Replacing MR16 Halogen with LED lamp - Contractor Talk - Professional Construction and Remodeling Forum

raecampus · 11-24-2007, 05:28 PM

Gentelmen

I need some advice on switching out MR16 Halogens
on a low voltage outdoor system with MR16 LEDs for a Subdivision.

They are utilizing Kichler transformers, fixtures.

I realize the MR16 LEDs are pricey and there are other concerns. I have read where some electronic transformers
are not compatble with LEDs as the transformers require a minimum load which LEDS may not meet. Would I need a different type of transformer or perhaps an LED driver? I have also read where LEDS have a minimum ambient temperature tolerance. Most of the outdoor lighting fixtures do not allow for adequate air flow.

I would appreciate any direction on this as LEDS are coming on very strong in all segments of lighting, signage,video, and professional staging applications.

I was at the LDI (Lighting Dimensions International)convention in Orlando in Nov. 07, and was totally amazed!! Sparsley a halogen, zenon, florescent, or other!!

LEDS are here my friends, how to retrofit?

Thanks much comrades!

Randy in Orlando

James Solecki · 11-24-2007, 08:49 PM

Quote:

Originally Posted by raecampus

Gentelmen

I need some advice on switching out MR16 Halogens
on a low voltage outdoor system with MR16 LEDs for a Subdivision.

They are utilizing Kichler transformers, fixtures.

I realize the MR16 LEDs are pricey and there are other concerns. I have read where some electronic transformers
are not compatble with LEDs as the transformers require a minimum load which LEDS may not meet. Would I need a different type of transformer or perhaps an LED driver? I have also read where LEDS have a minimum ambient temperature tolerance. Most of the outdoor lighting fixtures do not allow for adequate air flow.

I would appreciate any direction on this as LEDS are coming on very strong in all segments of lighting, signage,video, and professional staging applications.

I was at the LDI (Lighting Dimensions International)convention in Orlando in Nov. 07, and was totally amazed!! Sparsley a halogen, zenon, florescent, or other!!

LEDS are here my friends, how to retrofit?

Thanks much comrades!

Randy in Orlando

Sounds like you have a pretty good understanding of some of the bigger issues of using LED lamps already.

There are a plethora of power LED lamp modules on the market now. I have tested many here at my shop and found only a couple that come close to the intensity, colour and beam spread of a 20W BAB Halogen MR16 lamp. So far I have found none that emulate the light from a 35W FMW MR16.

Retrofitting a MR16 LED module into a standard landscape lighting fixture is pretty easy. They perform well with the magnetic (inductive) transformers that are most common in LV lighting systems and the better LED modules have on board power management circuits that allow you to send them wide range of voltages.

Heat management is a critcal issue with power LED modules. They do create heat and that heat is essentially toxic to their long term operation. That being said, installing LED modules in top quality brass, bronze, or copper fixtures is an excellent start, as the fixtures themselves are great heat sinks. Also pick fixtures that have a lot of airspace inside. I would be hesitant to install power LED lamps in any form or plastic or composite fixture.... I dont think they would shed the heat well enough.

Finally... be very careful of the colour of the LEDs you select. You really have to test most LED lamps up against halogens... do not just take their colour claims at face value. Nothing looks worse (im my opinion) then a bunch of path and deck lights using xenon and halogen (at 2700k to 3200k) mixed in with some 4000k to 5000k LED lamps. looks like a dogs breakfast to me.

Have a great day.

buildenterprise · 12-14-2007, 09:47 PM

I just installed a bunch of post top lights on a deck we just finished. I swapped out the 18 watt 1156 incandescent bulbs for 18 LED equivalents. The LED bulbs use .07 watts each! And you're right about the transformer needing a minimum of 20 watts load to operate properly. I used a cordless phone transformer plug, works like a charm!

James Solecki · 12-15-2007, 10:23 AM

Quote:

Originally Posted by buildenterprise

I just installed a bunch of post top lights on a deck we just finished. I swapped out the 18 watt 1156 incandescent bulbs for 18 LED equivalents. The LED bulbs use .07 watts each! And you're right about the transformer needing a minimum of 20 watts load to operate properly. I used a cordless phone transformer plug, works like a charm!

Would you tell us exactly what type of LED lamp you used?

I am not familiar with any Single Contact Bayonett LED lamp that will operate on 12volts AC as supplied from a Listed LV Outdoor Lighting transformer. The only 12V SCB LED lamps that I have found on the market are 12V DC and built for the auto market for use in tail lights etc.

You still have to be very aware of code and certifications. I don't think that using a indoor cordless phone transformer as your power source is the way to go. You might have service problems with that installation in the future.

Have a great day.

buildenterprise · 12-15-2007, 12:30 PM

Quote:

Originally Posted by James Solecki

Would you tell us exactly what type of LED lamp you used?

I am not familiar with any Single Contact Bayonett LED lamp that will operate on 12volts AC as supplied from a Listed LV Outdoor Lighting transformer. The only 12V SCB LED lamps that I have found on the market are 12V DC and built for the auto market for use in tail lights etc.

You still have to be very aware of code and certifications. I don't think that using a indoor cordless phone transformer as your power source is the way to go. You might have service problems with that installation in the future.

Have a great day.

The incandescent bulbs I took out of the lights are marked "1156", which is the standard 18 watt, 12 volt single contact bayonet mount auto bulb. I replaced them with 1156 SCB LED equivalents. So you're telling me there are two types of 1156 bulbs, 12vdc and 12vac?

As for the cordless phone transformer, it was part of the kit of LED riser lights I purchased for the job. The output voltage and amperage numbers are quite sufficient to handle the led bulbs.

James Solecki · 12-15-2007, 12:55 PM

Quote:

Originally Posted by buildenterprise

The incandescent bulbs I took out of the lights are marked "1156", which is the standard 18 watt, 12 volt single contact bayonet mount auto bulb. I replaced them with 1156 SCB LED equivalents. So you're telling me there are two types of 1156 bulbs, 12vdc and 12vac?

Not exactly....
The standard 1156 incandescent lamp will operate on either 12Vac or 12Vdc. Professional Quality Low Voltage Lighting Systems operate at or near 12V AC current, not DC. The LED lamps you installed are most probably DC units. Check the label on the transformer that you used under "Output".

As for the cordless phone transformer, it was part of the kit of LED riser lights I purchased for the job. The output voltage and amperage numbers are quite sufficient to handle the led bulbs.

I am sure the transformer supplied is capable of providing enough volts & amps to do the job. My concern here is that it is probably not rated for outdoor use. The housing and the output wire from that plug in transformer will not stand up to the outdoor environment in the long run, and you have just installed a transformer in an application for which it is technically not intended. These are professional "no-no's".

buildenterprise · 12-15-2007, 02:05 PM

Quote:

Originally Posted by James Solecki

I am sure the transformer supplied is capable of providing enough volts & amps to do the job. My concern here is that it is probably not rated for outdoor use. The housing and the output wire from that plug in transformer will not stand up to the outdoor environment in the long run, and you have just installed a transformer in an application for which it is technically not intended. These are professional "no-no's".

I know better than to install these outside.
The 16 gauge wire was run through conduit into the crawlspace, where I installed the GFCI outlet on a floor joist that the transformers are plugged into. They are not exposed to any outside elements. The output is 10.8vdc.