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i'm in the market for a step-down transformer to work with my heating blanket i found this on e-bay.

Any thoughts about it, will it work, the blanket is rated 800w. I'm very sceptical of this, but the price is certainly right, compared to other products i've seen.

Thanks,

Frank

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Frank

I dunno... Contact LMI or Stew-Mac... they sell the proper converters.

That site looked very goofy to me.

Mike

yes, seemed goofy to me too, getting a decent converter from the states would not be worth it for the price of shipping(norway), should have checked around a bit more before i bought the blanket it seems....

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Frank

Hi Frank -

I don't know what this device is for certain, but I suspect it is simpy a diode (rectifier) that blocks the AC line voltage during half the cycle. So you end up with the maximum voltage across the heating blanket being half the 220V. If all that is the case, the blanket should work ok. You may have problems with using a router speed control or similar to adjust the heat, though.

Hopefully others will chime in here who know exactly what the little box is. For sure, it is not a transfomer, which for this kind of power would be much larger, much heavier, and pricey!

Tom


Edit - Did a google search - look here [url][/http://www.220converters.com/store/p/121-1600-Watts-Travel-Voltage-Converter.html]

Looks like your converter - notice the warning about 30 minutes maximum use time

Tom

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Tom Barton

Blocking half the cycle won't change the voltage as it will still be 220v. Just pulsating 220 v + or 220v -.
I don't know what that box is but is a small transformer with 2 to 1 windings that costly ? Too bad you didn't buy 2 blankets then you could have wired them in series and used the 220v. With the blanket it won't matter that you are at 50 cycles instead of our 60 cycles. You just need to step the voltage down.

Yup, same peak voltage, of course (long day...). This will reduce the average power to the blanket by a factor of two, I'm pretty sure. But the high peak voltage and current will kill the blanket, and probably present a safety hazard.

Tom

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Tom Barton

Hmm, If i get a second blanket and wire them in series can i use the heat controller?
I got the blanket+controller combo from john hall.

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Frank

Please, when it comes to AC current, buy proper equipment. If you are not sure what is going on, then stay away from it. LMI or Stew-Mac (can't remember which) posts stern warnings about this.

Mike

Frank,
might even be worth checking with John Hall.
I and several other builders in Israel, got 110V blankets from John.
maybe, since it seems your blanket is still unused, you could work something out.

just a though...

Udi.

In work we have a lot of 110v tools from the olden days when they said that we couldn't use 240 for safety reasons.

I have a transformer that weighs about the same as a car battery and the 110v tools plug into it. 1/3 sheet sander, strip bender etc.

the problem is going to be shipping if you buy one as they are HEAVY.

try a pro tool store, they might still stock them

here y'go this sort of thing, you should be able to get one locally.

http://www.ryness.co.uk/SearchResults.aspx?txtSearch=110%20volt

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