Thoughts on replacing 175w MH lamps with line volt 50w LED 'bulbs'?

[milemaker13]

The atrium in our building has a 21' ceiling height. There are 16 recessed fixtures up there, several of which cannot be reached with ladders or the tiny lift that only goes straight up. Standard doors and ceramic tile floor prevent a boom lift. I am going to have to rent scaffolding to get to these fixtures.

The fixtures run 175w MH bulbs with external ballasts. We have replaced a dozen or so bulbs and half as many ballasts in the 5 years we've been here. The glass lense prevents successful bulb replacement with the "long stick".

I recently had a good experiance with LED while illuminating our flag pole and had the idea that maybe I could do something similar with the atrium lights, if only to allow more time between re-lamping.

I found bulbs made by Light Effecient Design, model LED8045M42. They are 50w, 277 volt 'bulbs'. They actually look like an oversized LED flashlight with a mogul base.

The current MH bulbs put out 14,400 initial lumens (9300 mean) vs. the LED at 4446 lumens. Both have a color temp of 4200k.

Has anyone had luck with this kind of retro fit? I've read a lot online and they seem to all agree these are suitable replacements. I'm worried that the folks in the front offices won't "like" the new light. My worst fear is after installing them, they will complain and want them changed back.

It is a pricy investment, around $3600 plus my time to swap all 16. I've done a little homework and discovered an $11k savings over the stated 50k hour life.

What do you all think here? Again, even if the actuall savings are less but the re-lamp time frame is 5x greater that is still a victory in my opinion.

There is another benifit that I can see.. Future bulb changes can be done with the "long stick" because I will be removing the glass lense from the fixtures. Hoping to never again have to climb a 20' scaffold in the fron t lobby. :thumbsup:

 

[Npstewart]

You are essentially going to be removing half of the lighting in that area if you are going from 9300 lumens to 4446.

The proper way to do it would be to buy a foot candle meter for $100 bucks and measure the current light level about 2.5 feet above the floor and then have photometrics done with the new LED fixtures getting as close as possible to the original unless you think that area is over-lit with the existing metal halide fixtures. Most manufacturers will do photometrics for free. There are also some free photometric calculators online.

Whenever I do a cross over, I always do a 1:1 lumen change out.

Also, your new LED fixtures are around 89 lumens / watt which isnt bad but there are better ones out there to give you more light per watt. Obviously the price goes up with it.

 

[mjf]

Change 1 of them that is easy (easier) to access and see if the front office likes it.

 

[milemaker13]

Most articles I read online suggest that the reason the lumens can be less is because they shine down only, not omni directional like the traditional MH bulbs. They say that basically those extra lumens are being wasted. It kinda makes sense when you think about it like that.

The light meter is a good idea, but almost half these bulbs are out now so that won't give me an accurate reading.

I'm not going to change fixtures at all. I would simply bypass the ballast to apply line voltage to the socket. Then these LED bulbs screw into the existing socket.

All 16 fixtures are in one area, the front atrium (foyer, entryway, ect), as opposed to say a hall way. So while it would be nice to see what one would look like first, i'm not sure it will show us what these would look like.

I wrote an email to the company asking some of these questions. I've done my homework, but want to hear what the sales company says about them. Anyway, still debating and waiting for input from above.

Can you suggest a better LED source? One big concern is the quality of these products.

Thanks guys.

 

[Npstewart]

After thinking about it, 88 lumens per watt is actually as good as your going to get. The higher the power input, the less efficient the LED downlights are ive noticed. All the manufactuers I use max out at 3,000 lumens so if you found a 4,700 lumen downlight and you are still getting 88 lumens / watt, thats pretty good. I would still do photometrics either way on this assuming your manufacturer has a .ies file for those lights. A 21' ceiling height is challenging with an LED downlight if you dont have the option of adding any additional lights. I agree with your point that the LEDs will provide a more direct light source on the ground but cutting it down to 1/3rd seems extreme.

