208 V single phase?

T. J.

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I recently acquired a muffle furnace in an auction. The nameplate specifies 208 volt single phase input. Am I going to fry it if I use standard 240 volt input? If so, is there an economical way to convert 240v to 208v?

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Most US homes have 220V. I'd bet it would be fine. You could use a suitably rated variac to adjust the voltage.
 
If you use 220v your current ( amps ) will drop a bit. I wouldn't worry about it
 
If you use 220v your current ( amps ) will drop a bit. I wouldn't worry about it
If it is a resistance heater, which it appears to be, the amps will not drop, they will go up by the ratio of the voltages. And the heat output will go up by the ratio of the voltages squared. So, as someone said earlier, yes you will get more heat, but for how long before burning out the elements is anyone's guess. The manufacturer can probably answer your questions without guessing. ;)
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Tom
 
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This was used were three phase Y only using 2 of 3 wires
Safe is to use a buck and boost transformer some time it can be wire for 240v but not label

Dave

I recently acquired a muffle furnace in an auction. The nameplate specifies 208 volt single phase input. Am I going to fry it if I use standard 240 volt input? If so, is there an economical way to convert 240v to 208v?

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Thanks for the replies. After a brief examination, it looks like 2 of the 4 heating elements are probably shot (no continuity). I may just the replace them with elements made for the higher voltage. More disassembly and research are in order...:cool:
 
Running it on 220-240 will not hurt it, short term. But long term, you will be looking for the heating elements to fail faster. A buck-boost arrangement to pull 240 down to 208 is the simplest solution. Since a buck situation is involved, the KVA rating will only involve the difference of each leg. Thereby saving you a few bux. But, there must be an old timey electrician doing the hook-up. The transformer will have eight leads. Find someone that knows transformers. A "bulb snatcher" won't cut it.

Some folks will comment you need a variac or some such. While a variac will work, and work well, the cost of one big enough to meet your needs will drive you to setting up bank jobs instead of machining.
 
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