help!! old lv lighting

[electricmanscott]

Trouble shooting old lighting system. Push button controls relay at fixture. Any tips?? All lights are not working.

 

[RICK NAPIER]

I have not seen a system like that in a long time. There was a central transformer that runs the system. Did you check it out? On one site I could not find out why the system had completely dropped out until I discovered that they installed a new sliding door and cut all the low voltage cables.

 

[Dennis Alwon]

If nothing is working I would also make sure the trany has power and check the output on the secondary side. It is very unlikely all the relays and switches don't work so I agree the trany seems to be the problem.

 

[electricmanscott]

24v tranny puts out 27v without load connected. With load connected it drops to 11v and gets burning hot. Time to go hunting

 

[al hildenbrand]

24v tranny puts out 27v without load connected. With load connected it drops to 11v and gets burning hot. Time to go hunting

Yup.

Sounds like a short on the LV side, maybe a coil. Isolate and locate.

 

[mivey]

I actually kind of liked these systems and wish they weren't considered old news. Maybe because they were sort of unique.

Happy hunting.

 

[electricmanscott]

Five hours, gallons of sweat, lots of fibreglass ingested, problem solved. Found the short. The last fixture in the loop. :roll:

 

[Dennis Alwon]

Five hours, gallons of sweat, lots of fibreglass ingested, problem solved. Found the short. The last fixture in the loop. :roll:

See you earned that $80.00 service call. Congrats:grin:

 

[SEO]

Five hours, gallons of sweat, lots of fibreglass ingested, problem solved. Found the short. The last fixture in the loop. :roll:

Ever stop to wonder how many times the problem is in the last item in the circuit?

 

[stickboy1375]

Five hours, gallons of sweat, lots of fibreglass ingested, problem solved. Found the short. The last fixture in the loop. :roll:

I always start in the middle.

 

[Dennis Alwon]

I always start in the middle.

Yeah that works until you have an even number of lights.

 

[Besoeker]

I always start in the middle.

Yes logical, I suppose. If there were say 32 fixtures, you could locate the faulty unit by eliminating all others in 5 steps instead of up to 31.
But then there are the practicalities. In the absence of any better clues, most of us would check what's quickest and easiest first.

 

[al hildenbrand]

Ever stop to wonder how many times the problem is in the last item in the circuit?

I've observed that Murphy's Law rules.

I always start in the middle.

I've observed that it doesn't matter. . . [irony] with the middle as the first, there is still a "last". [/irony]

Murphy's Extended Law: If a series of events can go wrong, they will do so in the worst possible sequence.

 

[electricmanscott]

I always start in the middle.

Me too, if I can tell where that is.

 

[jeremysterling]

Five hours, gallons of sweat, lots of fibreglass ingested, problem solved. Found the short. The last fixture in the loop. :roll:

I'm impressed. It's been 105? here and I have to work at least 10 hours to sweat 2 gallons.:grin:

Troubleshooting school says 2 independent faults are a rare occurrence. I've seen the opposite many times. Instead of the middle of the string, I would have started at the lum with the burned out lamp!:roll:

 

[stickboy1375]

Me too, if I can tell where that is.

I was only being funny Scott, I know you know better.