 

[milemaker13]

Unfortunatly for me, I don't disagree. Cutting the lumens that much concerns me. I really don't want to end up with all this in my lap:weeping:

I am still researching:thumbsup:

Its looking more and more like I will just have to suck it up and relamp with MH. Probably throw a new ballast in the hardest to reach fixtures just for good measure.

 

[Electric-Light]

Unfortunatly for me, I don't disagree. Cutting the lumens that much concerns me. I really don't want to end up with all this in my lap:weeping:

I am still researching:thumbsup:

Its looking more and more like I will just have to suck it up and relamp with MH. Probably throw a new ballast in the hardest to reach fixtures just for good measure.

There are a few true drop in replacement with improved color rendition along with better efficiency.
Sylvania MetalArc Powerball or Philips AllStart drop-in 145W
CRI is 80-90. R9 of 40+ which is above most light emittus decos
http://www.usa.lighting.philips.com/pwc_li/us_en/connect/tools_literature/downloads/411074.pdf

 

[milemaker13]

My boss is leaning towards the change over. :thumbsup: She wants a couple more days to think it over.
This is the salesman's reply to the question of lumens vs lumens:

The LED lumens listed are delivered lumens and the MH lumens listed are total lumens. Of the total lumens only about 1/3 reach the ground (delivered lumens). That is why the LEDs are so energy efficient, because they do not waste light where it is not needed. Also we recommend using 5700K daylight color which will appear much brighter than the 4200K of the existing MH.

 

[George Stolz]

My boss is leaning towards the change over. :thumbsup: She wants a couple more days to think it over.
This is the salesman's reply to the question of lumens vs lumens:

The LED lumens listed are delivered lumens and the MH lumens listed are total lumens. Of the total lumens only about 1/3 reach the ground (delivered lumens). That is why the LEDs are so energy efficient, because they do not waste light where it is not needed. Also we recommend using 5700K daylight color which will appear much brighter than the 4200K of the existing MH.

I think it's clear that you are not being whimsical in your approach to this, and if it doesn't work out as hoped I would not lose sleep over it. You didn't build the lamp, your buddy didn't build the lamp, your motive is obviously to benefit the company.

Good job, and I think the boss will sign off on it.

 

[Ragin Cajun]

My boss is leaning towards the change over. :thumbsup: She wants a couple more days to think it over.
This is the salesman's reply to the question of lumens vs lumens:

The LED lumens listed are delivered lumens and the MH lumens listed are total lumens. Of the total lumens only about 1/3 reach the ground (delivered lumens). That is why the LEDs are so energy efficient, because they do not waste light where it is not needed. Also we recommend using 5700K daylight color which will appear much brighter than the 4200K of the existing MH.

ENOUGH, I can't keep quiet!!

MH fixtures are 60 - 80% eff, NOT 33% as claimed by the led shill.

One for one will not give much light.

RC

 

[milemaker13]

No need to keep quiet... I mean, thats why we're all here isn't it? I welcome your input.

Can you please elaborate? One for one meaning lumens? Watts? Bulbs?

I do more machinery installs,troubleshooting and repairs. Lighting has always been the thorn in my side. So many options....

While I understand MH to be very effecent per watt, I think the point being focused on in this case is the effecency of an omni-directional bulb is a recessed can light application (down lighting). I'm led to beleive this is why an LED could work well in this case.

This is a nerve racking experiance for me as I am proposing an expensive change over and have flip flopped in my own mind several times. So by all means, please, explain your feelings on the subject.

Thanks Cajun

 

[Ragin Cajun]

I do a fair amount of lighting design..

Give me a day or so to think about your situation.

I remember at a Hubbell seminar at their headquarters here regarding a replacement for HID. HOWEVER, to get the true light equivalent the fixture was quite large.

RC

 

[Ragin Cajun]

milemaker13,

What brand and cat # fixture are you looking at?

 

[Electric-Light]

High kelvin isn't desirable in many places.
Fluorescent lamps are available in 3000 to 6500K.

