Can I connect a 12V hoist pump across 24V on my bobbed M35 dump conversion.????

[ballencd]

When I converted my bobbed M35 to a dump I installed a 12V hoist pump (on one battery) since I could not find a 24V pump at the time. (the pump was included in the kit) I have had pretty good luck with it but when I am busy moving dirt I run the one battery down and have started charging the battery while I am loading with a 120V battery charger. This works OK but only marginally....the pump takes about 42-45 seconds to dump and then almost that to lower the bed after the dump and it is a real pain to plug in the charger after every load. I forgot once and ran over the charger also allowing me to get a new charger! : (

Somewhere in the dump conversion threads I read while I was building the dump I found a thread where the user said something like "I installed a 12V pump on my 24V truck and it has run fine for 7 years" or something to that effect. At the time I read it I assumed he had connected the pump to one battery like I had but have been thinking if that is really what he did??? My question is: "Does anyone remember this thread or know what would happen if I connected the 12V pump across the 24V batteries?" I am thinking back to the 60's when I converted a VW from 6V to 12V and used the 6V starter with no problems. The starter ran faster but didn't burn up.

 

[Westech]

Simple answer ... No

 

[Westech]

Get a 3rd battery snd a 24-12 volt inverter. A member is selling a 100 amp unit for 200 bucks

 

[gimpyrobb]

Can't hurt to try it.

 

[porkysplace]

Can't hurt to try it.

Video required ? opcorn:

 

[5ton toys]

you could hook a 6volt to 12volt due to the heavy windings in a 6 volt won't work on 12 to 24. you can get a 24v motor for your pump from any good starter re-builder hope this helps

 

[glassk]

http://www.steelsoldiers.com/showthread.php?61234-12v-winch-on-24v

 

[gimpyrobb]

I'd do it and not think twice. I'm using a horrible freight 12v winch on 24v and it works just fine.

If memory serves me, depending on how the motor is made, it will either run cooler or faster. I read a lot on the subject a long time ago. Some of the info stayed, most left!

 

[JH1]

Check MPJA.com for a selection of 24v to 12v down-converters. They won't put out enough current to run a hydraulic pump, but you can charge that third 12v battery with it as needed. I think you can set the output up from 12 to 13.8 or whatever. Might have to hack it with a couple of resistors. The 12v pump will work great for a short while. Emphasis on the word 'short'. Btw, if all you're going to do is recharge the battery between dumps, you don't need a 200 amp job. A 20 amp downconverter should be fine, so long as you're running the truck at least a half hour or so between dumps. I agree with someone above that you should just replace the pump motor with a 24v one. Simpler solution.

 

[USAFSS-ColdWarrior]

Asymmetrical loading/charging WILL destroy your batteries as your charging system will overcharge your lightly loaded battery, while trying to catch up on the drained one you've loaded up with "extras". Eventually you WILL also risk loss of your voltage regulation circuit and your alternator/generator power source as well.

MANY fire departments have electrical problems on their former military 24V systems because of 12V equipment sabotaging their "best intentions."

We got our deuce from one such VFD and ultimately had to have the aftermarket DELCO Alternator rebuilt, and two fresh military issue batteries replaced. The cost of their ill-advised electrical engineering was far more than the cost of DOING IT RIGHT THE FIRST TIME.

Carry on.

 

[ballencd]

Looks like I wait for the PTO powered solution. I have plans for a hydro winch in the future anyway. Just trying to speed it up but not at the expense of having to replace the pump in short order. Meanwhile, I will keep charging the battery from house current. Thanks

 

[ah64pilot]

You run off one battery yes and it is one of the two in series for 24V. Take a volt meter and check if you put the probes across the two terminals for the truck you get 24V. Now put the probes across just one battery you have your 12V I have bee putting 12V accessories on all my Mil equipment this way. My fans have clips so I can swap between vehicles.

 

[gimpyrobb]

Thats a bad idea especially for a winch.

 

[Jeepsinker]

Yes that is a good way to destroy a battery over time.

 

[ah64pilot]

Yes if you have a very high draw. That Can be read with a AMP Probe. Even then you can rotate the leads of the batteries. We done this in AFG to run stereo's and everything else that the soldiers could get there hands on. The best is to get the right equipment! I agree.

 

[m16ty]

A hyd pump is considered a high amp draw.

Actually, any draw at all on just one battery shortens the life of the battery. The larger the draw just means the damage happens faster. Very small draws may be negligible but it will shorten battery life.

 

[m-35tom]

the larger the pump motor the better it will be, but the short answer is that you CAN run a 12v motor on 24v and it will not mind in situations where the run time is short. the current draw will be higher, but still not a problem. i would suggest you use a 24v solenoid to control the motor as the 12v coil will not like it and burn up. if you run the motor for 1 minute, i would give it 30 to cool down, this should last for many years.

 

[gimpyrobb]

Tom, at twice the voltage, wouldn't the current draw be half?

 

[m-35tom]

Tom, at twice the voltage, wouldn't the current draw be half?

you are thinking about constant wattage. this starts out being a resistive load but quickly becomes an inductive load so the current starts out at double but quickly drops to more than what it would be at 12 volts but not enough to be a problem.

 

[zout]

There is gobs of information existing from the RV world just about the set up - I am not mentioning usage but just the setup of voltage usage off 12-24 voltages and batteries - short and simple readers digest version is don't do it. Inverters or separate battery just kept charged by itself are few of the options.

12 deep cycle battery over a normal automotive battery would be the choice and only charged on low amp - not from a normal battery charger.