MOT Measurements

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Original poster: "Matthew Smith by way of Terry Fritz <twftesla-at-qwest-dot-net>" <matt-at-kbc-dot-net.au>

Hi All

I was hoping to be able to report success with a potential divider that
I have just built for my DMM, which allows me to measure transformer
output up to 7kV (Vout=Vin/10), but...

Despite having even labelled the wretched thing, I managed to connect
the DMM probes across the wrong terminals.  There are now several tracks
missing from the PCB inside my DMM - completely fried; it's going to be
a long job with silver loaded paint to repair that!

Nevertheless, if anyone wants instructions for a cheap ($15 Australian),
simple and safe (although not idiot-proof) voltage divider, let me know
and I'll post construction details and design notes on my site.

Now, a question...  It looks like the MOT that I was testing is putting
out about 6kV unloaded; is this normal?  Second question: what would
make a good test load for the secondary to get a truer idea of the
output voltage?  I know the technique of reversing the transformer (feed
secondary, measure primary) but I want to do things this way round as an
academic exercise.  Any pointers would be appreciated.

Cheers

Matthew Smith