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Voltage question

 Would a component from Japan that is rated 100 volts be safe to use here on 110-120 volts, without some type of transformer or the like?  TIA  Mike


winoguy17
elliottbnewcombjr
5,248 posts
 
easy, amazon prime, $30. have it tomorrow.

https://www.amazon.com/VCT-VT-200J-Japanese-Transformer-Converts/dp/B081TLK87S/ref=asc_df_B004S2COIC/?tag=hyprod-20&linkCode=df0&hvadid=226131567976&hvpos=&hvnetw=g&hvrand=15901971708719460343&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9003512&hvtargid=pla-390921810426&th=1

they have several, they vary according to the amount of watts the device draws. Voltage must match, and watts simply have to be enough for the device(s) it feeds, CD player is not gonna need more than this 100 watt version..

A device will only draw what it needs, like a 60 watt bulb draws less from a line rated for much much more.

Volts are volts, i.e. Apple's 5 volt chargers. the amperage is low or high (amperage is relative to watts), so they keep raising the needed amperage so you need to keep on buying new adapters. And, they keep changing the connector types, the ........


gs5556
1,218 posts
 
Stepping down the voltage is the correct solution. Running it at 120 volts can cause problems... for example if a secondary voltage somewhere inside the unit is, say, 34 volts and there are 35 volt capacitors, then 120 volts on the primary will increase the secondary voltage above the rating of the capacitors and...poof. So unless you are dead sure about the voltage ratings of the parts inside, step down the voltage to where it is supposed to be. Simple physics, not misinformation.
heaudio123
689 posts
 
If it has a switch mode power supply, odds are it will be okay at 120/60Hz, though if truly designed for 100V only (rare) it could have issues with component tolerances and fail early.  If it has a linear supply, you could overheat things.
w.r.t. this post below, odds are it was built with universal 100-240VAC switch mode power suppl(ies). It is sensitive, but would likely use off the shelf supplies.

millercarbon3,254 posts03-02-2020 3:02amJust to give you all some idea how absurd it is to think a few volts matters, I once ran a lithotripsy machine designed for 240 on 120. For you mathlexic types that's like half the voltage. That's a complex and highly computerized machine that generates shock waves that break kidney stones. Its a lot of power, precision, and an incredible amount of sensitive electronics. More pumps, motors, servos, microprocessors, transformers and high voltage power supplies (in excess of 60kV) than you can shake a stick at. You would think the thing wouldn't even run, or at least would throw error codes, or work but weakly, anything but what happened, which was nothing. Worked absolutely fine. Didn't even know about the voltage until after the fact.

The disconnect from reality, misinformation, and nervous nonsense surrounding all things electrical is simply off the charts.

erik_squires
15,899 posts
 
Get the step-down transformer unless you have a smart power supply.

The way to tell is to read the requirements right off the device. If it says 100V and not 100-240V or something like that, you need the STD.
uberwaltz's avatar
uberwaltz
13,381 posts
 
Just to throw this out there.
I once ignored the 100v only and ran a DVD player on my 120v line thinking  it would be fine only 20% over volt.
Sure it worked just fine... For about 2 months when it then went up in a big poof of smoke.
Sure it was not major but I could not be bothered to even investigate.
Lesson learned I use stepdown on both my Japanese 100v TT now.
👍👍👍 Ymmv.
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