PT Questions

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Original poster: "S & J Young by way of Terry Fritz <twftesla-at-qwest-dot-net>" <youngs-at-konnections-dot-net>

Hi,

I have questions about HV Potential/Instrument Transformers of the type some
use to power their TCs:

1) Why are they so "beefy" so that they are at least 1 KVA?  Are they used
to power a few lights or other things as well as a voltmeter that only
requires miniscule power?

2) Are most PT primaries "two-horn" style with neither primary side
grounded?

3) Are typical PTs dry, oil immersed, or potted?

3) Does anyone in the US have one for sale at a reasonable price?  I am
interested in a two-horn ungrounded configuration, 14 KV at around 2-3 KVA
intermittent duty,  120 or 240 volt 60 Hz secondary, preferably dry style.
I prefer an ungrounded HV winding so it can drive a bridge rectifier with
one side grounded.

4) What commercial source has the best deals for them?  T&R?  Austin?

5) Do utility companies take them out of service?  Seems like they would
last forever and not need replacement.

Thanks,
--Steve