"Ralph Mowery" wrote in message
. net...
My Malibu transformer is sold as 500W unit which is referring to the 12V
output. The label on my transformer says INPUT: 3.5A max @ 120VAC which
would calculate to be 420 Watts.
The OUTPUT is labeled: 500W total @ 12V, BUT it is really two 250W
outputs
or about 20.8A each output.
If the OP has 3 equal outputs of 200 Watts each then that would be 16.6
amps
each which would be reasonable for the 12ga low voltage wire they sell.
Kevin

Thats a good one, good for more watts out than the input wattage. The
trasnformer could not be more than about 90% efficiant so 380 watts should
be about the maximum output of the transfromer.

Just guessing but It may be that the stated output wattage is based on the
advertised wattage of the intended low voltage bulbs, which may or may not
be what they say, AND maybe with the cable voltage drop factored in, rather
than the actual transformer secondary wattage. The word 'nominal' is printed
somewhere on the label so that means it could be anything.... They give
examples on the label: Use ten 25W bulbs on each output etc. I know if you
don't have enough cable, 10'+ to the first connection, then the bulb will
burn out fast. Also if I am not about 50% loaded the bulbs burn out fast,
like in 2 or 3 weeks. As one bulb blows it makes things worse for the rest
and they blow faster etc.
I didn't mention that my box has a 125V timer motor that I assume is added
in as part of the input current but not the output current. That would make
things a little bit worse as far as the actual input/output wattage
comparison is concerned.
Kevin



The 120 volt circuit should be good to power atleast 2 of the transformers
if that is the only load on them. If there is some other load but not
much
he should still be ok with it.