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Hoffman Amps Forum image Author Topic: Old Variac - seems 400 - 1200 Hz - can be used ??? New Question  (Read 4497 times)

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Offline kagliostro

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Hi friends  :)

Iesterday in a little market I gor an old Variac

it was very bruised, not working and not clean

a 15 minute job, a little piece of abrasive paper, and now it is working

but cleaning it now I can read the nameplate and it seems is for 400  - 1200 Hz

May I use it (at 50Hz 220v) or is only a nice ornament ????

MANY THANKS for any suggestion

Kagliostro
« Last Edit: May 24, 2009, 05:22:09 pm by kagliostro »
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Offline FYL

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Re: Old Variac - seems 400 - 1200 Hz - may be used ???
« Reply #1 on: May 11, 2008, 06:37:12 pm »
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May I use it (at 50Hz 220v) or is only a nice ornament ????

I wouldn't use it.



Offline RicharD

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Re: Old Variac - seems 400 - 1200 Hz - may be used ???
« Reply #2 on: May 11, 2008, 08:12:36 pm »
Very odd.  I've seen ratings like that on meters but not a variac.  I'd set up a controlled experiment using incandescent lamps, a trusted volt meter and a trusted amp meter.  I'd bet it's OK, but my apprehension would be trusting something very old with supply voltage for amps on the bench.  The only thing worse than no test equipment is faulty test equipment.

Offline FYL

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Re: Old Variac - seems 400 - 1200 Hz - may be used ???
« Reply #3 on: May 12, 2008, 05:22:02 am »
Quote
Very odd.  I've seen ratings like that on meters but not a variac.

Quite common in avionics, where "mains" is at 400 Hz.



Offline RicharD

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Re: Old Variac - seems 400 - 1200 Hz - may be used ???
« Reply #4 on: May 12, 2008, 11:17:15 am »
Avionics..... well I change my reply to ornament then.  This explains the vintage meters I was pondering from Nebraska Sales.  I know nothing about avionics other than don't mess with the folks at the security check point.

Offline PRR

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Re: Old Variac - seems 400 - 1200 Hz - may be used ???
« Reply #5 on: May 17, 2008, 01:41:13 am »
Rated input at 50hz will be 14.3V. Will probably stand 15V or 16V for many minutes.

Unless you have a need for low-voltage variable AC, there is not much use in it.

Offline kagliostro

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Re: Old Variac - seems 400 - 1200 Hz - may be used ???
« Reply #6 on: May 17, 2008, 06:09:24 pm »
Hi  :)

MANY THANKS ( :'( :'( :'()

it will be better I use it as a nice ornament

Kagliostro
The world is a nice place if there is health and there are friends

Offline kagliostro

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Re: Old Variac - seems 400 - 1200 Hz - may be used ???
« Reply #7 on: May 24, 2009, 04:50:41 pm »
Hi

I resumed this old topic because I find this other topic

http://www.el34world.com/Forum/index.php?topic=811.0

can I thik to use my old 400Hz variac as in this PS ?

PRR told it can be use till near 14v

someone know how many current I can suck there ??

Thanks

Kagliostro

« Last Edit: May 24, 2009, 04:53:00 pm by kagliostro »
The world is a nice place if there is health and there are friends

 


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