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Dim LV fixture #66646
06/10/06 10:56 PM
06/10/06 10:56 PM
trobb  Offline OP
Joined: Jun 2006
Posts: 110
Iowa City, IA
I was at work today (over the summer I'm working at an ice cream store) and I noticed that the LV (MR16) fixture (an open bottom recessed can) over the waffle irons was giving only 10% (roughly) of it's normal light output. All the other fixtures on the switch and circuit are operating normally. Two questions result: could the steam given off by the waffle iron be affecting the output (perhaps shorting the HV leads on the transformer), and are there any suggestions on fixes for this problem? Thanks y'all.

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Re: Dim LV fixture #66647
06/11/06 02:31 AM
06/11/06 02:31 AM
briselec  Offline
Joined: Dec 2005
Posts: 141
Brisbane, Australia
changing the lamp would be a good start.

Re: Dim LV fixture #66648
06/11/06 11:31 AM
06/11/06 11:31 AM
renosteinke  Offline
Cat Servant
Joined: Jan 2005
Posts: 5,316
Blue Collar Country
Assuming thay a new bulb will also be just as dim.... then the problem is likely in the wiring.

Since it is just the one light, the best guess would be a bad splice or connection.

Low voltage lights are powered by transformers with very limited power output. Other causes of dim light(s) I have found have included:
-too much voltage drop, caused by too long of a wire;
-too many lights n the transformer; and,
-different circuits (some power supplies have more than one output circuit) interconnected.

Re: Dim LV fixture #66649
06/11/06 05:34 PM
06/11/06 05:34 PM
trobb  Offline OP
Joined: Jun 2006
Posts: 110
Iowa City, IA
Thanks for the help. I went to try and change the lamp this morning, and it turns out the (inline) connector between the lamp housing and the LV transformer was arcing (there is a lead of wires, then a connector, then more wire; no idea why). At least, that's my guess based on how the connector was showing visible signs of over-heating-- brown, crumbling, and slight distortion (one piece fell off in my hand as I went to break the connection). The connector will be replaced, but I want to figure out why this happened and how to prevent it from happening again. Not really necessary to keep replying, but I do appreciate you guys helping me figure out where to start.

Re: Dim LV fixture #66650
06/11/06 07:38 PM
06/11/06 07:38 PM
HLCbuild  Offline
Joined: Dec 2004
Posts: 209
Herndon,Va USA
I believe the connector is to make it easy to change the low-voltage socket. I usually keep 4 or 5 sockets with me as I find many problems with them. Seems the halogen lights burn real hot and when the connection gets weak, the wire fries.

Re: Dim LV fixture #66651
06/11/06 09:28 PM
06/11/06 09:28 PM
e57  Offline
Joined: May 2003
Posts: 2,876
"why this happened and how to prevent it from happening again"

Tight - solid, and clean connections.

The amperage of the connections on the low voltage side of the transformer are 10X's what they are on the line voltage side. (.417 vs. 4.17) A loose connection will heat up, arching more and more over time and eventually fail.

Mark Heller
"Well - I oughta....." -Jackie Gleason
Re: Dim LV fixture #66652
06/11/06 09:53 PM
06/11/06 09:53 PM
trobb  Offline OP
Joined: Jun 2006
Posts: 110
Iowa City, IA
That's the funny part-- the connector that failed was pre-installed in the fixture. Could be when it was installed we forgot to check internal connections, though (making a mental note for next time).


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