EddyWirbelstrom
Electrical
- Feb 17, 2002
- 214
An existing Westinghouse IQ-1000 II motor protection relay does not have a Core-Balance CT, however its Ground Fault trip element is enabled and set.
The manual states that ground fault detection requires an ''optional ground fault (zero sequence) transformer be installed''.
If only 3 phase CTs are installed, does the relay determine the ground fault current from the residual current of the three phase CTs ? Or will the relay ignore the ground fault setting because there is no core-balance CT connected ?
The manual states that ground fault detection requires an ''optional ground fault (zero sequence) transformer be installed''.
If only 3 phase CTs are installed, does the relay determine the ground fault current from the residual current of the three phase CTs ? Or will the relay ignore the ground fault setting because there is no core-balance CT connected ?