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Running Class A RV Leveling Jacks With A 24v Solar Battery Bank

If I tell my wife that she can't have her coffee because I'm in the middle of an online race in the simulator. She will sell the RV with me in it ?

The battery voltage isn't my limitation. It's that I'm running off of a 15 year old 1000 watt Xantrex inverter that was a hand-me-down. My 12v system can handle a 3000 watt load, perhaps a bit less when the sun goes down, once I upgrade my inverter. I'm running dual 280Ah 4s batteries for 560Ah, with a 120 amp BMS on each battery.
 
Having worked with 12vdc hydraulics and the pumps be inductive devices, there are some things you need to think about besides how much current it draws when running. These pump motors have a startup current (inrush) draw of about 3 times the running current. If you have the pump connected directly to the converter, the pump will probably have an intintanious draw that exceedes the outputof the converter. As far as I'm concerned the pump need to be connected to a battery and I dont think a Lifepo4 would do the job unless you had a number of them parralled so you dont exceex BMS.

I have a class A Itasca and my leveling system must have the engine running. Not sure what batteries pump is connected to but I suspect it's the chassis battery. Would not want pump on house batteries and have the pump partially run down my house batteries when I first park, using up that precious power.
In my case, Thor wired the hydraulic pump directly to the house batteries. I have a Thor Ace 30ft. What you are saying makes total sense to me.

If I can wire the pump directly to the chasis battery I'll be golden i think. Because the converter which is rated for 70a should be able to handle all the remaining 12v loads.
 
That's the same converter I bought. The jacks are not 24v, they are 12v. You have your jacks wired through this converter with no problem? What kind of rig do you have?

When I measured the amp draw while leveling it was mostly constant at around 50 amps but it did jump up to 160 for like a second at one point. That's why i thought i needed something that can handle 160 amps. Can this converter handle that?
I can’t say for sure. I start my 24 volt upgrade in October.

I measured 50 with no spikes. I have 12 k lbs fifth wheel. For my first trip, if the 70 amp won’t supply power, I have a socket wrench and extension to raise the jacks manual ally.

I feel like we’re in an area no one has ever done before with ditching the 12 volt battery. I’ve been asking about who’s done it with a rig this size, and no one has given details if they’ve ditched the battery with leveling jacks.

I even looked for 24 volt leveling jacks from lippert. None.
 
I am wondering if they used the 12 volt house battery pack for the power both because it is nearby and 200 amps is a fair amount of current.

It isn't all that easy to efficiently move 200 amps @ 12 volts more that 10 - 15 ft away.

Is there any chance of finding a 120 vac version of the pump? If so, it could then be powered from the house pack / inverter.

I routinely use DC - DC converters in the 30 amp output range for point source power - and they work well. At the same time, some customers have managed to destroy them so I have had to add additional current limit protection to the output.

The converters don't have an instantaneous response. If the motor is pulling anything close to locked rotor amps at turn on, then it may or may not work as well as you hope - or it could just be a lag which is not a big deal.

In the audio world, they would solve this with a big capacitor on the amp but I am not sure about using it that way with a motor.
 
Most Lippert leveling jacks in class C's are connected to house batteries. I've had to disconnect the board before to get the system to reset to be able to use jacks after running house system too low.
 
Yesterday I found the wiring diagram for my coach battery and went ahead and moved some connections around to be able to test running the jack pump off the chasis battery. And it worked, everything seemed to run fine.

Here is the original connections, and the connection I made marked in red.
 

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Most Lippert leveling jacks in class C's are connected to house batteries. I've had to disconnect the board before to get the system to reset to be able to use jacks after running house system too low.
So by all the input I'm getting, it seems like it actually makes more sense to wire the jacks to the chasis battery rather than the house batteries.
 
I don’t recommend wiring these to Chassis Batteries if they are 24 volts. If you do, come back after several months and tell us if the jacks are still working. If 24 volts is a no go, those jacks are very expensive. Someone told me that would work and only spin faster, but I’m not willing To spend my money if he’s wrong Because replacement motors are pricey.

On 24V, a 12V motor runs twice as fast but draws the same number of watts and half the amps for a given load. Back in the day of converting vehicles from 6V to 12V, we would leave the 6V starter in place. Engines would turn twice as fast on the starter, great for cold winter days.

I have measured 50 amps when leveling my jacks. I am going with a 70 amp converter:


That should be good for me. The spec sheet on that DC to DC converter says they can be paralleled together. 160 amps means three of them. One is good for me, but if you truly are pulling 160 amps on a meter form your batteries, than three is an option, but then that is pricey and can take up more room than a battery. If I used three of them, there’s be a switch on two of them and only turn them on when leveling.
 
On 24V, a 12V motor runs twice as fast but draws the same number of watts and half the amps for a given load. Back in the day of converting vehicles from 6V to 12V, we would leave the 6V starter in place. Engines would turn twice as fast on the starter, great for cold winter days.
At $3k+ to replace the system or $140 per motor, I am not brave enough to be the first to try this on my system. THe other electronic components are pretty pricey also. I just replaced the remote leveling panel, and that was over $200. I don’t want to find out what would happen with 24 volts instead of 12.

I do wish LIppert made a 24 volt version. That should half the amperage we’re seeing.
 
Here is the original connections, and the connection I made marked in red.
Is the e-start solinoid an emergency start solinoid? You red line shows that the e-start solinoid would have to be activated for the pump to run. So I would think the the red line should be on the other side of the solinoid.

So this brings up another issue. You won't have an emergency start solution unless you connect into one of the 12vdc batteries of the 24vdc setup. I guess that would work in an emergency unless the 24vdc batteries are lifepo4.
 
At $3k+ to replace the system or $140 per motor, I am not brave enough to be the first to try this on my system. THe other electronic components are pretty pricey also. I just replaced the remote leveling panel, and that was over $200. I don’t want to find out what would happen with 24 volts instead of 12.

I do wish LIppert made a 24 volt version. That should half the amperage we’re seeing.
I wouldn't run it at 24V, just saying what happens with a 12V motor on 24V.
 
Is the e-start solinoid an emergency start solinoid? You red line shows that the e-start solinoid would have to be activated for the pump to run. So I would think the the red line should be on the other side of the solinoid.

So this brings up another issue. You won't have an emergency start solution unless you connect into one of the 12vdc batteries of the 24vdc setup. I guess that would work in an emergency unless the 24vdc batteries are lifepo4.
Yes it is, and You are right I missed that.

Do you know of anyway to be able to keep emergency start feature?

Right now I can press a switch in the dash if the chasis battery is dead and start the engine with the house batteries and i would like to keep that feature if possible.
 
Yes it is, and You are right I missed that.

Do you know of anyway to be able to keep emergency start feature?

Right now I can press a switch in the dash if the chasis battery is dead and start the engine with the house batteries and i would like to keep that feature if possible.
One of the many reasons we don't want to make changes that would eliminate the Boost switch we've always had one in each MH and BTW, the switch will work in reverse as well.
 
Could the two 12v jacks just be wired in series or have I had too much caffeine today?
 
Yes it is, and You are right I missed that.

Do you know of anyway to be able to keep emergency start feature?

Right now I can press a switch in the dash if the chasis battery is dead and start the engine with the house batteries and i would like to keep that feature if possible.

Everything in life is a trade off.

This can be mostly solved by using a healthy 120 vac to 12 volt charger and letting it run a few minutes prior t o starting.

A relay can be added to power the charger when needed.

A charger is current limited so a much more reliable approach than connecting the DC - DC converter.
 
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