Hi Jim,
I must disagree with your post. The advice is often given to determine an
NST's secondary voltage by feeding 120VAC to the secondary and measuring
the resulting Vprimary, this makes sense. However, having tried this, it
doesn't work. There's some very non-linear stuff going on with NST's, even
well below saturation. There was a thread on this topic several years ago,
I don't recall the resolution.
Regards, Gary Lau
MA, USA
On Thu, Jun 7, 2012 at 10:38 AM, Jim Lux<jimlux@xxxxxxxxxxxxx> wrote:
On 6/7/12 6:29 AM, mrapol@xxxxxxxxxxxx wrote:
I know the usual formula Vs/Vp = Ns/Np for calculating transformer
voltages, but I have a problem in that I am dealing with a sealed NST
and don't know the number of secondary or primary turns. What I am
trying to do is calculate the output of a 12kV NST when it's getting
less than 110 volts input. For example, if I feed the NST 30 volts AC,
what does it put out? Is there any way to figure this out without a high
voltage meter (which I don't have) and without knowing the number of
primary or secondary turns?
with no load, and with the voltage LESS than the nameplate input voltage,
it scales linearly (the turns ratio isn't changing, after all)
12kV out for 120V in
3kV out for 30V in
You can also put 120V *in* on the secondary, and measure the primary
voltage.. 120V in gives you 1.2V out..
For larger than nameplate voltages this won't necessarily work: core
saturation and breakdown...