Dear Forum memebers,
I am having a discussion with a design engineer regarding the installation of two 3.0 MVA 400 V diesel sets. The sets will be used to feed the grid at 33 k V. The consultant is proposing fuses on the HV side of each 400 V/33 k V generator/transformer and a common 33 kV switchgear at the delivery point where metering will be done. It is also worth mentioning that the two sets are located at two different sites 500 m apart. The fuses will be pole-mounted. I understand that a 33 k V switchgear is by far very much more expensive than a set of fuses but a switchgear will offer much better protection on the HV side of the transformer . A fault inside a transformer will leave it unisolated unless the main switchgear is made to trip by interconnection. Basically what is required as protection features for a transformer of this size, 3 MVA. Is overcurrent alone enough ?
Thanks for your input.
Guardiano
I am having a discussion with a design engineer regarding the installation of two 3.0 MVA 400 V diesel sets. The sets will be used to feed the grid at 33 k V. The consultant is proposing fuses on the HV side of each 400 V/33 k V generator/transformer and a common 33 kV switchgear at the delivery point where metering will be done. It is also worth mentioning that the two sets are located at two different sites 500 m apart. The fuses will be pole-mounted. I understand that a 33 k V switchgear is by far very much more expensive than a set of fuses but a switchgear will offer much better protection on the HV side of the transformer . A fault inside a transformer will leave it unisolated unless the main switchgear is made to trip by interconnection. Basically what is required as protection features for a transformer of this size, 3 MVA. Is overcurrent alone enough ?
Thanks for your input.
Guardiano
