% to 10% more than the nominal wattage of the lamps (tubes). Magnetic ballasts don't perform well when it is cold. When viewed through a digital camera, you will usually see yellow-ish bars of discoloration in the viewfinder; electronic ballasts operate at much higher frequencies and these bars do not appear.

There is a wide range in LED replacement lamps in terms of watts drawn and light output (measured in lumens). Overall, LEDs produce more light per watt, but your energy savings and relative change in light level depends on the specific product you select. Do pay attention to the color, which is rated in degrees Kelvin. Higher numbers indicate a more blue color of light that dampens your perception of colors, especially reds.

[Jerome Stanek]

When I changed mine out I only ordered enough for half the fixtures as I was only going to change out the half of my shop that I use and not the storage half. I ended up only needing every other fixture and it was still brighter then the T8 I had so I used the other half in the storage part also. I did change out the bulbs in the CNC room also and that to was way brighter.

[Dan Rude]

You might check out IBuild it on You-tube he even made his own fixtures for them. They come on right away and no Ballast to go bad. I have replaced all my lights with LED. Savings can be small, but they come on right away. I started years ago when, they were more expensive than now. Overall, my failures happen in the warranty period. I also replaced to get away from the Hazards Material in the florescent bulbs. I always dreaded clean up if they broke. Dan

[Bill Dufour]

Be aware you need to spend a lot of money to get a true RMS meter that accurately measures AC power. measuring ac amps with a medium price meter is not accurate. But comparing relative amps with the same meter at the same voltage is probably good enough.
Bill D.

[Jim Andrew]

Bought 4 sylvania 4100k led bulbs to replace the bulbs in a T12 troffer fixture. Cost 7$ each bulb, supposed to do away with ballast, but my problem is finding a wiring diagram for re-wiring the tombstones without ballasts?

[Ole Anderson]

Bought 4 sylvania 4100k led bulbs to replace the bulbs in a T12 troffer fixture. Cost 7$ each bulb, supposed to do away with ballast, but my problem is finding a wiring diagram for re-wiring the tombstones without ballasts?

(from my 9-22-17 thread): My 4' troffers had a metal cover down the middle, accessible from the bottom, you just squeeze and pop off to expose the ballasts. Make sure you don't have shunted tombstone caps (I think only are used with instant start, not rapid start ballasts). If so, they need to be replaced. Cut the wires to the end caps fairly short on the end opposite where the 120v wires come in. Those go to the dead end of the new tubes. Leave the wires longer on the other end. Pop off the end caps to see which wire is the common, on mine, I think they were yellow. Common goes to the white (neutral) 120v incoming. Strip and twist the other three wires together (black, blue, red) then wire nut those to the incoming 120 v hot black wire. Toss the ballasts and replace the cover, install the tubes and you are done. After the first one they go easy. I think I spend 15-20 minutes per 4 tube troffer working on a Baker scaffold.