Installing New Bilge Pump and Auto Switch

[Bjohnson]

While sitting here in lockdown, my list of winter jobs for my boat gets longer by the day!

One of my key tasks is to install an Auto/Manual/Off switch for the bilge pump, install new wiring from console to the transom well and fit a new (auto) bilge pump.

Just after a couple pointers and informed wisdom;

- Obviously need to bypass main isolation switch. Is the preferred approach to origin of bilge pump supply for a direct connection at the battery terminals, or connect at the live side of the main isolator?
- considering whether to make the connection for the bilge pump via a waterproof connector (in case need to replace later on) or dirrct connect with soldered joint. Obviously soldered joint should be more reliable, less prone to failure risk, so i've probably answeered my own question!
- Is an additional inline fuse recommended at the origin of the connection (at battery or main isolator) or is fuse integral to auto/manual/off switch sufficient? Under the latter configuration the cable has no fuse protection but as 12V this probably isnt an issue

thanks

[treerat]

hello

when i rd did mine I added a waterproof connector as the things do die and it made for an easy replacement.

As for where to take the power - will this be for leaving afloat when not in use? If so i'd be adding a 2nd battery, nothing worse then rocking up to find the rain has used all the juice. If its for when afloat and alongside the other electrics, I'd be adding to the existing switch / bilge power line.

[GuyC]

I put mine on the live side of the isolator but I guess that putting it direct on to the battery would be OK if it was a neater way of doing it.

I used a junction box as high as possible to connect the wiring but I have a main pump and a second auto pump that I connected up so a box might be overkill for two / three wires.

https://www.asap-supplies.com/produc...ay-ip67-715960

I'd put a fuse as close to the battery / isolator as possible. 12V is still enough to start a fire if it shorts out. You can then pull the fuse when you don't need the pump or fit a switch. The second battery has been discussed recently.

https://www.rib.net/forum/f37/second-battery-84973.html

[Salty Pete]

This is my opinion.

- Obviously need to bypass main isolation switch. No! An isolation switch is used on a boat because of the moisture around wiring that will drain the battery. Connecting before the isolation switch negates the reason for having one.

Obviously soldered joint should be more reliable. No! Soldered joints are not reliable and should never be used where vibration will occur. Basically they are only used in printed circuits. Solder has no flexibility and will crack. Difficult to find the fault and more difficult to repair.

A fuse is always required wiring can get red hot and start a fire without one.

What is the reason behind your enquiry? Are you going to leave your boat in the water unattended?

[beerbelly]

i wired my auto bilge to the isolated switch panel for manual use the third wire for auto use i put a fused crocodile clip on if for any reason i leave it afloat overnight i turn the isolator off and put the crocodile clip on the pos terminal of the battery simple and works fine when not using it the crocodile clip clips onto the plastic battery tray

[GuyC]

Originally Posted by beerbelly

i wired my auto bilge to the isolated switch panel for manual use the third wire for auto use i put a fused crocodile clip on if for any reason i leave it afloat overnight i turn the isolator off and put the crocodile clip on the pos terminal of the battery simple and works fine when not using it the crocodile clip clips onto the plastic battery tray

That seems like a sensible idea.

[Pikey Dave]

Originally Posted by Salty Pete

This is my opinion.



- Obviously need to bypass main isolation switch. No! An isolation switch is used on a boat because of the moisture around wiring that will drain the battery. Connecting before the isolation switch negates the reason for having one.

I’ve read that several times & I’m still not 100% on what you’re saying.
Do you mean:-

A) do not feed the pump from the incoming (live) side of the isolator.

B) feed the pump from the outgoing (switched) side

Convention has it, that bilge pumps are fed either directly from the battery, or from the live (incoming) side of the isolator.

[Salty Pete]

Hello Pikey Dave

Nice to see you again.

The OP said that he bypasses the isolating switch. I assume he means that he wires his bilge pump directly to the battery. The reason why we have an isolating switch on a boat is because of the seepage of current between terminals because of the moist environment.

A bilge pump is probably the most moist in a boat and is likely to drain the battery after the isolating switch is turned off.

Mine comes out of the fuse box with everything else and I don't understand why you would want to wire it separately.

[Orwell boy]

Originally Posted by Salty Pete

Hello Pikey D

Mine comes out of the fuse box with everything else and I don't understand why you would want to wire it separately.

Well that would be because when left unattended the switch in the off position ,after a few rain or snow showers the boat will begin to fill with water ,with no possibility of the auto bilge pump starting up the boat will just keep filling up !!

Maybe think of the first leg of wiring just going to the isolated pole of a float /level switch ,maybe removes the need for discussion as float switch doubles as individual automatic battery isolator for bilge pump wired directly to the battery or the pre switched side of main isolator ,(bear in mind the level switch is usually contained within the pump but if you think of it as a seperate item it makes it simpler to see the logic )

[Salty Pete]

Hi there Orwell boy

It was rather short sighted of me not to take our geographical locations into consideration.

I see people in photos from your location, England, Britain or UK, whatever and they are out in their RIBs wearing a huge jacket and beanie and probably thermal knickers. And they are heading out into monstrous waves.

Over here we wear frilly knickers and a tee shirt if it's cold. and, any more than a ripple we stay home.

The only liquid we get in the bottom of our boat is when we spill a beer.

