Low voltage xformer

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  #1  
Old 09-18-07, 08:25 PM
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Low voltage xformer

Can anyone tell me (other than the obvious because its not tested for etc.) why you can't put a landscape lighting transformer indoors??

I've had an 88 watt intermatic at my panel(in basement) for 4 years with no problems. It died the other day and i want to replace it with a 300 watt one but noticed whilst looking at them at the store that they said do not install indoors.

Now logically I can't think of why I can't other than heat dissapation. It seems that everyone has more dangerous items installed in their homes other than transformers.

What gives.
 
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  #2  
Old 09-19-07, 06:19 AM
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I can't imagine any problem with it as long as you make sure of the obvious (don't install it behind curtains, don't enclose in a non-vented enclosure, etc). They don't tend to get very hot, so I can't see any issue with it. I'm sure others will chime in.
 
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Old 09-19-07, 08:35 AM
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JOHNJOHN, you already correctly guessed the answer to your own question.
 
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Old 09-19-07, 08:42 AM
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Outdoor transformers are listed under a different UL standard than indoor transformers, which means they are tested to different safety levels. I don't know specifically, but I would guess there are at least two distinctions: heat dissipation, as you suspect; and burning characteristics. The outdoor transformers may produce a greater amount of smoke and hazardous fumes when burned that would violate indoor fire codes.

> It seems that everyone has more dangerous items installed
> in their homes other than transformers.

I've seen a number of these lighting transformers installed inside garages, closed porches, and homes. I don't think it's the end of world, but there probably is a good reason they're listed for outdoor use only.
 
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Old 09-19-07, 09:42 AM
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Don't the manufacturers pay UL for testing and Listing? Maybe just cheaper to pay for the single rating then the dual.

I have wondered too though. I once changed a planned installation for a customer because of it. Just didn't want to take the chance on a customer install. It meant though the customer had to have a outside receptacle installed. Putting it in the pool house as originally planed would have been cheaper. Maybe someone should write Malibu or UL. <G>
 
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Old 09-19-07, 10:19 AM
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I think that ray2047 has hit the nail on the head. The almighty dollar controls much of what we see and do. Whether it;s the testing fee or not, I
cannot say. Perhaps a certain component part would cost more to get the indoor rating, or perhaps it is the testing fee.
 
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Old 09-19-07, 01:10 PM
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Ok thanks everyone, I will be mounting it on the same backboard as my panel and there is plenty of air flow around it and no combustables near it so I feel comfortable doing this.

And hey if does put of a little more toxins while on fire than so be it. I've injested worse LOL.
 
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Old 09-20-07, 08:22 PM
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Low Voltage Transformer

[QUOTE=JOHNJOHN;1231497]Can anyone tell me (other than the obvious because its not tested for etc.) why you can't put a landscape lighting transformer indoors??

Requirments for Landscape lighting are driven by article 411 of the NEC and transformers are listed under UL1838. Malibu products are NOT listed for indoor use (which is required). Additioinally the wiring method would need to pass thru the structure to get to the outside. Lanscape wiring does not meet NEC requirements for class 1 wiring methods.

I was formerly Drector of Engineering responsible for the Malibu products. I have seen more than one fire investigation for people who didn't think this would be a problem... then combined with other mistakes they burned their homes.

You should take the unit outside as the instructions indicated.
 
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Old 09-20-07, 08:26 PM
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Originally Posted by racraft View Post
I think that ray2047 has hit the nail on the head. The almighty dollar controls much of what we see and do. Whether it;s the testing fee or not, I
cannot say. Perhaps a certain component part would cost more to get the indoor rating, or perhaps it is the testing fee.
Being the individual responsible for the listing of these products, I can assure you it was not a way to save money at UL/CSA. There are in fact very different design and construction requirements when you want product suitable for indoor installations.
 
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Old 09-20-07, 09:31 PM
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Originally Posted by Yogi01 View Post
Being the individual responsible for the listing of these products, I can assure you it was not a way to save money at UL/CSA. There are in fact very different design and construction requirements when you want product suitable for indoor installations.
I realize a detailed discussion of these requirements is outside the scope of this forum but can you give us the Cliff Notes version?