Most preferred types for commercial lighting are 3,500 and 4,100 and they're the highest volume lamps. Not 5,000 or 6,500. Those higher CCT lamps are used at very low illumination level to create perception of more bright. In other words, LE Decorations need the compensated power to create the sense they feel "just as bright" in lacking lumen output.

 

[milemaker13]

I couldn't tell you that. I am using the fixtures already in place. They are pretty basic recessed can lights. The LED lamp I am looking at is by Light Effecent Design. Model #LED8045M42, although that # is the 4200k lamp. It is being suggested to use the 5700k lamps. I suspect that part # will end in M57.

I am looking to buy from synergy lighting out of Florida. I can get them a couple bucks cheaper elsewhere online, but these guys have been pretty good in helping me out. In fact, they have offered to send one bulb to test out and if we don't like it I can send it back and just pay shipping.

 

[arcsnsparks98]

I have yet to see two very important words mentioned...lumen depreciation. MH lamps look awesome for 6 months or so and then their lumen output starts taking a ride down that steep slope that is the depreciation curve. So initial lumen output lasts about as long as the resale value of a new car bought at sticker price. That is why an LED with half the lumen output can match a MH lamp. When properly sized of course.

 

[Ragin Cajun]

I did a quick look at their web site and the replacement lamps require cooling fans.

RC

 

[Ragin Cajun]

Hubbell has some nice LED fixtures.

What type of ceiling do you have?

http://www.hubbelllighting.com/led/products/categories/industrial/highbay/

These put out a LOT of light but are of the "industrial" flavor.

http://www.prescolite.com/products/md8led/

This one puts out 12,000 lumens and is a lay-in.


I perrsonally am not a fan of screw-in replacement LED lights. Nor fans.

The comments regarding temperature are right on.

Good luck!

RC

 

[kwired]

No need to keep quiet... I mean, thats why we're all here isn't it? I welcome your input.

Can you please elaborate? One for one meaning lumens? Watts? Bulbs?

I do more machinery installs,troubleshooting and repairs. Lighting has always been the thorn in my side. So many options....

While I understand MH to be very effecent per watt, I think the point being focused on in this case is the effecency of an omni-directional bulb is a recessed can light application (down lighting). I'm led to beleive this is why an LED could work well in this case.

This is a nerve racking experiance for me as I am proposing an expensive change over and have flip flopped in my own mind several times. So by all means, please, explain your feelings on the subject.

Thanks Cajun

I am far from an expert at lighting design and have some similar confusion myself with some of these terms.

How are lumens wasted? Seems to me that is part of what reflectors, diffusers, and other luminaire components are all about - to direct the light where it is desired. Place same lamp in same place on just a pendant with no reflector, no diffuser or other optical equipment - then I can understand there will be wasted lumens. I can also understand there could still be some wasted lumens but it gets more complex determining them I would think. A particular flood light is going to be designed for maximum optimal operation at a specific distance from the area it is designed to light. Change that distance and you will effect that optimization at a specific point , but same amount of light is still emitted from the luminaire.

So even before the CFL's and LED's came out and made things more complicated, you still could get a difference in performance between different luminaires that utilized the exact same lamp because of optical component differences of the luminaires themselves.

 

[milemaker13]

yes, the new lamps do have a cooling fan bulit in. I agree that would concern me... except these come with a five year warranty. So if it goes out before then due to a dead fan, I should get a replacement.

And I will point out my main goal in this proposed change over to line voltage screw in lamps... Ease of repair. With the fixtures your proposed, which are probably awesome, I would still have to get up to the ceiling after 50k hours (5.7 yrs). Well, someone will have to :lol:

Changing to screw in LEDs I can remove the glass lense, allowing me to re-lamp using the long pole. SInce the light engine (ballast?) is included in the lamp, never have to get up there to replace components. I plan to fabricate a custom "soup can" that will securly grip the lamp, safely bring it down and back up, then easily un-grip. All a problem using the currectly avalible attachments.