Can anyone differentiate the philosophy behind tripping on 59N vs. alarming on a 59N?
Factors for consideration include:
This is in a Combustion Turbine Generating Unit.
VT on the LV side of the Generator Step Up Tx (after the Generator circuit breaker) is providing the open delta potential.
59N Element will be included in the GSU Transformer protective relay (generator protection is being covered by other relays).
There is a tap from the isolated phase bus between GCB and GSU to a Unit Auxiliary transformer (UAT protection similar to GSU).
It appears to be a standard to alarm only on 59N given this configuration. If so, why exactly? Thanks.
Factors for consideration include:
This is in a Combustion Turbine Generating Unit.
VT on the LV side of the Generator Step Up Tx (after the Generator circuit breaker) is providing the open delta potential.
59N Element will be included in the GSU Transformer protective relay (generator protection is being covered by other relays).
There is a tap from the isolated phase bus between GCB and GSU to a Unit Auxiliary transformer (UAT protection similar to GSU).
It appears to be a standard to alarm only on 59N given this configuration. If so, why exactly? Thanks.