Boat Neutral Bond

[rozza_b]

Hey all,

Have recently re-wired my boat after finding the previous owner had done a disgraceful job of it, replaced the stainless bolt that was through my console as the neutral point with a actual neutral bar but now im left wondering though do i need to bond the hull of my boat to the neutral ?? have done a heap of reading online but to be honest never seem to be able to get a definitive answer some say yes some say no......if yes what do people use to connect the neutral to the hull to prevent galavanic reaction (ie not a stanless bolt lol) I am a sparky by trade but this is somewhat outside of my normal scope of work, anyways thanks in advance

Rozza

[Fab1]

In a aluminium boat all earths should run back to the battery via the use of insulated busbars etc.Your engine should be earthed directly to the battery.All accesorry grounds should go to a busbar that should run to the battery.Never wire a ally boat like a car where the body is a ground(in this case theHull),that's the worst thing you can do.

Hope this helps mate.

Edited January 5, 2016 by Fab1

[Ric001]

Hi fab1. I agree with all dc sources being run back through low resistance cable to the battery. What are your thoughts on chassis bond as the secondary path similar to aircraft which are also aluminium. They do it primarily for static issues to remove electrical noise. I am not suggesting the boat frame be the only dc return path to the battery.

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[Fab1]

Hi fab1. I agree with all dc sources being run back through low resistance cable to the battery. What are your thoughts on chassis bond as the secondary path similar to aircraft which are also aluminium. They do it primarily for static issues to remove electrical noise. I am not suggesting the boat frame be the only dc return path to the battery.

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For aircraft it is all good and well earthing wherever they see fit. I can't think of any valid reason why you would want to run your grounds on a ally boat through the hull.The KISS principle has always worked for me,besides most planes I've seen don't operate in a saltwater environment hence the reason for not earthing through the hull.

Others may disagree.

[Ric001]

True about most planes and salt water but believe me Coke tea Coffe vomit and toilet water as well as humidity is a huge issue for airframes. As I mentioned we always had a primary return path being wire but also a secondary path being the frame. When talking with the fitters we joked about it being like the case drain in a hydraulic system to catch the drips that the primary return missed. [emoji106]

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[rozza_b]

Thanks for the input so far,

Yeah already using a insulated neutral bar that bonds everything back to my battery neutral through a cable and my engine is wired directly back to my battery, would never use the hull as my neutral even in a car i don't really like the idea of it either would probably still run a neutral cable, i guess my thoughts are along the same lines as Ric001's hence why i asked the question, i wonder if bonding the neutral would actually cause the boat to react more with salt water ? i imagine plane frames would face many of the same problems as boat when they are flying large distances over oceans (although its not the same as being in the ocean the air still holds some salt)