Ted Samuels wrote:
DoN. Nichols wrote:
According to Ted Samuels :

[ ... ]

Got quite a surprise today. Tried running one of my 60 volt DC motors (I
thought they were 90 volt motors) with a variac and my setup tripped the
breaker in my power bar. Checked and rechecked the circuits from the variac
through the bridge and motor and everything seemed logical. tried it again and
again it tripped (not very smart really). Then I happened to notice in small
print on the very front of the variac "360 cycles per minute" 6 HZ

Oh yes. Google 6 HZ and you'll get more hits then you would ever imagine.
Believe me I had to do a double take when I read the "per minute".

I think the deal is that that there just are not enough turns to produce enough
CEMF, so at 60 hz and 110 volts the windings that are there, did not short
circuit, but really there was just to much amperage for the breaker.

T talking as if he knew something about the subject.



I've never seen one of those, and I would think that one for such a low
frequency would have enough iron so it would have no troubles with 60 Hz. Are
you sure that wasn't "360 cycles per second"? That would be close to the 400 Hz
ones which I have used -- and *those* just plain won't work with 60 Hz at
normal voltage. :-)

also -- was it a genuine Variac (made by General Radio), or another brand of
variable autotransformer? The 400 Hz ones above were genuine Variacs.

I have no doubt. The variac is a genuine Variac.

Enjoy, DoN.

Got to correct a couple of statements I made:

1st. While this unit carries the registered "Variac (R)" name, it was made by Technipower
of Davis instruments and calibration

2nd. I initially read 350 cycles per minute but when I was on the computer I
automatically assumed that I must have read 360 CPM , (Makes more sense to me.)
On a re read I find that it actually says "350 Cycles Min."

God I hate making mistakes.

T