Electricity pros?

[Usha Starchild]

Just a quick question because I cant find a good electricity forum.

I have an older Amplifier(Receiver) a Pioneer VSX-D509S, I'm gonna guess its about 9 years old. I bought it before I went to China and never used it. I got some of my stuff shipped over here and this was one of the items.

Now the problem.

China uses 220v instead of 110, so I need to buy a transformer(voltage converter). I'm just not sure how many WATTS I should buy. My Amp does not say how many WATTS it uses.

It has
AC 120V 60Hz
350VA

I took electronics in High School but forget all the formulas, I remember VoltsxAmps = Watts? What are VA and how can I use them to figure out how large of a transformer to buy?

Note: Id go buy a new receiver here but they rip China off on component audio, for the lowest price Yamaha over here its 7000rmb (1000 dollars almost) and that same model is like 200 bucks back home. Anything considered luxury is jacked up in price. as for the transformers they double in price over 300W. They want 100bucks for a 500w transformer.

[Usha Starchild]

volt-ampere
Volt-ampere (VA) is a measurement of power in a direct current ( DC ) electrical circuit. The VA specification is also used in alternating current ( AC ) circuits, but it is less precise in this application, because it represents apparent power , which often differs from true power .

In a DC circuit, 1 VA is the equivalent of one watt (1 W). The power, P (in watts) in a DC circuit is equal to the product of the voltage V (in volt s) and the current I (in ampere s):

P = VI

In an AC circuit, power and VA mean the same thing only when there is no reactance . Reactance is introduced when a circuit contains an inductor or capacitor . Because most AC circuits contain reactance, the VA figure is greater than the actual dissipated or delivered power in watts. This can cause confusion in specifications for power supplies. For example, a supply might be rated at 600 VA. This does not mean it can deliver 600 watts, unless the equipment is reactance-free. In real life, the true wattage rating of a power supply is 1/2 to 2/3 of the VA rating.

When purchasing a power source such as an uninterruptible power supply ( UPS ) for use with electronic equipment (including computers, monitors, and other peripherals), be sure the VA specifications for the equipment are used when determining the minimum ratings for the power supply. The VA figure is nominally 1.67 times (167 percent of) the power consumption in watts. Alternatively, you can multiply the VA rating of the power supply by 0.6 (60 percent) to get a good idea of its power-delivering capability in watts.

So going by that it says my 210watts about? But is that how much the system draws or pushes out? I dont want a transformer fire. ;p

[mylek]

For what it's worth the power supply on my PC will take from 100-240 volts AC which means it should work just fine in most countries. Are you sure you even need a transformer?

AC 120V 60Hz
350VA

US power is already 120v 60Hz in household outlets. You should be able to just plug it in unless they hacked the power supply without relabeling it.

[dandrools]

I think he's saying he has an amplifier made to run on US power but he's in China, thus the dilemma.

VA just means Volt-Amps, which is the same thing as saying Watts.

So 350W times whatever multiplier they say, so yeah 210 is probably correct.

[mylek]

For some reason I read it that he was coming to the US from China. Makes sense now.

[Usha Starchild]

Originally Posted by dandrools

I think he's saying he has an amplifier made to run on US power but he's in China, thus the dilemma.

VA just means Volt-Amps, which is the same thing as saying Watts.

So 350W times whatever multiplier they say, so yeah 210 is probably correct.

Yeah, they say it pushes out 210W aprox. But does it still draw 350W? Should I be looking at a 350watt transformer or 250? The price dif is a lot.

[Ara]

I downloaded the manual of it and there it says (Specifications section) it has a power consumption of 250W.

[Usha Starchild]

Thanks guys +nets to you two

[Gauss]

"VA" is the unit for complex power. Since you're not looking for a lecture, I'll just say that I interpret 350VA to mean that you need to look to supply 350W (which is of course different than what Ara claims was in the manual). Without going into it, your need to supply 350W for your amplifier to use 250W.

[Lenaldo]

Originally Posted by Gauss

"VA" is the unit for complex power. Since you're not looking for a lecture, I'll just say that I interpret 350VA to mean that you need to look to supply 350W (which is of course different than what Ara claims was in the manual).

THERE'S NO SUCH THING AS IMAGINARY POWER! IF IT WAS IMAGINARY, IT WOULDNT BE REAL. OMG MY BRAIN

[Usha Starchild]

Originally Posted by Gauss

"VA" is the unit for complex power. Since you're not looking for a lecture, I'll just say that I interpret 350VA to mean that you need to look to supply 350W (which is of course different than what Ara claims was in the manual). Without going into it, your need to supply 350W for your amplifier to use 250W.

AC and Resistance right?

[Ara]

Depending on how powerful your Amp + Speakers are, and how loud you wanna hear, you can probably get away with much less W anyway. I once took a measure of my Denon @ 5.1 and normal listening volume, and it was using 60W IIRC.

[Gauss]

Originally Posted by Ara

Depending on how powerful your Amp + Speakers are, and how loud you wanna hear, you can probably get away with much less W anyway. I once took a measure of my Denon @ 5.1 and normal listening volume, and it was using 60W IIRC.

This is true. It's the lowest frequencies that require the most power to produce, and so if you don't fancy ghetto bass that rattles your house then perhaps a smaller transformer would be fine.