I am installing a low voltage lighting system (Malibu) around the yard for the second time. Previously, I had four different transformers, but this time I want to use a large, single one, and use the existing buried wire by just connecting all into one circuit. However, this would mean a total distance of approx. 250-300 ft, using 16 gauge wire. CAN I DO THIS SAFELY? I know they say it isn't good, but is it truly dangerous or will the lights at the end of the line just be a bit dim? Please help. Thanks.
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The length isn't a safety problem as far as I know. What is the load? Without knowing that, we can't determine if the cable will be overloaded. So please post the total wattage & the operating voltage.
The operating voltage is 12 volts and so the cable is 12 volt cable. The transformer i will be using is 300W, but I will have a load of somewhere between 120 and ~180W, depending on the type of spotlights i add. It might also be wise for me to get a smaller, 150W transformer and then limit the load to 150W. With this info, do you think it would be safe to run a 16 gauge cable for 250-300 ft? Thanks.
You will have some voltage drop and the ****hest lights will be noticeably dim. It will help even if you can replace some of the run with 10 gauge.
You'll probably have to strike a match to see if the last light on the string is lit. Even #10 might not be big enough.
Also, if you go to 180 watts of load (15 amps) this is more of a load than 16 guage can safely handle. #14 house wire is only good for 15 amps & you are thinking of putting a possible 15 amp load on a smaller wire.
Just because it is low voltage, don't be lulled into thinking it can't pose a safety hazard.
Tom
Keg........
What do you mean by:
"......by just connecting all into one circuit." ?
You can do this safely by having multiple branches from the same transformer......(were all the old transformers mounted in the same location?)
The problem occurs when you try to put all the fixtures on a single run............
Tom O
Where are you coming from? The load is 180 watts. Watts/voltage = amps
My calculation shows 1.5 amps. Just hook it up and try it. You may have voltage drop and the last couple lights dimmer, but then again you may not.
Bob jr,
The voltage is 12. Thus 180w / 12v = 15 amps. This would be the total load on the x-fmer and the wire at the beginning of the run. Unless all of the lights are at the end of this long run, the load on the wire at the end of the run will not be 15 amps.
The voltage is 12. Thus 180w / 12v = 15 amps. This would be the total load on the x-fmer and the wire at the beginning of the run. Unless all of the lights are at the end of this long run, the load on the wire at the end of the run will not be 15 amps.
There is a way to do a detailed voltage drop calculation byt determining the "load center" & it is fairly accurate. To perform the calculation, we would need to know the distance from the transformer to each fixture.
As previously stated, I believe that #16 wire is too small from a safety standpoint .
Tom
