wiring low voltage lights

[carlos31]

Can anyone provide a sanity check for 12v lighting. I will use the hayward colorLogic lights, 3 pool size and 1 spa size. The large lights need 50 watts each and the spa light needs 25 watts. The distances to the Intermatic PX300 transformer are 70, 50, 30 and 30 feet. I was going to home run all the lines and the ground wires to a junction box under the transformer then to the transformer. I was wondering if its actually better for the junction box to be closer to the lights or the transformer? Closer to the lights will be difficult in my situation.

Hayward recommends not exceeding 50 feet but offer lights with 100 foot cords!!!!! Since I am not a pro this mixed messge stuff really confuses me.


Thanks,

 

[JasonLion]

With low voltage lighting there can be a significant voltage drop in the wire as the wire gets longer. If there is too much voltage drop the light will not function correctly. You can compensate for this by setting the transformer to a higher voltage. I believe that the PX300 is adjustable to 12, 13, or 14 volts.

The chart I saw in the ColorLogic manual (near the very end) said that 12v is good up to 90 feet and beyond that you can switch to 13v (to 150 feet). Remember, that is the actual wire length, which is probably going to be noticeably longer than the straight line above ground distance.

You can put the junction box any where that is convenient. If it is far from the transformer you might want to use a heaver gauge of wire from the transformer to the junction box.