Can I use a small battery jumper to extend and retract RV jacks?

Dear Dave,
I will be moving my 5th wheel to another storage location that doesn’t have electricity available to charge the battery. What size of jump starter would you suggest to use for operating my stabilizers at the storage? —Dale, 2012 Sierra C Class 3440BH

Dear Dale,
This is a very interesting question which has several variables. I first received this question from Chuck Woodbury, Publisher of RVtravel.com, as he posted it to AI and asked my thoughts on its answer.

Here is what he got from ChatGPT

For operating your stabilizers at a storage facility without electricity, you’ll need a portable jump starter with enough capacity to power the stabilizers’ 12V DC system. The typical stabilizer system draws around 10-15 amps when in use, but it may depend on your specific model.

Here are some recommendations:

Capacity (Amperage): Aim for a jump starter with at least a 400-600 amp peak rating. This should be enough to power the stabilizers for a short period, like the time it takes to level the 5th wheel.

Amp-Hours (AH): To determine how long the jump starter will last, check the amp-hour rating of the jump starter. For a stabilizer that uses about 10-15 amps, a battery with around 15-20 amp-hours should suffice for a few cycles of use, though you’ll want a jump starter with a little extra margin in case other accessories are drawing power.

Extra Features: Some jump starters also come with built-in air compressors, USB ports, or even inverter functions to provide additional utility.

If you’re only using it for stabilizer operation, a smaller, more compact jump starter would likely work fine. Just be sure it’s rated for at least 12V output with the peak amps and capacity mentioned above to avoid running out of power quickly.

Would you like recommendations for specific jump starter models that would fit this purpose?

Back to Dave

Let me start by stating that I am not against Artificial Intelligence (AI). In fact, many of my high school teachers claimed my intelligence was artificial! I believe AI is no different than when we manually search the internet researching products or issues and educate ourselves.

Artificial Intelligence can fall short

However, keep in mind anyone can write anything they want on the internet and there is a spellcheck feature in MS Word, but there is no fact check button, and this is where I feel AI falls short. It scans the thousands of articles and posts on a subject and copies the top of the heap. I do not use AI; however, I do use internet searches to help research and then contact the actual manufacturers, technicians, or qualified sources.

I personally have a NOCO 1000A battery booster and just recently got an AstroAI 4000A booster to do a product demonstration on. Since it is winter here in Northern Iowa, I had not yet used the AstroAI version. However, this question sparked my interest, so I did some research.

The NOCO 1000A is rated for 12V and 2150 mAh, which is actually only 2.15 Ah. I doubt that would be sufficient to retract and extend all four levelers on the rig. The smaller 400-600 Ah recommended by AI would be even less. The 4000A version has an Ah rating of 20000 mAh, which would be 20 Ah and might be sufficient.

I personally have witnessed dealers using these jump starters during setup and tear down at shows to bring out slide rooms and extend jacks before the electrical lines get run to the rigs. At the time, I did not think much of it. However, I do believe most of the trailers did not have batteries at all since they are typically delivered with no battery and left for the dealer to decide what type the owner needs.

Disclaimer from Battle Born Batteries

So I did a little research and found that Battle Born^® has a disclaimer on their website that states:

In addition, you should never jump-start deep cycle batteries of any variety. The jumping process should only be used when quick bursts of energy are needed to get a motor or other device going. To revive a deep-cycle battery, use a battery charger to recharge the battery per manufacturer specifications.

I was not able to talk directly with anyone from Battle Born prior to this post. However, I did contact several other battery experts and found some interesting thoughts:

From Dennis, my “all things 12V ‘go to’ guy”:

Jump starters are designed to provide instantaneous high current for a very short period of time. For a starter battery, this is known as “cranking amps”. Normally this high energy drain lasts a few seconds. Continuous jumping can quickly discharge the internal battery. Continuous rapid discharge may cause the battery to overheat and damage the battery.

