Barge electrics
Barge electrics
(OP)
We have taken delivery of a 400ton steel-hulled dutch barge which has no less than 3 separate 3-phase 400/230v generators of around 40KVA. The control system is such that the generators cannot operate in parallel.
Setting aside the 24v dc installation, the electrical installation is as you might find it in any building with a number of 3-phase dist boards feeding lights sockets, compressors, pumps etc.
Noteworthy is that none of the gen-sets have had their neutral points connected to the steel hull of the vessel. I am not sure if this is deliberate since the frame of each set is connected to the neutral but the gen sets are mounted on rubber feed to reduce vibration.
I cannot think of any reason why we should not connect the star point of the sets to the hull.
I would appreciate any comments.
Setting aside the 24v dc installation, the electrical installation is as you might find it in any building with a number of 3-phase dist boards feeding lights sockets, compressors, pumps etc.
Noteworthy is that none of the gen-sets have had their neutral points connected to the steel hull of the vessel. I am not sure if this is deliberate since the frame of each set is connected to the neutral but the gen sets are mounted on rubber feed to reduce vibration.
I cannot think of any reason why we should not connect the star point of the sets to the hull.
I would appreciate any comments.
Regards,
Lyledunn






RE: Barge electrics
Bill
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"Why not the best?"
Jimmy Carter
RE: Barge electrics
Not that I believe the generator should be effectivly grounded, but a high impedance ground would allow a ground fault detection. And a grounded frame would be safer for those who work on them.
Shore power would require an isolation transformer, and a set of three transfer switches.
With the generators electrically seprated, the combined fault current would never come into play.
RE: Barge electrics
RE: Barge electrics
The main reasons for running ungrounded are for safety and to avoid corrosion when on shore power. Search this site. Corrosion issues from shore power connection have been discussed several times.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Barge electrics
I would disconnect that star point and make sure I have ground detection installed.
RE: Barge electrics
There will be no shore power, even though the facility exists. Given that consideration and the fact that the neutral is distributed, can you conceive of any reason why I should not connect the hull to Gen set neutral?
Many thanks for the replies. They have been very useful.
Regards,
Lyledunn
RE: Barge electrics
Similarly, a less than full bolted earth fault can result in a arcing fault that may not trip the protective device. If ungrounded neutral there will only be an indication on the ground detector and no resulting damage.