240v Boat Electrics safety

[MHS]

I am looking at buying a new boat which has been fitted out by a very good craftsman, and he has done all the work.

 

It has a Gas certificate and a BSS both issued last month, and will be supplied with a RCD certificate. Does the boat also have to be signed off by a qualified electrician with a Domestic Electrical Installation Certificate?

 

The work has been well done, and I phoned the BSS examiner, who told me that the installations are correct and safe.

 

Is this sufficient?

[leeco]

Boat electrics don't come under BS7671 or part P.

 

You just need to satisfy the BSS guy.

Edited June 11, 2014 by leeco

[BEngo]

No regulatory need for certificates but for real peace of mind check that:

 

There is a proper consumer unit with circuit protection devices.

There is an RCD. You could ask for this to be tested with an RCD tester, not just by pushing the button labelled 'Test' which doesn't really.

The Boat neutral is bonded to earth. Exact arrangements depend on whether and what sort of inverter is fitted

The boat earth is bonded to the hull. Ideally this will be close to the point at which the DC negative is bonded to the hull.

 

Other things to look for- a Galvanic Isolator or Isolation Transformer.

 

N

[Ark Right]

Hi MHS

The BSS has very little to do with boat electrical safety.

Is this the first boat your very good craftsman has fitted out?

Has he done all the electrical installation himself and therefore has a good knowledge of boat wiring and systems?

Is he conversant with the BMEA code for the wiring systems on boats, if not its doubtful the RCD certification he is supplying is of any value at all.

Is he a member of the British Marine Federation?

Is he writing his own RCD certification? Third party certification can be good if executed properly, though often it is not.

 

A

Edited June 11, 2014 by Ark Right

[MHS]

No regulatory need for certificates but for real peace of mind check that:

 

There is a proper consumer unit with circuit protection devices.

There is an RCD. You could ask for this to be tested with an RCD tester, not just by pushing the button labelled 'Test' which doesn't really.

The Boat neutral is bonded to earth. Exact arrangements depend on whether and what sort of inverter is fitted

The boat earth is bonded to the hull. Ideally this will be close to the point at which the DC negative is bonded to the hull.

 

Other things to look for- a Galvanic Isolator or Isolation Transformer.

 

N

Many thanks for the replies, there is an RCD fitted, and I am sure I saw the galvanic isolator between the consumer unit and the inverter. I will check these details tomorrow.

[trackman]

Isolation transformers and galvanic isolators are not electrical safety items though wrongly installed they might possibly make an unsafe boat.

They are alternative means to protect against galvanic corrosion of the underwater bits of a boat that might result from stray electrical currents. They are usually considered necessary if you use an electrical hook up from a shore mains supply.

Edited June 12, 2014 by trackman

[nicknorman]

Many thanks for the replies, there is an RCD fitted, and I am sure I saw the galvanic isolator between the consumer unit and the inverter. I will check these details tomorrow.

The galvanic isolator should only be fitted in the earth line from the shore power socket to the rest of the boat's earth system. Anywhere else is wrong.