High Voltage Check

[Sam Goldwasser]

There is a relatively safe way to calculate the secondary voltage - no
mains energisation required; it's just not too accurate as it takes no
account of losses.

Which are extremely high in a microwave oven transformer.

Got a DMM with a decent inductance range? You can get a ballpark
value thus:

Yeah, how many have that?

Zp=sqrt( (Rp^2) + (2 * PI * f * Lp)^2 );
Zs=sqrt( (Rs^2) + (2 * PI * f * Ls)^2 );
np/ns=sqrt(Zp/Zs);
Vp/Vs=np/ns;

Where f is your local line frequency.

That sounds like the hard way.

Just run it with 1/10th the input voltage as has already been suggested.

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[John G]

TYPO
Since you need to ask, you do NOT know enough to undertake this type
of repair as it could very quickly lead to your family having to call
the
Undertaker.

 

[Allodoxaphobia]

Very, very, very, very, very, very, very, very, very, very, very, very
carefully.

Don't even THINK of touching any part of the multimeter while testing.

Brings back memories of testing the H.V. used on the magnetron in the radar
system of the USAF F-102 on the mock-up bench at Ramstein AB
back in the early to mid-60's. I would clip several USM-6's in series
and spread them apart on a large piece of plywood. Then I'd clip them
onto the H.V. points in the T/R unit and power up the thing. I'd
stand back about 2-3 feet and read each meter -- then add the values
together. It was probably just plain dumb luck that I recieved
an _honorable_ discharge instead of receiving some sort of _other_ discharge.

Jonesy

 

[ri]

Thanks everyone who answered to this subject :
Problem is solved and one on the transformers is perfect for my purpose . Thanks
again to all .

 

[James Sweet]

Hi Group , all I am working with here is the High Voltage Transformer
itself . The rest of the microwave oven has been discarded as trash . I
need a transformer that has an output of 1,500 volts for use as a plate
transformer . I have several microwave transformers to test .
This brings me back to the question of testing the voltage . How is the
best way to check the voltage ? Thanks again .

Several have already answered your question... feed the transformer a lower
AC voltage and measure the correspondingly lower output.

 

[James Sweet]

30 mA will ruin your day hand to hand.

I got bit by a NST once, it did NOT feel good, however my finger wasn't
reduced to ash as it could have been by a microwave transformer. Both are
dangerous but the as others have said, the current from a NST is much lower.

 

[ri]

Yeah James , thanks . That is what I did and 1 of the microwave transformers
will be perfect for my plate voltage supply . Thanks James and all who gave a
good answer to my question . Thanks again

 

[NSM]

Hey kip , screw off . I work with electricity almost everyday . I know what
it can do. Screw off

That'll get you a lot of help. You come off like someone who knows nothing.
Expect to be treated as such. almost everyday. And you don't know what
electricity can do until you lose your hearing and you are sick to your
stomach for 15 minutes. There are old electricians and there are bold
electricians but there there are no old, bold electricians

N