Grounding on Ships
Grounding on Ships
(OP)
I have a project to build a control panel for a ship. The incoming supply is 440 V: 3 phase: 3 wire: 60Hz. I need a 220 volt supply for the control circuit and some little single phase motors and other small single phase loads. I shall fit a double wound transformer to obtain the 220 volt supply. Do I ground one leg of the secondary winding of the transformer to the metal work of the control panel enclosure, and hence the hull of the ship, or leave it floating? In other words, is the sea a good enough ground? If the secondary leg is left floating, it will have to be protected with a fuse or MCB presumably?






RE: Grounding on Ships
Then you will have 220V ( 1 ph supply) between L-N for your small power distribution.
You must also ensure that all single phase supplies feeders have 2 core cable connection ie L-N.
You must not use the ships hull as the N return path.
loads such as motors/control panels may be earthed (bonded) locally to ships hull.
RE: Grounding on Ships
IEEE Std 45
Military Standards and Specifications
etc.
RE: Grounding on Ships
jbartos thanks for tip on IEE STD45.
RE: Grounding on Ships
See Earthing in Ships - Thread238-51057...
RE: Grounding on Ships
“There’s none so blind as those who will not look!”