LED Tube Replacement

[Paul the BIG Finn]

We are being pitch a direct "LED Tube" replacement for our T8 fluorescents. You remove the old fluorescent lamp and install a "tube" of the same size which is really LED lights in a frosted tube. We have also been pitch a similar "LED Tube" that requires rewiring to bring 277V power directly through the lamp holder. They open the fixture, cut the power leads from the ballast and connect them to one of the lamp holders (the lamp holder on the other side is dead).

The "rewire" manufacturer claims the ballast will continue to burn energy, while the direct lamp replacement sales guy claims the ballast uses so little power the extra labor will never be paid for.

A couple of questions come to mind:

1. Both "tubes" put out less lumens than the fluorescent lamps they replace, but both sales guys claim all of the LED light is directed down and will deliver more light to the work plane. Is this true? Has anyone done an actual field test?

2. Both sales guys claim the LED "tubes are good for 50,000 hours and they "hardly ever burn out, just slowly emit less light. In my experience LEDs do last longer, but I have seen them just stop working. Is 50,000 hours reasonable? If it is the labor saving s will be as much as the energy savings.

3. The direct lamp replacement guy claims the lamp holder and internal wiring should be replaced if used for 277V, but the rewire guy claims replacement isn't required because the holders are "non-shuttered. Not sure why that makes a difference, but the wire inside the fixture is 18 AWG and the power wiring is 12 AWG. Shouldn't the wire to the lamp holder be 12 AWG?

4. Is it OK to abandon an unwired ballast in the light fixture or should we make them take them out?

Thanks,

 

[Dennis Alwon]

If you are getting inspected I would check out what they want. Some departments do not let you modify the fixtures without documentation.

We just did a rewire of an older home that had 40 or so fixtures in soffits. We used the 3000k 120V bulbs. We left the ballast in unconnected. I don't see a reason to remove them. Be careful if you have T* fixtures there the sockets may need to be replaced to the ones that have separate parts on the socket. Some of the T8 sockets have two wires coming out but the copper tab is continuous. You don't want to hook 277 to that====kaboom. The old T12 sockets work fine in my experience even though the tubes are T8
Now what happens if someone replaces the LED with a T8 fluorescent? Not sure but that may be a good reason to not do it.

 

[GoldDigger]

If the replacement fluorescent tube has a filament, zapp! And it definitely will not light, except briefly.

 

[Ragin Cajun]

What are they charging for those things?

RC

 

[Dennis Alwon]

What are they charging for those things?

RC

I think the 120V led bulb that replaces a 4' fluorescent - no ballast involved cost about $30 each

 

[tom baker]

Standard T-8 is very energy efficient and hard to justify an expensive change out to LED.
But there are companies that make a tray to replace guts of the luminaires. And now there are LED lamps that replace the T-8s with out removing ballast.
Ask the sales reps
Are the lamps or kit listed?
Will there be 120 volts on the tombstones?
Energy start rated?
Is it approved by the utility for a rebate?
This is our NW lighting resource https://www.lightingdesignlab.com/ they will have info on this type of retrofit.
If the lumens are less you will get complaints. Lots of complaints

 

[Dennis Alwon]

Standard T-8 is very energy efficient and hard to justify an expensive change out to LED.
But there are companies that make a tray to replace guts of the luminaires. And now there are LED lamps that replace the T-8s with out removing ballast.
Ask the sales reps
Are the lamps or kit listed?
Will there be 120 volts on the tombstones?
Energy start rated?
Is it approved by the utility for a rebate?
This is our NW lighting resource https://www.lightingdesignlab.com/ they will have info on this type of retrofit.
If the lumens are less you will get complaints. Lots of complaints

Yes there will be 120v on the tombstones and yes they make LED lamps that replace the fluorescent but the fixture must have an electronic ballast not the magnetic ones from the T12 fixtures. At least that is the case for the ones I have seen...

I have done a few types of systems and they were all listed. One I had to change the ballast and use the driver provided with the bulbs

 

[petersonra]

You can run a typical florescent tube 24/7 for about $25 per year. No amount of energy savings to replace it makes economic sense as the labor rates eat up the tiny savings.

 

[kwired]

You can run a typical florescent tube 24/7 for about $25 per year. No amount of energy savings to replace it makes economic sense as the labor rates eat up the tiny savings.

Kind of my thoughts as well - but you cant convince the department of energy or the EPA that they are not worth replacing:roll:

 

[petersonra]

Kind of my thoughts as well - but you cant convince the department of energy or the EPA that they are not worth replacing:roll:

Unless you can get someone else to foot the bill.

 

[kwired]

Unless you can get someone else to foot the bill.

Yes, if someone is offering rebates, free or reduced price on equipment, etc. you are only getting a green carbon footprint, but losing green in your wallet.

New installations are generally worth higher efficiency products being installed, but existing installs still have some value in what is there if it is working. There are times when owner also wants an updated look, and that is something that has a different value, which is not the worth the same from one person to the next.

A few years back we had rebates from POCO's around here for converting less efficient lighting to more efficient lighting. One of the primary applications encountered was T12 to T8 replacements in commercial buildings, though there were possible rebates for other items being converted. I Changed two stores from surface mounted 8 foot open strip luminaires (one of them was old luminaires installed back in 1960's) to 2x4 troffers. Owners may not even have noticed if there was any change in energy bill, but was real happy with the new look, and happy the POCO helped pay for some of it.

