this is a instrument, which measures kvah and also kva of maximum demand. it consists of a kwh meter and a reactive kvah meter in the common case with a special summator mounted between them. the summator is driven by both the meters through a complicated gearing, which makes the summator to register kvah at all power factors.
A group of machines (wind turbines) connected with 33KV
feeder and each machines are having individual VCB. The 33KV
feeder connected with 110KV/33KV substation. The 33KV feeder
tripped by over current at Substation and fault recorded at
Substation as OC-R&Y phase. Same time the group of machines
VCB tripped by over voltage, the fault recorded voltage was
above 66KV by numerical Under/Over voltage relay. While grid
drop time, this much of voltage hike is possible?