Low voltage transformers

robbie59

Does a 120v to 12v 600w low voltage transformer use the same amount of KWPH regardless if there is lights hooked up to it or not?

I ask because I am looking at the option of buying 12v rope lighting vs. 120v.

I have a 600 watt transformer from Home Depot that I'd like to use and keep everything on the 12v system.

I just dont want to power up a 600 watt transformer to only use less than 100 watts.

nap

no. there is a very low level of consumption of power with no load on the secondary of the transformer.
Other than those losses, the power input is directly proportional to the power output.

robbie59

So that hummmming noise is not 600 watts of power getting sucked out of my electric bill? Only draws measurable power if I have lights hooked up to the line right?

nap

the power is measurable but it is only a fraction (small fraction) of the power that can be transferred through the transformer.

You can always put a switch on the line (house voltage) side of the transformer so there are no losses when not being used at all.

robbie59

Thanks, I have a switch but I was curious to know if I was using too big of a transformer to power a small amount of lights. If the draw is the same as the consumption of watts per light, Im ok with that

Thanks