Is it normal for the metering and protection functions to differ for the same current transformer?
Thread Content
Is it normal for the motor outlet to share the same current transformer, with different secondary side metering and protection ratios?
The current transformer ratios for the same motor are identical; the only differences lie in the accuracy levels required for metering and protection, as well as in their saturation curves. The metering requires a higher level of accuracy, while protection requires a lower level of accuracy.
It’s common for the accuracy grades to differ; it’s the first time I’ve seen two sets with inconsistent secondary turns ratios