I once installed an electric gate opener that ran from a battery which in turn had its charge maintained by a low voltage plug-in transformer. There were no restrictions imposed by the manufacturer on mounting inside or running low voltage wire through the wall. Then there are sprinkler controllers which are routinely mounted inside but have low voltage transformer with wires running through the wall. It seems Malibu is more the exception.
 
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Old 09-20-07, 11:40 PM
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I'm not about to write for Yogi01 but in the cases that Ray mentions I think the transformer/power supply/battery charger probably meets the requirements for either Class 2 or Class 3 circuits, both of which severely limit the current to far less than what a landscape lighting transformer supplies.
 
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Old 09-21-07, 09:25 AM
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Originally Posted by furd View Post
I'm not about to write for Yogi01 but in the cases that Ray mentions I think the transformer/power supply/battery charger probably meets the requirements for either Class 2 or Class 3 circuits, both of which severely limit the current to far less than what a landscape lighting transformer supplies.
Makes sense however I wonder from a practical point rather then code if a transformer fastened to old dried out wood siding is any less of a fire hazard Then one hung on Sheetrock inside.
 
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Old 09-21-07, 09:43 PM
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Originally Posted by ray2047 View Post
Makes sense however I wonder from a practical point rather then code if a transformer fastened to old dried out wood siding is any less of a fire hazard Then one hung on Sheetrock inside.
Exactly! I'm not completely incompetent. If I can't make the thing safe to be inside then it won't be safe on the outside wall of my house period
 
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Old 09-21-07, 09:53 PM
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Cya

Listed for 1 use ,cheaper.
put it inside , OK.
They won't tell you . Liability.

Less $ on lawyers.

Thats the reason.
 
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Old 09-22-07, 07:29 AM
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Good discussion here. Good input from the Malibu engineer. I am surprised at how many still say "screw it, I'm putting it inside." If you ever have a fire, for any reason, your insurance company inspects the fire scene. They find that transformer, and your up bleep creek.

UL listing does drive many decisions. I once worked for a company making telephone answereing machines, cordless phones, etc. All of these are powered from the wall cube, rather than direct plug in to the AC line. This way, you can just outsource a UL listed cube, and the basic machine does not have to be UL electrical listed. Not only does the UL testing cost a lot of money ( not a big deal to a big company, but imporant to a smaller company line ours) but the device itself has to be made different. Certain internal components must them selves be UL ( $$$) but various aspects of the electrical and mechanical design will be more expensive. This is why indoor sprinkler controllers are commonly powered from the wall cube. Outdoor units more commonly have to be hard wired to facilitate waterproof installation. They tend to be quite a bit more expensive.

As to the comment about the wood siding, a fire starting on the exterior siding will probably be less damaging, not spread so fast, and certainly be less life threatening than one starting inside somewhere. We can complain about the big brother syndrome, or we can be very thankful for the very positive aspects of the government codes and regulations which protect our lives and property. The recent toothpaste with antifreeze, tainted fish, and lead toys scandals from CHINA are very serious examples of what happens when one government (China) has no standards and another government (US) fails to come to grip with the import scandals.
 
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Old 09-22-07, 08:52 AM
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#If you ever have a fire, for any reason,#

..and they can't find the cause.... They claim electrical anyway. Easy out sometimes.


(I've heard the discusions )
 
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Old 09-24-07, 07:14 PM
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I was planning on mounting one in my garage wall it is a wide open space that gets plently of air flow. how hot do these transformers get?
 
  #18  
Old 09-24-07, 07:23 PM
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Your insurance will pay even if you do something stupid, as long as you do it. Just as long as you were not intending to start a fire...

Fire investigators do NOT list a fire as electrical if they can't determine the cause. They list it as undetermined.
 
  #19  
Old 09-25-07, 08:27 AM
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Everybody should get to choose the risk level that they want for themselves. If you want, you can take the attitude that "I'm going to do this unless you can prove to me that I'll die in the next ten minutes if I do."

it's a little trickier if you're also choosing the risk level for your family, your neighbors, and future owners. That's why we have codes.
 
  #20  
Old 09-25-07, 05:55 PM
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So the issue is the heat that the transformer produces, correct? The heat is what makes them unsafe?
 
  #21  
Old 09-25-07, 08:12 PM
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Originally Posted by lbphathead19 View Post
So the issue is the heat that the transformer produces, correct? The heat is what makes them unsafe?
I'm starting to wonder now.
 
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