Re: Why PT's?

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: ashumate3-at-aol-dot-com 

PT's are used on the higher voltage lines and also on many industrial 
metering applications. This is because most all meters are set up for 120 
volts and 5 amp applications. In addition to pt's you also have ct's 
(Current Transformers). The reason for this is to give some isolation from 
the line.

The PT's used for 14.4kv are on the small size. they get large for the 35 
and 165 kv applications.

120 volt output is for the meters which are spanned 0 to 120 volt. The 
scale shows the higher end of the voltage. Example - an analog meter scale 
will indicate 0 to 16kv at the top end. Again the same will apply to ct's. 
the top input of a ct may be 0 to 1000 amps. The output is 0 to 5 amps.

I hope this answers you question.

Al Shumate