HOW TO CALCULATE CT AND VT RATIO IN PRTECTION AND METERING?

Answer Posted / naveen singh

To find out Multiflying factor
1) If meter CT Ratio is not given then CT Ratio provided in
the panel has to be considered. Example if CT Ratio in the
Metering Panel is 600/5 then the M.F is 120.

2) If CT Ratio is mentioned in the Meter then Meter CT
Ratio / CT Rating Provided in the Metering panel.
Example If the CT Ratio of the Meter is 600/5 and CT
Provided in the Panel 800 /5 then Multiplying Factor will
be 600/5 /800/5. i.e., 600/800 then M.F is 3/4 (0.75)

3)In addition to this any Multiflying factor is mentioned
in the Meter then it has to be multiplied. Example if Meter
CT Ratio is 600/5 and Panel Ratio is 800/5 and M.F
mentioned in the Meter is 3 then the M.F will be (600/800)
*3. i.e., 0.75*3 =2.25

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