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Connecting battery negative to hull

A few months back I had someone look over the boat and I was told the battery 0V must be connected to the hull bonding point to pass the BSS. Is this correct?

Asked by: Adam Savory  | 12.48pm, Saturday 3 February


WW says:

Boat Safety Scheme check 3.7.2 does indeed look for the presence of a low resistance cable between the engine or starter motor and the battery negative (also known as the return or 0V connection).
Obviously for a starter motor to operate efficiently and safely, it needs good electrical connections and this is the purpose of the BSS check. If however your boat does not have an engine and the batteries are charged from solar panels; a connection between 0V and the hull whilst not required for the BSS does make for a safer system. This is because a floating 12/24V system (ie not bonded to earth) will accumulate static charge and can end up "electrically floating" at several hundred volts. It will still supply 12/24V but with an associated risk of electric shock.
It is important to only have a single earth connection to the hull, which is usually the engine, this ensures that currents do not flow through the hull which will cause galvanic corrosion.

Rupert Smedley  | 4.27PM, Saturday 3 February

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