Batteries off or bilge pump on?

Iain C

Iain C

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So if your boat is on a swinging mooring, you have 2 batteries, 1 is engine, 2 is domestic, and a wind generator, do you...

a) turn batteries off at the master, close all seacocks and lock up

b) connect the wind generator to battery 2, select battery 2 on the switch, and leave the bilge pump on auto, with the electric bilge pump seacock open (small bore about 12" above the waterline)

B seems to make more sense to me but I've been warned against it. Any thoughts?
 
Iain C said:
So if your boat is on a swinging mooring, you have 2 batteries, 1 is engine, 2 is domestic, and a wind generator, do you...

a) turn batteries off at the master, close all seacocks and lock up

b) connect the wind generator to battery 2, select battery 2 on the switch, and leave the bilge pump on auto, with the electric bilge pump seacock open (small bore about 12" above the waterline)

B seems to make more sense to me but I've been warned against it. Any thoughts?
Click to expand...

take a wire with suitable fuse off of battery 2 with a control switch in the circuit
 
Got to be 'B'........cant see why you would be warned against it ?? If you have water getting into the bilge then you need a system to deal with it. What is the use of an auto bilge pump if it has no power ??? How long are you leaving the boat ??
 
My arrangment is to have the auto bilge pump connected direct to the battery through a circuit breaker. I also have an electro mechanical counter connected across the pump to tel me the number of times the pump turned on during the time I am away. This indicates if the water that my be leekinf in is getting worse.

I also have a small solar panel connected across the battery to try to keep the battery charged. If no power is put into the battery, the battery will go flat and the boat will sink anyway once the battery goes flat.
 
Thanks for the tips all, B it is then.

As it happens, the boat has been on a swinging mooring in Portsmouth harbour for the last month, with all that mad weather, and she was totally bone dry in the bilges (after many years ashore) so I'm chuffed.

Thanks
 
not exactly B)

Wire pump directly to battery 2 via suitable protection as per above posts.

Better to have the selector switch in the OFF position when away. any appliance (e.g. forecabin light) inadvertently left switched on would drain your battery 2, rendering your bilge pump powerless. Can't always rely on the wind to be blowing when you need it.

congratulations on a dry bilge!
 
I have option B but without the wind gen but with 450 amp/hours domestic battery.
There is a maintained supply from the domestic battery that is fused and by-passes the battery switch.
This supplies 2 auto bilge pumps, the eber heater and an alarm system.
If a bilge pump runs or the battery voltage drops below a set level the alarm will send me a text.

Having had to replace most of the contents of the boat following a sinking, I would rather have a flat battery any time.
 
Mine got a foot of water and mud in when I left it for 8 weeks.
\now have your b) except I also have 40 quids worth of ebay SMS alarm, which texts me when the bilge pumps operate.......
 
FullCircle and Cliveg,
can you please give more indications on cheap sms alarms because it seems a great possibility. I guess I need at least a cell telephone powered by boat or internal battery, a sim card, a telephone-somethingelse interface, some subscription to a proper alarm company, etc. At the end it does not sound very cheap.

Thanks in advance
Daniel
 
Question

I have a small solar panel aprox 660X450 do not know the output, conneted to a 160ah battery with crock clips,without a regulator but with a diode

However when I go back to the boat after a winter on the mooring the battery is completly dead. and will not take a charge .there is no water in the bilge so it is not the pump discharging it ,this has happend for the last 4 years WHY?

cheers bobt
 
hijack.gif

That I would estimate to be a 30 watt panel. (not so small!) Much larger than necessary just to maintain a battery that has no drain. It ought to be connected via a regulator but thats not the cause of your trouble unless you are running your battery electrolyte right down due to overcharging from such a large unregulated panel


Difficult to guess what the trouble is.

Check for drain on the system with an ammeter. Main isolator off .. just the auto bilge pump left on


Disconnect the panel and check the output volts on a bright day without the diode and again with the diode (I take it that it is a panel that does not have a built in diode)
Should see figures well in excess of 12 volts, shoud be 18 or more in bright sun.

Connect a 12 volt bulb and check that it will light a small one in bright light and a larger one in bright sun (a 25 watt one perhaps but full brightness might be a bit optimistic)

reconnect to the battery, (without the diode) with an ammeter in the circuit making sure polarity of panel is correct.

