Underwater Electrics!!

[gtmoore]

Can anyone advise me of the best way to connect wires that potentially could end up underwater. I'm installing an electric bilge pump in a Moody with a very shallow bilge. and the pump has ended up in the deepest part of the bilge in the centre just aft of the keel reinforcement. The wires from both the bilge pump and the float switch are too short to run to the bunk locker where I can connect them up to the power etc in the dry so I am going to need to extend them. Are there the equivalent of waterproof crimp connectors? Powerstore seem to sell something along these lines but they just say they resist salt water - would this be good enough in this case?

Thanks

 

[hlb]

I'd just join the wires with whatever, then stick a big wad of sylicone round them.

No one can force me to come here-----------
----- I'm a Volunteer!!!

Haydn

 

[andyball]

you can buy crimp connectors with a heat shrink seal.....or just connect them as you normally would, and apply glue-filled heatshrink on top of the connections.....or real waterproof plug/socket connectors can be bought from maplins,rs,index marine etc. I'd extend the leads using the glue-filled h/s then fit whatever sort of connector you normally use. I find http://www.beal.org.uk/ v.cheap for glue filled hs.

 

[muchy_]

Apparently, 12v electrics will work OK underwater so just use ordinary connectors.

 

[yachtbits]

If you want to do a proper job,

make all your connections using crimp connectors,
then slide a length of adhesive lined heatshrink tubing over the whole lot,
shrink down just the bottom end of the heatshrink. Then fill the heatshrink with 3M - 2130 scotchcast. and leave to set.

This is good down to 1000mtrs water depth, I've proven it many times.

scotchcast is available from good electrical distributors such as Edmundsons or City Electrical Factors. It is often used by Electricity companies for cable joints upto 1500volts.

Note, don't leave joints ecpossed to water immersion, they will corrode!

kev



www.yachtbits.co.uk
sales@yachtbits.co.uk
marine electrical/electronics specialists

 

[Guest]

<<This is good down to 1000mtrs water depth, I've proven it many times.>>

Remind me not to come sailing on your boat then

Regards,

Peter
http://www.mistressofmourne.com

 

[andyball]

perhaps a layer of insulating tape too, just in case ?

 

[yachtbits]

insulation tape isn't waterproof, but Self-Almalgamating Tape is. This stuff is a stretchy rubber tape that bondes to itself. You have to build up a number of layers for it to work properly. Again purchase from electrical wholesalers.

1000mtrs, fortunatley, these vessels are not yachts and are remotely operated!!

kev

www.yachtbits.co.uk
sales@yachtbits.co.uk
marine electrical/electronics specialists

 

[gtmoore]

Thanks to everyone for the advice

Gavin

 

[bedouin]

The problem with that is that once salt water gets to the connectors it will start corroding the connectors and the wires and could fairly soon lead to problems

 

[andyball]

a plastic bag then ?,on top of the glue-lined heat shrink and the scotchcast......all in the shallow bilge : one can't be too careful.

 

[oldharry]

Solder the wires, rather than use a connector, then encase thoroughly in araldite for a totally impervious permanent connection.

Any water reaching elecytrical contacts will a) rapidly corrode them, and b) if ANY power is present result in rapid galvanic corrosion - only a fraction of a volt is needed.

Soldering ensures a solid path for the electric current, so that even if corrosion does occur, failure will be postponed until the wires actually part company!