But seriously folks, the OP didn't mention that he was going to leave the boat unattended. For the reason of not flattening batteries bilge pumps have been designed using a pendulum arrangement worked off the rocking of the boat and also wind generation to recharge the battery.

Of course over here we use solar power (runs off the Red thing we have in the sky here)

See ya Orwell boy have a nice day.

[Orwell boy]

Originally Posted by Salty Pete

Hi there Orwell boy

It was rather short sighted of me not to take our geographical locations into consideration.

I see people in photos from your location, England, Britain or UK, whatever and they are out in their RIBs wearing a huge jacket and beanie and probably thermal knickers. And they are heading out into monstrous waves.

Over here we wear frilly knickers and a tee shirt if it's cold. and, any more than a ripple we stay home.

The only liquid we get in the bottom of our boat is when we spill a beer.

But seriously folks, the OP didn't mention that he was going to leave the boat unattended. For the reason of not flattening batteries bilge pumps have been designed using a pendulum arrangement worked off the rocking of the boat and also wind generation to recharge the battery.

Of course over here we use solar power (runs off the Red thing we have in the sky here)

See ya Orwell boy have a nice day.

Ha Ha ,well spotted Salty , just a window into your culture there ! beer and a tee shirt ,ours is more grow a beard for protection against the salt blast ,and pumping your boat out when you get to it is all part of that hunter /gatherer culture ,much of our hobby goes on in the back garden fettling the trailer ,or fitting new bits to ensure our next trip will be trouble free as our availiable days are far fewer so all need to count.

[Pikey Dave]

Originally Posted by Salty Pete

Hello Pikey Dave



Nice to see you again.



The OP said that he bypasses the isolating switch. I assume he means that he wires his bilge pump directly to the battery. The reason why we have an isolating switch on a boat is because of the seepage of current between terminals because of the moist environment.



A bilge pump is probably the most moist in a boat and is likely to drain the battery after the isolating switch is turned off.



Mine comes out of the fuse box with everything else and I don't understand why you would want to wire it separately.

https://www.bluesea.com/systems/42/2...ctrical_System

[Bjohnson]

Originally Posted by Pikey Dave

I’ve read that several times & I’m still not 100% on what you’re saying.
Do you mean:-

A) do not feed the pump from the incoming (live) side of the isolator.

B) feed the pump from the outgoing (switched) side

Convention has it, that bilge pumps are fed either directly from the battery, or from the live (incoming) side of the isolator.

So I should expand a little on my original post;

Boat has only single battery system. Boat is normally kept ashore, but a handful of times through the year i will leave it in the water over a weekend. Currently have a bilge pump, but its manual only, switch on my control panel to operate it.

The winter upgrade is to fit a new (and separate) console mounted Auto/Off/Manual switch, plus a new auto bilge pump. When the boat is left in the water, i can leave the switch in auto and any water will hopefully be pumped out.

The reason for the origin of supply, as noted by PikeyDave above) is that with the main isolator off when leaving the boat, the bilge pump can continue to operate. This was my interpretation of having a separate Auto/Off/Manual switch, rather than route the supply via the on board switch panel.

Happy to be guided and wasn’t completely clear what the ‘best practice’ approach should be, given that I’m going to the trouble of fitting a whole new system (pump, wiring and switch).

[GuyC]

If you take Battery 1 and the ACR out of the drawing that PD has linked to, that will act as a good guide as to what to do.

[Bjohnson]

Originally Posted by GuyC

If you take Battery 1 and the ACR out of the drawing that PD has linked to, that will act as a good guide as to what to do.

Got it, thanks. Supply off fused block (which i have under the console) to bilge pump. Isolator stays on when left in water, but ensure everything else switched off to prevent battery drain.

[Pikey Dave]

Originally Posted by Bjohnson

Got it, thanks. Supply off fused block (which i have under the console) to bilge pump. Isolator stays on when left in water, but ensure everything else switched off to prevent battery drain.

The only danger from this, is that you arrive at the boat after a wet night & the starter battery is flat. Just something to consider.

[_monkey]

Originally Posted by Bjohnson

Got it, thanks. Supply off fused block (which i have under the console) to bilge pump. Isolator stays on when left in water, but ensure everything else switched off to prevent battery drain.

I used one of these on the higher bilge pump:
https://seamarknunn.com/acatalog/Att...BoCNSwQAvD_BwE

It's connected to the house battery to avoid flattening the starter.

[GuyC]

Originally Posted by Bjohnson

Got it, thanks. Supply off fused block (which i have under the console) to bilge pump. Isolator stays on when left in water, but ensure everything else switched off to prevent battery drain.

The isolator can be turned off because the bilge pump is on the 24 hour circuit which bypasses the isolator.

The fuseblock in the picture has two supplies - one from the isolator and one from the battery. You might find your fuseblock has one common supply so you would need a separate fuse block.

[kalin]

You need switch for bilge pump which have 3 positions and fuse.
MANUAL - OFF - AUTO
You need to connect + direct to battery (or before main switch) because if you leave boat you can put to auto if it's necessary (without other electronics) and you are safe.
IT will be safer if pump is connected to 2nd battery not starting battery, if you have choice.

[HDAV]

Originally Posted by Pikey Dave

The only danger from this, is that you arrive at the boat after a wet night & the starter battery is flat. Just something to consider.

But better than arriving to find boat full of water and sinking.....small portable jump pack in car cheaper than a second battery!