Put the diode back in making sure the polarity is correct, and check with ammeter again.

Are you saying you have to replace the battery every year. If so are you in fact simply overchaging to the point that you are losing all the electrolyte. Not likely even with a 30 watt panel I would have thought.
 
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Vic
IMHO 1bobt is definitely overcharging his battery with that arrangement.

I have a similar setup for my engine start battery but 40 watt and I fitted one of the regulators from maplin the refueler recommended.


Below is my setup for twin auto bilge pumps. connected directly to my domestic battery sets

The counters are to determine how often the pumps switch on to help indicate the extent of the leakage
 
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Rogershaw said:
Vic
IMHO 1bobt is definitely overcharging his battery with that arrangement.

I have a similar setup for my engine start battery but 40 watt and I fitted one of the regulators from maplin the refueler recommended.
Click to expand...


Done some calculations of the water that would be lost from the battery. Arrived at just over 60cm³ per cell in 1 year if there was a current of 0.5 amps flowing (into a charged battery) for 4 hours per day for 365 days. You could live with that but much more (due to a higher current or more hours) then the water loss would be excessive.

I agree with Roger it does need a regulator. Usual rule of thumb is that 1 watt of solar power per 10Ah of battery capacity does not require a regulator but more than that does. Also it is usually recommended that solar panels larger than 10 watts should have a regulator anyway.
 
VicS said:
Done some calculations of the water that would be lost from the battery. Arrived at just over 60cm³ per cell in 1 year if there was a current of 0.5 amps flowing (into a charged battery) for 4 hours per day for 365 days. You could live with that but much more (due to a higher current or more hours) then the water loss would be excessive.

I agree with Roger it does need a regulator. Usual rule of thumb is that 1 watt of solar power per 10Ah of battery capacity does not require a regulator but more than that does. Also it is usually recommended that solar panels larger than 10 watts should have a regulator anyway.
Click to expand...


Thanks for the answers
All though the battery is not low on water still above the plates .when ive gone back after 7month of winter layup the battery is just dead. I have a friend who ownes a garage in Poros and he cannot recharge it on his garage battery charger
Every other thing on the boat is isolated. I just have a fused feed to bilge pump .
There is no water in the boat, never has been .The pump is only there "in case"
cheers bobt
 
1bobt said:
Thanks for the answers
All though the battery is not low on water still above the plates .when ive gone back after 7month of winter layup the battery is just dead. I have a friend who ownes a garage in Poros and he cannot recharge it on his garage battery charger
Every other thing on the boat is isolated. I just have a fused feed to bilge pump .
There is no water in the boat, never has been .The pump is only there "in case"
cheers bobt
Click to expand...

appears your battery is being drained and not getting it's trickle charge.
either your seeing leaking current on your bilge pump arrangement and/or your solar panel isn't outputing.

Disconnect bilge pump at battery and measure resistance across the bilge pump curcuit as Vic suggests. Should be "opened circuited".

Disconnect solar panel from battery & measure the panels open circuit voltage in daylight. take diode out. should be >12V. How old is solar panel. you got any specifications for the unit?

Double check that the diode has been wired correctly. (reverse biased with respect to the battery)

assuming zero current drain or trickle charge, could be that your battery is discharging naturally over 7 monhts. can't understand why you can't get some chrge back in on the bench. are you replacing new batteries each time?
 
The problem with option B is "Will you still have anodes and prop left next year?"
Go with a protected line direct and and pump in auto. Switch off battery isolator.
 
danielefua said:
FullCircle and Cliveg,
can you please give more indications on cheap sms alarms because it seems a great possibility.
Daniel
Click to expand...

Daniel

The system I have was developed a few years ago and the production was abandoned. I obtained the last one available from JG Tech.
It has the guts of a simple Cell Phone within it.
it is running a pay as you go sim.
The system is powered by the boat battery.
it only takes miliamps unless it is making a call.
I do like to keep the battery topped up by running the engine every few weeks or connecting a charger to shore power.
The 1st option is not a chore during the summer:) and the boat is at home for the winter and is connected to shore power.

There was a company at the Southampton Show offering a similar kit for around £600.

I think that FullCircle has obtained a system from Ebay for a lot less that that.
Search GSM Alarm

lenseman of this parish is offering something of the kind if you look at his Signature.
 
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