Running Bilge Pump Automatic Off Multiple Batteries

sasto

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I've been thinking (not always a good thing) the past few weeks about running a float switch off of 2 batteries. My thinking is making a box with diodes so I can run a float switch off of 2 batteries. The battery switch can be turned to the off position, leaving me with 2 batteries to supply voltage to the pump in case of the boat left unattended for a period of time.


What do you think? Has this already been done? I can't think of any reason this couldn't be done. I would ask around the marina for imput, but you guys know I'm off the wall.....these folks don't know it yet! ;)
 

smokeonthewater

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Re: Running Bilge Pump Automatic Off Multiple Batteries

I'm a little disappointed in you sasto.... for a self proclaimed nutjob this idea sounds WAY too normal... LOL

I can't see any reason that it wouldn't work.... Now if you want to complicate it a bit, get another batt switch for the pump and use it with the diodes for a truly complex setup ;)
 

sasto

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Re: Running Bilge Pump Automatic Off Multiple Batteries

You have a point, Kevin. Why not a couple toggle switches.

I've seen more boats go down in a marina than offshore. Sometimes, especially here in FL, a storm will knock all power off the dock. A boat is taking on water. The dedicated battery the pump is connected to fully discharges.

Just thinking. Maybe doing!
 

Fireman431

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Re: Running Bilge Pump Automatic Off Multiple Batteries

Shoot Sasto, if you're gonna do it, go all the way...

Power goes out on the dock...
Battery tender monitors voltage...
Pumps run occasionally, dropping the house voltage to just under 12.0 volts...
Auto start transfer switch detects low battery voltage and initiates auto-start of the on board genset...
Genset runs 30+ minutes to recharge the onboard batteries...
Process starts all over again...

Actually, a simple algorhythm flow chart for a first year engineering student. (would take me 13 years to write it, tho :facepalm)...
 

sasto

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Re: Running Bilge Pump Automatic Off Multiple Batteries

Shoot Sasto, if you're gonna do it, go all the way...
QUOTE]

I have only one problem, Fireman. I don't have space for a generator! :cool:.......I was actually thinking about our Bacala and a couple other small boats in my hands.

Now if I can ever get off this Island I'm stuck on....and head to Radio Shack.

I like your thinkin'! :D
 

fishrdan

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Re: Running Bilge Pump Automatic Off Multiple Batteries

So if I understand what you are proposing, 1 bilge pump with 2 diodes tied to the 12V+ wire, then those 2 diodes going direct to each battery. That sounds simple enough and would work. Though, it's going to draw down each battery at the same rate, so you will eventually have 2 dead batteries. I guess that's better than a sunk boat...

One flaw I see is, what happens if the bilge pump fries, a chunk of debris gets hung up in the impeller or the hose gets clogged up? Even though you now have 2 batteries, they would be useless. I had the bilge pump discharge hose clog up on my boat once and even though the bilge pump was turned on, water was barely trickling out of the thru-hull. We were fighting through heavy seas and didn't notice the problem until the engine died,,, bilge was full of water. It would be better to have 2 bilge pumps, each running off their own battery. I have the bilge pumps configured this way in my boat (now), separate pumps, separate float switches set at different levels, separate hoses, separate thru-hulls, separate batteries.
 

smokeonthewater

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Re: Running Bilge Pump Automatic Off Multiple Batteries

I like how that... a small maintenance pump running off of the start batt(s) and a bigger hail mary pump on the house batts with the float switch a few inches higher..... Maybe wire up an alarm on that one too...
 

Fireman431

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Re: Running Bilge Pump Automatic Off Multiple Batteries

It would be better to have 2 bilge pumps, each running off their own battery. I have the bilge pumps configured this way in my boat (now), separate pumps, separate float switches set at different levels, separate hoses, separate thru-hulls, separate batteries.

I like how that... a small maintenance pump running off of the start batt(s) and a bigger hail mary pump on the house batts with the float switch a few inches higher..... Maybe wire up an alarm on that one too...

These are more of what immediately popped into my head. Spare (larger) bilge pump on the other battery and a high water alarm tied into it as well, so activation of the float switch also sets off an audible warning.
 

sasto

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Re: Running Bilge Pump Automatic Off Multiple Batteries

Dan, Kevin, Fireman......

Very good points on a few things I didn't consider. Now down to just one boat I'm considering installing this whatchamacallit.

Thank You!
 

MH Hawker

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Re: Running Bilge Pump Automatic Off Multiple Batteries

Sasto , your forgetting the most important thing you need to find a LED light up giggle hula girl to mount on the stern some place as a pump on indicator.
 

sasto

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Re: Running Bilge Pump Automatic Off Multiple Batteries

Sasto , your forgetting the most important thing you need to find a LED light up giggle hula girl to mount on the stern some place as a pump on indicator.

Your not going to believe this, MH, but I inherited a boat with a strobe mounted next to the anchor light. This thing would flash when the pump was running. I got rid of it!:facepalm:

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Fireman431

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Re: Running Bilge Pump Automatic Off Multiple Batteries

Sasto , your forgetting the most important thing you need to find a LED light up giggle hula girl to mount on the stern some place as a pump on indicator.

And I would mount the hula girl on a cell phone vibrating spinner so when the high water alarm went off, along with the strobe and the LED eyes, the little hula chickie would spin around like crazy like she was having a seizure. Now..that's fun!
 

sasto

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Re: Running Bilge Pump Automatic Off Multiple Batteries

Just my thought but I'd rather have a redundancy across the entire system with a second bilge pump.

Oh how correct you are, Bubba! It was a thought going thru my head for a couple weeks now. As usual....if my ideas would work, it would already have been done!

And I would mount the hula girl on a cell phone vibrating spinner so when the high water alarm went off, along with the strobe and the LED eyes, the little hula chickie would spin around like crazy like she was having a seizure. Now..that's fun!

Don't tempt me, Fireman.:rolleyes:
 

sasto

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Re: Running Bilge Pump Automatic Off Multiple Batteries

MMMMMmmmmmm, can-deeeeeeeeeeeeeee

whatchamacallit.jpg

Now that's funny...fisherdan.:D I guess somebody really did beat me to my new invention. I'm going to buy one and give it a try. Red to red.....black to black! Looks easy enough for me.:rolleyes:
 

smokeonthewater

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Re: Running Bilge Pump Automatic Off Multiple Batteries

hey sasto, I just had a thought... kind of a hybrid of all the ideas in this thread..... how bout two float switches, one an inch above the other, hooked to different batts and connected to the pump with diodes with a horn or siren on the one mounted higher..... then one batt powers the pump with the other in reserve and if the first goes dead, the water rises just enough to activate the pump and alarm from the reserve batt.
 

sasto

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Re: Running Bilge Pump Automatic Off Multiple Batteries

hey sasto, I just had a thought... kind of a hybrid of all the ideas in this thread..... how bout two float switches, one an inch above the other, hooked to different batts and connected to the pump with diodes with a horn or siren on the one mounted higher..... then one batt powers the pump with the other in reserve and if the first goes dead, the water rises just enough to activate the pump and alarm from the reserve batt.

Good thought....Smoke.

I came upon a situation yesterday where there is a possibility this setup would have worked. I was strolling down the docks and noticed a vessel that appearantly had taken on water during a recent rain and strong winds. I boarded her to find out the aft pump float switch had blown a fuse. I pumped her out manually with no problem.

2 batteries and 2 fuses may have solved this problem.
 
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