can a rechargeable 12v battery power a pump?

[nancyk]

can a 2.2 Gal. per minute 12-Volt pump on a 3 pt sprayer (Workhorse 40 gal 12 volt with 5 nozzle boom for utility tractors) be powered by a 12v 35Ah rechargeable battery? This sprayer has not yet arrived but I already know the wiring harness is 8 ft long and will not reach the battery in front of the tractor. It will eventually be wired to a 7 pin connector to be powered from the back of the tractor at the seven terminal outlet and hope to get that also connected to an off/on switch to be used from the tractor seat. I have some rechargeable batteries I use for my front gate opener and could use one temporarily until we get the wiring done.

Nancy

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[bearthebruce]

Looking at the Workhorse spec, the current draw of the motor is less than 7.5 amps as determined by the recommended fuse. They actually give nothing about typical running current.

What type battery are these rechargeable batteries? NiCads? Or Lithium Ion? The battery type matters.

My guess is that if you run from full charge, you might get 2-3 hours of proper operation. Going just by amp hour capacity not knowing the battery construction, let's assume the motor needs 6 amps at 12 volts to run full speed and do its job. Lets also assume the battery will hold the voltage to around 12 volts until it is about 50% discharged. That means you would have 16-17 amp hours of use. At a 6 amp draw, you will hit 50% discharge within 3 hours.

In real life, the voltage will sag as the battery discharges so the motor will slow. As the motor slows down, you will loose pressure and the spray will not be applying at the rate you need.

It worth an experiment I suppose... but may destroy the batteries in the process.

Wouldn't it be better to run a temporary wire to the tractor battery distribution panel? Use a heavy duty electrical cord and tie it up so it does not get caught on anything until you can make your permanent installation?

The difference being the tractor's alternator/generator will carry the load more than the battery.

 

[nancyk]

"may destroy the batteries in the process." that is what I am concerned about. The batteries I would like to use, temporarily, are the ones I use for my gate opener, which has a solar panel to recharge. However, for the past 3 years it has not been recharging so I exchange the batteries every three weeks, then do a trickle charge for the day, and am set to go. When I get this new sprayer system set up I would like to try it out but do not want to make any changes to it(adding a 7 pin connector power system) until I see how it functions. What is the battery distribution panel? I believe, ultimately this sprayer system will suit my needs(spraying a mile of gravel driveway 4x/year), but would like to try it out before altering powering systems.
Batteries are sealed lead acid battery. 7.5" wide x 6" tall x 5" deep.

 

[WranglerX]

JUst wire it to tractor when it arrives and then you don't have to worry about charging/ruining your spare gate battery....

 

[oosik]

I agree with WranglerX. Why try to get exotic when your tractor system can handle it so easily.

 

[zzvyb6]

I have found it works wonderfully with a standard car battery on my AE long wheelbase work cart. I found a RAV4 trailer hitch that fits it perfectly and then found a hitch carrier at an estate sale. It holds a 25 gallon spray tank. The pump is what you have shown and has the on-demand option (runs only when actively spraying). I run 4 spray nozzles at a 4' separation for weed and feed on my lawn. With a hand held wand with a trigger, it will shoot a solid spray more than 20 feet. Since the cart is 48 Volts, it was easier to power it from an extra car battery. Haven't had to recharge the battery yet this year. (The over size load banner is a joke).

 

[nancyk]

"Just wire it to tractor when it arrives" as I do not have the system yet but have looked at what is included with it, I believe it comes with clips to attach to a battery. How can it (easily) be wired to the tractor? I have ordered a Tectran 7-Way SAE Plug with Spring Guard and am hoping my electrician neighbor can set it up for me. He has a lot on his plate so do not know how quickly he will be able to do this.

 

[chim]

The power for my sprayer is via the 12V (aka cigarette lighter) outlet in the cab when using the Kubota. It has an inline switch on the wiring before exiting the cab that's used to switch power to the pump when the spray boom is used.

When using the Ford, it uses a "flat two" trailer connector. The Ford has a rear light on a separate switch that uses the same flat four. Just unplug the light and plug the sprayer in. Light switch controls ON/OFF.

When using the wand, no need to switch because of the on-demand pump. Power to the pump stays on constantly.

 

[nancyk]

As the tractor has no cab, it has no 12v outlet. The current spray system is powered by a plug to the seven terminal outlet on the back of the tractor and is easy to connect and disconnect.

 

[nancyk]

"may destroy the batteries in the process." Just curious, how could this occur? If the 2.2 gpm pump ran continuously while connected to the 12v battery, wouldn't it just drain the battery?