Please check your shore power leads this w/e

sailorman

Well-Known Member
Joined
21 May 2003
Messages
78,991
Location
temp ashore, i expect to be back🤞
Visit site
A impulse buy in Aldi Wednesday, i saw a plug-in mains testers @ £2 so had one.
checked the boat supply this morning, NO EARTH :(.
Found this in the dog lead adapter for the boat plug / socket
IMG_1159_zps89938628.jpg

the earth wire some how had been blown / corroded ( obvious water ingress) away, not even any sign of the earth sheathing.
how long its been that way is anybody's guess & we are very fortunate that nothing went "LIVE".
Please please check your system
 
I'll second that

Electrics1.jpg


I now make a point of pulling apart my shorepower sockets annually to check their condition
 
As an added warning to the above, I would strongly advise anyone purchasing new ready made mains cables to open them up and check terminals. In the last 12 months I have found two (out of the box, as it were) to have seriously loose connections.
 
Last edited:
You also need to do a proper re-wire.
A couple of years ago one of the cross channel ferries suffered a serious fire due to poor re-wiring of an extension cable like the above.
These cables are used to plug in refrigeration units/trailers on cross-channel trips.
If I remember correctly the mistake was nothing more than the guy stripping the shielding where the wire went into the pin instead of letting the pin connector cut the shielding itself. The sort of pin connector where a blade cuts through the sheave and touches the core.

A couple of years ago I had just left Washington Marina when about a third of the marina/boats were wiped out due to poor cable connections.
 
I have a tester plug permanently plugged in - cheapo thing from Maplin that gives 3 lights if all fine, but a different combination for missing earth,neutral-live reverse and so on.

So it's the first check whenever I plug into a marina supply. Not surprisingly European marinas often have neutral live reversal as their internal plugs can go in either way and they (sensibly) have DPDT switch in their plug sockets. So I have a short well marked lead that reverses live and neutral as all my internal AC sockets are UK type.
 
I made the mistake of dismantling the Osculati shore power connector on our boat a few weeks ago - only to find that it is effectively a "fit once" device - the cable clamp locks on and if you do manage to pull the cable out (I did), it's pretty much impossible to re-insert it!
 
the earth wire some how had been blown / corroded ( obvious water ingress) away, not even any sign of the earth sheathing.
how long its been that way is anybody's guess & we are very fortunate that nothing went "LIVE".
Please please check your system

Looks like its been cut to me. Who you upset ?

I take it this is a lead you inherited with the boat ?

Maybe cut off by previous owner who is one of those misguided souls who beleives that a boat is safest if there is no earth connection on board.
 
Maybe cut off by previous owner who is one of those misguided souls who beleives that a boat is safest if there is no earth connection on board.

+1 - definitely doesn't look "corroded away" to me. Looks like it was never installed.

I built my own shore-power leads (cheaper to buy the connectors and a drum of cable than ready-made) so I know they're wired up right.

Pete
 
Looks like its been cut to me. Who you upset ?

I take it this is a lead you inherited with the boat ?

Maybe cut off by previous owner who is one of those misguided souls who beleives that a boat is safest if there is no earth connection on board.

I must have wired it up :), there are strands still in the end of the earth pin so it was connected at one time.
 
I have a tester plug permanently plugged in - cheapo thing from Maplin that gives 3 lights if all fine, but a different combination for missing earth,neutral-live reverse and so on.

So it's the first check whenever I plug into a marina supply. Not surprisingly European marinas often have neutral live reversal as their internal plugs can go in either way and they (sensibly) have DPDT switch in their plug sockets. So I have a short well marked lead that reverses live and neutral as all my internal AC sockets are UK type.


just ordered one for our boat, thanks for the idea
 
Looks like its been cut to me. Who you upset ?

I take it this is a lead you inherited with the boat ?

Maybe cut off by previous owner who is one of those misguided souls who believes that a boat is safest if there is no earth connection on board.

Could also have been cut but the previous owner to stop the earth leakage from tripping,

2 neons wired permanently. line to earth neutral to earth would have shown the fault straight away. As I have
 
That's why I always use clear plugs and sockets:

42251343.jpg
CN0670306-40.jpg


Also has the advantage that you can put a neon inside the socket to check you have power.

Plug: http://cpc.farnell.com/walther/210306cl/3p-240v-bs4343-clear-plug-blue/dp/CN06701
Socket: http://cpc.farnell.com/walther/31036cl/3p-240v-bs4343-clear-coupler-blue/dp/CN06703

They also sell testers: http://cpc.farnell.com/pro-elec/t203/mains-tester-plug/dp/PL10052

[Later] And a tip, don't do what I did (aged 17) when checking the wiring on an extension lead: unplug it first!
 
Last edited:
Also has the advantage that you can put a neon inside the socket to check you have power.

Now that's a clever idea. Would have saved me a certain amount of hassle at St Vaast, where you have to press a button to enable the socket, but to confuse matters the power-pole nearest us wasn't actually working.

I think the new electrics panel is going to include one of those three-neon testers permanently wired in. At the moment the only way of detecting a successful mains power hookup is the fridge going to uber-freeze mode :)

Pete
 
When you wire a LNE cable/plug it is a good idea to have the wire lengths cut such that the first to pull out/break is the L and the last the earth, if someone pulls the cable and the cable clamp fails to hold. That way you notice something is wrong (no power) while you still have an earth connected. On normal UK square-pin sockets you get the opposite (most dangerous) effect if you make all the wire tails the same length.
 
Last edited:
Apart from MF stuff all your low voltage AC stuff should have a service regime just like the rest of the stuff on a boat anyway, usually a simple visual inspection is enough to avoid stuff like this happening. Also if you cable up your own shore lead (or anything else where there is direct screw pressure to the conductors like plugs etc.) make sure you put bootlace ferrules on the conductors to avoid fraying reducing the cross section or in extremis actual parting, in fact even if you buy one check it has bootlaces and if not pop some on, the type with bell mouths to avoid a hard edge are best but the type with a small insulated collar are best of all, they are so cheap there is no reason not to use them. This goes for ultra (extra) low voltage DC too, in fact the standards now require it.
 
I think the new electrics panel is going to include one of those three-neon testers permanently wired in.

I wouldn't, you will be introducing a connection between live and earth, albeit via a high resistance. Just use a single mains neon indicator for the live, and make a point of testing when you plug in. In Greece I used to carry a 16A crossover lead, about 10% of the power outlets were L / N reversed.

+1 for bootlace ferrules, but you need the right crimp tool to fit them.
 
Last edited:
That's why I always use clear plugs and sockets:

42251343.jpg
CN0670306-40.jpg


Also has the advantage that you can put a neon inside the socket to check you have power.

Plug: http://cpc.farnell.com/walther/210306cl/3p-240v-bs4343-clear-plug-blue/dp/CN06701
Socket: http://cpc.farnell.com/walther/31036cl/3p-240v-bs4343-clear-coupler-blue/dp/CN06703

They also sell testers: http://cpc.farnell.com/pro-elec/t203/mains-tester-plug/dp/PL10052

[Later] And a tip, don't do what I did (aged 17) when checking the wiring on an extension lead: unplug it first!

Brilliant idea especially with the neon. Another line on the to do list.......
 
Top