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[ma876]

hi this might seem like a silly question but what does VA stand for on transformers? I`m guessing its the output rating, if so what would a 150va transformer discharge in the form of amps, watts?

[kbrownie]

HI ma876,
VA stands for the maxmium Volt Amp Rating This is the sum of Volts X Amps
so say that your mains voltage was 230V then the current would be 0.652A. (230x0.652=150VA)
Regards
KB

[ma876]

thanks kb, how would i work out how many 20w lamps i could run from a 150va transformer?

[sparx]

seven!
150 divided by 20 = 7.5 & as you can't buy half a lamp it's 7 with a bit to spare!,
VA is as KB says Volts X amps = watts for a purely resistive load, if inductive such as motors transformers ect, then power factor reduces actual power available which is why gen. sets have 2 ratings watts & VA.
Makers always advertise in VA as numbers more impressive, a bit like Americam horse power, only pony power to our way of measuring!!!
regards SPARX

[ma876]

Thanx very much