CT Accuracy Class 2

[xabproject]

Hi,

Found on the nameplate of a CT (Gas Insulated Switchgear of Japanese make):

CT Ratio – 2500/1 A

Turns ratio – 1/2500

Accuracy class – 0.03X700R6

Can you please explain this accuracy class? I guess, CT class is X and 0.03A is mag current at knee point voltage 700V and winding resistance is less than or equl to 6 ohm.

Other CT has

CT Ratio – 3000/1 A

Turns ratio – 1/3000

Accuracy class – 0.02X250R5

Thanks.

 

[randyman]

I have seen something similar in format except your "X" was replaced by "PL". It was in New Zealand under Australian standard AS-1675.

The numbers represented max exciting current, minimum knee point voltage and maximum secondary winding resistance corrected to 75°C, in that order.

Does the nameplate state a standard?? I am familiar with the Japenese JIS series but do not recall ever seeing that format. Could be JEC-xxxx??

 

[scottf]

Your guess is correct.

<=0.03 A Iexc
>=700 Vkp
<= 6 ohms Rs