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ParkerLawn
03-10-2007, 12:52 PM
Just now getting into lighting and have read several books and many hours on forums trying to learn what I can and am now giving it trial and error in the field. I just finished a system and have a question on my readings at fixtures. I have 3 different trans setup on the property but will just give you one scenario to see if I am correct on this. I have 4 runs on the one 600 wat trans and split them into approx. 100 watts per run on 12/2 with them installed in a loop runs back to trans. I have them set to 12v at the box and my nearest fixture to trans reads 11 and the furthest reads 10. Is the about right what I should expect in a voltage drop ont his run which is approx. 50-60 feet. House looks great at night and custoemr very happy but I am still learning and trying to understand.

bumper
03-10-2007, 08:58 PM
Terminology in different parts of country being what it is, not sure what you mean by "loop" is it a daisy chain? all lights strung on one run on the same 12/2 spliced in? You should be hitting near 11 volts at each fixture on each run. The variance you present 11 close to the transformer 10 farthest away will effect bulb life. Once one bulb goes the voltage will change on the other bulbs, the burnout rate will hasten after one bulb goes south. Some manufacturers rec. 11 for the longest life of the bulb and relative even burn rate, others will say give a .5 variance using 11 as the desired voltage. I think your 10 needs to bumped up but your 11 should stay where it is.

ParkerLawn
03-10-2007, 10:20 PM
So how do you bump the voltage to the furthest lamp and not affect the nearest lamp? I figure you will always have voltage drop on any run at your longest fixture? Am I wrong here?

Pro-Scapes
03-10-2007, 11:59 PM
different wiring methods... Alot of guys preffer a HUB or a T or other more evenly distributed methods. You speak nothing of the wattages or the wire lenght or number of fixtures.

bumper
03-11-2007, 01:14 AM
Like Billy mentioned, a hub or T will evenly distrubute your voltage to all your fixtures on the same run. All calculated with bulb wattage, type of wire and length of run. For you to raise the voltage on the last fixture would probably begin cutting into your profit. But at least you know what fixtures will be your trouble spots down the road.

bumper
03-12-2007, 07:23 PM
Just cuz I wanted to know what the loop is, I looked it up, pretty much a daisy chain with a loop :)

Pro-Scapes
03-12-2007, 09:13 PM
yes... thats all it is... A daisy chain fed from both elds. It can be useful but then again so can your toe nail clippings.

People abuse loops is the biggest problem I have seen. Electricians running 500ft with loops and installing way too many fixtures in line. Just goes to give low voltage lighting a bad name.

klkanders
03-12-2007, 10:07 PM
Hey Parker,
Did you happen to check the voltage coming from the outlet that the transformer is plugged into? If you are saying you have 11v at the first fixture it leads me to believe you are not getting a full 12v out of that 12v tap. Also is it just me thinking that on a 60' loop the voltage drop between fixtures shouldn't be much at all?

Also big differnce between loop an daisy chain. Daisy does not come back into trans. after it leaves like the loop. Daisy is a dead end road where first and last fixture will have voltage drop between them. Not saying you wont have voltage drop on loop wire because you will but it will be spread out between the fixtures.

Hope this helps!

Eden Lights
03-14-2007, 06:53 PM
Just cuz I wanted to know what the loop is, I looked it up, pretty much a daisy chain with a loop :)


Lollipop-A daisy chain with a loop at the end

Eden Lights
03-14-2007, 06:59 PM
yes... thats all it is... A daisy chain fed from both elds. It can be useful but then again so can your toe nail clippings.

People abuse loops is the biggest problem I have seen. Electricians running 500ft with loops and installing way too many fixtures in line. Just goes to give low voltage lighting a bad name.

Loops are great when lighting a deck, but as with everything else poor design and installation gives low voltage lighting a bad name.