12v Pump & Battery Q.

Might sound silly, and it's just to make sure I don't ruin my equipment but,

Is there any reason, apart from a quicker flat battery, why you can't hook up 2 12v bilge pumps to a single battery?
Looking to run extra water volume or a different water pressures to assist in breaking up soil through the sluice.

Do have 2 batteries but 1's ex auto so a bit heavy.

Cheers T.

Oh, and just cleaning up my gear .... how have I ended up with 7 pans, bastards must breed.

Sounds like you'll be better off using one of them pans. :goldpan:

EVIE/BEE said:

Sounds like you'll be better off using one of them pans. :goldpan:

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Yep, they come in handy when cleaning up .......

You would need to connect the two pumps in parallel, which would keep 12 volts available to each pump, don't connect in series as you would split the voltage in two
getting 6 volt per pump. Can supply a sketch drawing if you need it. PM me.

Swinging & digging said:

You would need to connect the two pumps in parallel, which would keep 12 volts available to each pump, don't connect in series as you would split the voltage in two
getting 6 volt per pump. Can supply a sketch drawing if you need it. PM me.

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Series with 12V DC? Getting 6V?
Think you can explain how this is possible.?..

no issue at all Teemore, just means you'll drain the battery quicker using two pumps.

A roll up 12V solar charge panel maybe a good option for you.. charge while pumping. There's a bunch of sizes available, all with different charge ratings, obviously the higher charge rating the better but that usually means bigger (heavier) panel. Search eBay

Swinging & digging said:

You would need to connect the two pumps in parallel, which would keep 12 volts available to each pump, don't connect in series as you would split the voltage in two
getting 6 volt per pump. Can supply a sketch drawing if you need it. PM me.

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So 2x pos 2x neg direct from the battery is how I understand that.

Dosent make any difference with DC.

Swinging & digging said:

You would need to connect the two pumps in parallel, which would keep 12 volts available to each pump, don't connect in series as you would split the voltage in two
getting 6 volt per pump. Can supply a sketch drawing if you need it. PM me.

Click to expand...

Can you show us how 6V is possible????

A dc pump in and of itself adds resistance Meaning if you have 2 pumps in series there is double the overall resistance meaning the voltage is halved. More resistance = less flow of voltage... try it with a voltmeter...

Series = battery positive to pump1 positive, pump1 negative to pump2 positive, pump2 negative to battery negative

I'm interested in the science of it.
Never thought a 5amp bilge pump could have such with a decent 12V battery.
Have to pick the brains of a an auto electrician .

mudgee hunter said:

Swinging & digging said:

You would need to connect the two pumps in parallel, which would keep 12 volts available to each pump, don't connect in series as you would split the voltage in two
getting 6 volt per pump. Can supply a sketch drawing if you need it. PM me.

Click to expand...

Can you show us how 6V is possible????

Click to expand...

If connected in series two pumps the same will have equal resistance, so 1/2 the voltage would be dropped against each pump. Connecting in parallel the voltage remains the same. For a 5 amp pump each would draw 5 amps, so the battery would run down twice as quick as only using one. Wattage = Volts by amps, 12 x 5 = 60 watts, x 2 pumps 120 watts.

I can draw a circuit diagram to explain.

See circuit it shows a parallel circuit, the resistors shown can represent the pump windings. The Voltage across each pump is the same and matches the supply voltage.

Teemore said:

Swinging & digging said:

You would need to connect the two pumps in parallel, which would keep 12 volts available to each pump, don't connect in series as you would split the voltage in two
getting 6 volt per pump. Can supply a sketch drawing if you need it. PM me.

Click to expand...

So 2x pos 2x neg direct from the battery is how I understand that.

Click to expand...

Yes you got it.

The diagram you have is in m-amps....

Can you show us Amps and voltage drop in in relation to the topic of such?
I can't seem to grasp it!
Like saying my car has a 12v, 30amp rated fuse for cig lighter via fuse box, but only getting 6v whilst other inputs on same fuse link are linked.

Teemore,
When I read your post it seems to be a question about increasing the pump/pumps efficiency to help with delivery to break up the material you are feeding?
Maybe as per much like how a multi-stage pump works?
Putting your centrifugal pumps in series, or connected too a single pipeline, will let you add the head from each together and meet your high head, low flow system requirements.
This is because the fluid pressure increases as the continuous flow passes through each pump.
Of course each pump will be wired parallel and draw equal amps from your battery halving the battery life.

mudgee hunter said:

The diagram you have is in m-amps....

Can you show us Amps and voltage drop in in relation to the topic of such?
I can't seem to grasp it!
Like saying my car has a 12v, 30amp rated fuse for cig lighter via fuse box, but only getting 6v whilst other inputs on same fuse link are linked.

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Thanks above post, i was going to update the drawing i supplied with what :Y: Mudgee Hunter asked but you beat me to it.

Nightjar said:

to help with delivery to break up the material you are feeding?.

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Yep that's the aim. Obviously a few different ways to approach it, just wanted to be sure that with 2 pumps I didn't ruin anything.

Thanks all for your responses

Teemore said:

Nightjar said:

to help with delivery to break up the material you are feeding?.

Click to expand...

Yep that's the aim. Obviously a few different ways to approach it, just wanted to be sure that with 2 pumps I didn't ruin anything.

Thanks all for your responses

Click to expand...

The circuit diagrams posted above are meant only to clarify the electrical aspects of Series and Parallel combinations from a Voltage/Current viewpoint.

If you are going to use two pumps, you should only use the Parallel connection circuit........connecting electric motors in Series and running them at voltage lower than their rating is fraught with danger....for the electric motors, that is...not you

Apologies if I implied with the diagrams that the pumps could be connected either way........Series connection definitely not recommended.

Does anyone know if a 12-24v pump that is capable of a bit of pressure/ higher efficiency? bilge pumps obviously low pressure...

but if you look at impeller design and housing/motor design it is nothing to write home about... Maybe and ewp25 davies craig?