Quoting Ed Harris:

 EH> I have seen that Richard Hull and the TCBOR use something    
 EH> they refer to as  only: potential transformers . They seem   
 EH> to be rather more compact than pole transformers and can     
 EH> handle maybe 3KVA or so at 15000 volts... 

 EH> Anybody know what these are normally used for and where one  
 EH> might be able to obtain one and how much. 

Potential transformers are standard fare in power substations.
These are potted transformers with a core configuration very
similar as those used for step-up xfmrs in X-Ray machines.

These transformers are constructed to exacting specifications and
are used to connect sensor equipment to HV lines in order to
monitor voltages. The primary/secondary turns ratios are precise.

I have also seen these transformers in substations stepping down
a kilowatt or two to run cooling fans on the heavy 3 phase step-
down transformers.

Richard Quick

... If all else fails... Throw another megavolt across it!
___ Blue Wave/QWK v2.12