But I had done a study on another installation (that had decent looking luminaires and were only around 20 years old) and we just did not see energy savings payback to be enough - even with the rebates to be worth the investment of changing/converting all the luminaires. One factor was number of hours of operation a day, had this place been open/lighted more hours per day it may have helped the final results better. It was decided T12 ballasts in that installation were only going to be converted to T8 as they failed.

 

[Electric-Light]

Rule #1. Take everything LED sales people and sales oriented LED websites say with a grain of salt. The solid state fluorescent lamp generally known as LED has its place, but it's not a miracle and lumen depreciation is always more than T8 or even T12 lamps. Lumen depreciation on T8 is under 10%. LED is 30%. LEDs are tested to 6,000 hours and the time it takes to drop to 70% is predicted, not measured.

The "rewire" manufacturer claims the ballast will continue to burn energy, while the direct lamp replacement sales guy claims the ballast uses so little power the extra labor will never be paid for.

Electronic ballasts are high quality regulated power supplies. LEDs require a power supply and the quality of this power supply dictates how much flicker you will have. A very crude one like the one used in Christmas light string will flicker bad. A pin based CFL and a screw-in 120v CFL both have a ballast. It's just a matter of where. A re-wire LED lamp has a driver, which uses up some space within the tube. A drop-in uses the ballast as the driver. If you have 120-277v (not 120 only or 277 only), you should be fine. Otherwise, you should check with the lamp manufacturer.

A couple of questions come to mind:

1. Both "tubes" put out less lumens than the fluorescent lamps they replace, but both sales guys claim all of the LED light is directed down and will deliver more light to the work plane. Is this true? Has anyone done an actual field test?


Your field, my field and their field. All different. The Philips 1,600 lumen lamp claims to put out the same foot candle, but to get these values, they chose a Super Wal-Mart store with a high, dark ceiling and basic strip lights. The spilled up light is basically lost into the dark sky. It will be less successful in an indoor surface mount or a troffer.

2. Both sales guys claim the LED "tubes are good for 50,000 hours and they "hardly ever burn out, just slowly emit less light. In my experience LEDs do last longer, but I have seen them just stop working. Is 50,000 hours reasonable? If it is the labor saving s will be as much as the energy savings.

50,000 hours of predicted life is common for LEDs. In your experience, you don't know if LEDs last longer. Economically somewhat reasonable T8 LEDs probably only existed in society for about 17,520 hours T8s have been around since the 1990s and there is a lot of real life data collected including performance tests on working lamps pulled out of spent lamps. There will always be working lamps, because they can't wait until 100% of lamp fails to replace. When you stick LED lamps into a fixture, the lumen output is approximately the same as 4 foot 25W lamps. These lamps also generally last longer with a rated life of 40-70,000 hours. They start off at SYSTEM efficacy of 90-100lm/W when new or 81-90lm/W at end of life.

The best Philips LED T8 with a cutting edge CEE1 NEMA Premium T8 ballast(which I doubt your fixtures have...) gets you 110lm/W, but 77 lm/W at end of life and degradation is quicker during the first 1-2 thousand hours, then it settles down finally giving you a very close match in performance to 25W T8 48".

25W 48" T8 can't work under 60F, so the LED is a good alternative where 32W lamps give off more than enough light, but you can't use 25W lamps due to temp limitations. .


3. The direct lamp replacement guy claims the lamp holder and internal wiring should be replaced if used for 277V, but the rewire guy claims replacement isn't required because the holders are "non-shuttered. Not sure why that makes a difference, but the wire inside the fixture is 18 AWG and the power wiring is 12 AWG. Shouldn't the wire to the lamp holder be 12 AWG?

Magnetic T8 ballast or T12 ballasts should not be used with drop-in LEDs. Unless the existing ballasts are incompatible with drop-ins or they're near end of life, I'd go with drop-ins. The 2100 lumen one is about $25 a tube. Home Depot sells the 1600 lumen version for $25. Go buy a few to try out since they have a hassle free return policy.

4. Is it OK to abandon an unwired ballast in the light fixture or should we make them take them out?

Leave them in if they're not in the way. Why rack up more labor? I would still go with the drop-ins if the ballast is compatible. If you go with drop-ins, there's a chance of ballast failures and if you go with the bypass, there's a chance of built-in driver in the bulb failing. It's a wash.

Thanks,

OSRAM Sylvania drop-in

http://assets.sylvania.com/assets/Documents/LED417.ac8824e1-3f0b-4310-9fc2-34d64766e5e8.pdf

OSRAM Sylvania with proprietary dedicated driver:
http://assets.sylvania.com/assets/Documents/LED299.8e6916d5-f547-4f81-80fb-d0ee2ea66309.pdf

Philips drop-in
http://www.usa.lighting.philips.com...09BN_LED_T8_InstantFit_bulletin_10.14_Web.pdf

Philips bypass
http://www.lighting.philips.com/us_en/connect/Assets/CorePro-QIG_Mar2013_v6_web.pdf