Protection Engineering Basics and Schemes Protection Engineering | Page 42

We can kept Potential transformer secondary open ,
because on secondary the voltage will be low , but it does
not means it is save to work on open secondary of PTs .
Please make safe distance on work while working on PT
and always use Personal protective equipment. Especially
hand gloves with voltage rating of at least 600Volts.
Like current transformer it is also divided in two types by
means of application
 Metering PT
 Protection PT
1.2.2 Errors
Errors in any PT is
 Phase displacement error
 Ratio error
Phase Displacement error is
the phase difference between
the primary voltage vectors
and reverse secondary voltage
vector.
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