kassar
Electrical
- Oct 13, 2006
- 1
Greetings everyone. I am new here but Hope this will be the beginning of fruitful discussions with all of you.
We have a 2 MVA, 11/2.2 KV, 50 Hz transformer feeding compressors. The overcurrent and earth fault protection for the transformer is provided through a type MCGG 52 relay and an indoor SF6 circuit breaker. The relay settings are as follows:
Current setting
Is = 1.2 In
t = 0.4x
Instantaneous
Iinst = 10 Is
Earth fault
Ie=0.3Is
t = 0.2x
CT ratio 250/1 A
Standard Inverse curve
Considering that the HV full load current of the transformer is 105 A, is the transformer adequately protected? What do these settings really mean?
Thank you for your anticipated help.
We have a 2 MVA, 11/2.2 KV, 50 Hz transformer feeding compressors. The overcurrent and earth fault protection for the transformer is provided through a type MCGG 52 relay and an indoor SF6 circuit breaker. The relay settings are as follows:
Current setting
Is = 1.2 In
t = 0.4x
Instantaneous
Iinst = 10 Is
Earth fault
Ie=0.3Is
t = 0.2x
CT ratio 250/1 A
Standard Inverse curve
Considering that the HV full load current of the transformer is 105 A, is the transformer adequately protected? What do these settings really mean?
Thank you for your anticipated help.