140 Amps of discharge for 30 seconds has the equivalent energy consumption as 2 seconds of 2000 amp cranking but the heating factor at 140A/30 sec will be greater.

I would verify with the jump starter manufacturer if their unit will provide a sustained 140 Amp draw and would this type of use void any warranty.

Back to Dave

So I did a test with a couple of batteries in my workshop that are almost dead. First, the newer battery chargers and jump starters have a reverse polarity safety feature and if they do not recognize a slight charge or a reverse polarity situation, they will not charge. So, if your battery is completely drained, it will not work.

I did find one of my batteries that had a 2-volt charge and connected the 4000A to that. I got the green light stating it had correct polarity, so I pressed the boost button. As you can see, it provided 16.5 volts.

From Lifeline Batteries

Next, I went to my Lifeline Batteries technical contact. I feel Lifeline makes some of the best Flooded Lead Acid (FLA) and Absorbed Glass Mat (AGM) batteries in the industry. He stated the same concern as Dennis, as the initial boost will be a high voltage charge for a short amount of time. That is good for a Cold Cranking Amp (CCA) engine battery but not a deep cycle battery. If the battery is discharged below 50% SOC (State of Charge), it is designed to have a low voltage charge for a specific time to bring it up to a reasonable charging stage, rather than a high voltage boost which could ruin the battery.

Since they are not in the lithium market, he did not have much information. However, he did state that most lithium batteries want 14.6 volts. 16.5 volts would send the Battery Management System (BMS), which is the integrated computer, into “Danger Will Robinson” mode. (My term, not his!)

What type of levelers?

Dale stated that he was going to move his 5th wheel trailer; however, his vehicle description stated Class C (although the Sierra 3440BH is a fifth wheel). I’ll assume this was a typo and the unit is a 5th wheel, as a Class C engine could be started and the engine charging system would operate the jacks through the Battery Isolation Manager (BIM).

Most trailers these days use the Lippert hydraulic jack system called Ground Control. According to etrailer.com, one of their distributors, they can draw the following amps:

The power circuit for each leg of the Lippert Ground Control leveling system #LC358590 is protected by a 35-amp fuse. That means that, at most, the entire unit could draw up to 140 amps at a time. Realistically, it would probably be considerably less, but that really depends on the weight of the trailer.

Keep in mind that a 5th wheel can weigh anywhere from 10,000 – 14,999 lbs. dry. So the jacks will have substantial weight on them, especially the front. Plus, there could be four or even six jacks on a 5th wheel.

So I guess to be safe, you could use the higher powered battery pack or jump starter for the jacks, but disconnect the cables from the battery and clamp directly on the cables.

Another alternative

The jacks are powered by the house batteries, which can be recharged by the tow vehicle charging system through the 7-pin electrical connection. When Dale hooks up the rig to move it, the engine alternator will provide enough power to retract the levelers. When he gets to the new storage facility, the house batteries should be fully charged. Just verify the 12V alternator wiring is connected, as some trucks are delivered without the fuse installed.

AGM batteries will naturally drain in about 6-8 weeks or more, and lithium will hold a 90% State Of Charge (SOC) for 6+ months.

If you’re in the area, be sure to attend Dave’s seminars at the Pennsylvania RV Supershow today through Sunday. You’ll be educated and entertained, guaranteed!

 You might also enjoy this from Dave 

Powering your RV: Essential 120-volt electricity tips and gadgets for every RVer

This is Part 3 of Dave Solberg’s “Everything you need to know about RVing” series. Today, Dave looks at 120-volt electricity and tells you just about everything you need to know.

MORE INTERESTING POSTS FROM DAVE ON RV ELECTRICITY

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• Some fun facts I learned about electricity this week
• Should I upgrade RV house battery system to 48-volt for boondocking?
• Do I need to keep my stored trailer plugged in?
• How does a 50-amp to 30-amp adapter work?

Dave Solberg is a leading expert in the RV industry and the author of the “RV Handbook.”

Read more from Dave here. 

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