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-   -   Is this bilge pump wiring as bad as I think? (http://www.sailnet.com/forums/electrical-systems/92920-bilge-pump-wiring-bad-i-think.html)

GrahamO 10-10-2012 10:00 AM

Is this bilge pump wiring as bad as I think?
 
Getting to know my boat; I noticed that the 12V side wiring for my bilge pump actually has an open terminal strip connection in the bilge, all be it just below the floorboards.

It strikes me that having the bilge pump keep going as long as possible would be a good idea so I am thinking of making sure there are watertight connections at least until the top of the engine compartment.
does this make sense or am I missing the point somewhere?

I'm also planning on installing a second bilge pump and perhaps a bilge alarm although the case for the alarm is unconvincing because if we are there we will hear the pumps (or get wet feet) but the real risk is when we are not there.

Thanks

chucklesR 10-10-2012 10:10 AM

Re: Is this bilge pump wiring as bad as I think?
 
You can't go wrong with water tight electrical connections on a boat.

The second pump is a good idea. There are several articles here that relate how to do a dual bilge pump system. Basically the smaller pump goes deeper and gets the most use getting out the everyday stuff, then the larger one kicks in.

Put a counter in the circuit- as you said the alarm is only good while you are aboard - the counter lets you know what's going on all the time.

FarCry 10-11-2012 10:52 PM

Re: Is this bilge pump wiring as bad as I think?
 
I put an open terminal strip on my bilge for a couple of reasons. With a tester I can quickly see if there is power to the float switch, power to the bilge pump, without cutting into a crimped connection. It is easier to replace the pump or switch when they fail. There are clear advantages to making all connections as watertight as possible. In my case I found more advantages in keeping things open yet sprayed with corrosion reducing spray.

L124C 10-13-2012 02:48 PM

Re: Is this bilge pump wiring as bad as I think?
 
You didn't mention if the strip is on the Pos or Neg side of the circuit (a pictures worth a thousand words BTW). Sounds like in an emergency situation it could be submerged, (potentially leading to a bigger emergency where the entire boat is submerged!). If it is positive, would this short it out (I don't know, had never thought about it)?
In any case, IMO, cutting crimping/soldering and waterproofing wires is easy enough. I want all wiring related to my bilge sealed. Bilge pumps and switches can be problematic enough, even when properly wired. No sense complicating the issue!
Regarding a second pump: I installed a diaphragm pump as a bilge maintenance pump. Worked out well. Search for my thread here if interested.

erps 10-13-2012 03:07 PM

Re: Is this bilge pump wiring as bad as I think?
 
I'm currently with FarCry on this. I use heat shrink connectors pretty much everywhere on the boat along with terminal connectors. I hate butt connectors. Almost every failure I've had in old bilge wiring has been at butt connectors.

Will an open terminal connector short out if it goes underwater? I don't know, but I think it's easier for the electricity to pass through the pump and make it work than it is to jump a gap through sea water to bypass the pump.

L124C 10-14-2012 01:31 PM

Re: Is this bilge pump wiring as bad as I think?
 
Quote:

Originally Posted by erps (Post 933127)
Will an open terminal connector short out if it goes underwater? I don't know, but I think it's easier for the electricity to pass through the pump and make it work than it is to jump a gap through sea water to bypass the pump.

Yeah...thats what I was thinking. Probably the larger issue with the exposed strip in the bilge is corrosion, which could lead to pump failure. I couldn't be bothered spraying it with anti corrosive material on a regular basis.

GrahamO 10-14-2012 02:15 PM

Re: Is this bilge pump wiring as bad as I think?
 
Having spent most of my career trying to make electrical devices work under water I can answer that one. First Salt water is a great conductor (only about 0.2ohms per meter) and will definitely be preferred to the high impedance pump - IF there is a circuit. In this event boats are interesting.

There are three 'voltage rails' on a boat:
1: +12v
2: 0v
3: 'Earth' - normally the bonded through-hulls coupling to the ocean (a great earth).

As far as I have seen the battery 0v rail is not connected to 'Earth' on boats. Therefore, to short out the open +12v connector a 0v connector has to be in contact with the sea water. Trouble is people generally do less to protect the 0v rail than the +12v rail so there is a good chance that if the water has reached the bottom of the floorboards it will also have found a 0v path. If this is the case the bilge pump breaker will immediately trip.

Given that I would like the bilge pump to keep working as long as it can (even if thoroughly beaten.... I plan to ensure waterproof connectivity at least to the top of the engine compartment. I was just wondering why this is not normal practice (at least on my boat).

mitiempo 10-14-2012 02:20 PM

Re: Is this bilge pump wiring as bad as I think?
 
I always wire a bilge pump to be waterproof as high as possible. On my own boat it is waterproof right to the panel and the only wire in the bilge as well. A good crimped butt connector with adhesive heat shrink is totally waterproof.

GrahamO 10-14-2012 03:54 PM

Re: Is this bilge pump wiring as bad as I think?
 
Quote:

Originally Posted by mitiempo (Post 933491)
I always wire a bilge pump to be waterproof as high as possible. On my own boat it is waterproof right to the panel and the only wire in the bilge as well. A good crimped butt connector with adhesive heat shrink is totally waterproof.

Not sure I would completely trust adhesive heat shrink. I would cover it in self amalgamating tape or self-fusing tape as it is also called. That stuff really is bomb proof used correctly. One of the problems we have found with heat shrink is that it can trap moisture and result in hidden corrosion. Adhesive is better but still not perfect.

eherlihy 10-14-2012 05:15 PM

Re: Is this bilge pump wiring as bad as I think?
 
Quote:

Originally Posted by FarCry (Post 932411)
I put an open terminal strip on my bilge for a couple of reasons. With a tester I can quickly see if there is power to the float switch, power to the bilge pump, without cutting into a crimped connection. It is easier to replace the pump or switch when they fail. There are clear advantages to making all connections as watertight as possible. In my case I found more advantages in keeping things open yet sprayed with corrosion reducing spray.

This is why I used an Ultimate Bilge Switch from Ultra Safety Systems;
  • They are supplied with adhesive lined heat shrink connections. If you don't use these, the warranty is void.
  • There is a green LED on the top of the switch. If there is 12V provided to the switch, the LED is on. No multimeter is necessary to verify that power is supplied to the switch.

http://www.tefgel.com/images/pusw001_1.jpg


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