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Thank you all. Indeed I am considering the relay response time as outlined by the protection curve time plus 3 cycles (42 ms) as the provided manufacturer's maximum interrupting time for the downstream device. The resulting curve should reflect the overall clearing.

Agreed. What I meant was "maximum permitted burden to maintain 20x rated current with less than 10% error". Obviously you can have a higher burden and lose accuracy.

Thanks, Protoslash. 100ms (6 cycles) sounds more reasonable for electronic reclosers.

DM61850, I am not really sure why your answer would contradict mine as I totally agree with you. What I basically said is that his CT does not saturate because he'a got a small burden for his CT (1 Ohm) even though the secondary current is higher than 20x the rated current.

Thanks for answer cranky. So when I said cooper I basically referred to the Electric Power Distribution Handbook, where 12 cycles are recommended. What I have seen in some literature is that a specific CTI range (or guideline) is recommended for hydraulic reclosers in spite of the manufacturer...

A C200 (B2.0) CT will allow you to keep accuracy when the burden is up to 2 Ohms (200/(5*20) = 2 Ohm). The reason you still have a knee voltage below 200V is that your burden is only half of the maximum permitted. If the burden you calculated is correct, there is no reason to go for a 1000:5 CT...

Hi there. I am trying to coordinate two electronically-controlled reclosers (e.g. ABB PCD2000). My question is what would be the minimum Coordination Time Interval for two electronically controlled reclosers considering that the downstream recloser curve already contains the manufacturer's...