Question about slide operations

[jdarwin]

Happy New 2020. I have a 3931FB. I was told by the dealer that the slides run on batteries and when plugged into shore power the 120 is converted to 12vdc to run the slides. Yesterday I had a conversation with a service tech who told me the slides run off batteries 100% of the time. If your batteries are low you’ll need to charge them before operating the slides.

I thought I’d call Keystone but this being New Year’s Day I thought I would ask here first.

[rohrmann]

Your tech told you correctly. The slides are operated with 12 volts. It also doesn’t matter if the slides are hydraulic or electric, they are still 12 volts and should have a fully charged battery to work. The converter can not supply enough current at 12 volts to make the hydraulic slides work properly. I’m not familiar enough to say how much current is needed for cable slides, but I’m sure they will operate much better with a fully charged battery also.

[jdarwin]

Appreciate your feedback.

[Daryles]

You probably have a 50A fuse running the hydraulic pump. LCI bulletins advise upgrade to 80A. Something to do down the road unless you have problems before then (hardly works in cold weather).

[jeffba]

If the batteries are a little low, plugging it in will help as the converter will supply some additional current. It is not enough to supply it all

[scottz]

Your tech was correct, the slides (and other things) run off the 12V batteries. The converter, when supplied with shore power, charges the batteries.

Think of your batteries as a pitcher of water or the water behind a dam. The water (voltage) is the potential used to power things. As you run DC devices (including slides), the level gets lower. The converter (or your truck while driving or solar panels if you have them) refills the pitcher (current); sometimes it can't keep up.

[Mikendebbie]

I have a self-imposed policy that I do not want to operate the slides until I am plugged in to shore power. I have installed the 80 amp breaker on the slide circuit, but on 3 or 4 occasions over the past year it has been a close call as to whether the slideouts were going to complete the cycle and close...watching the battery voltage drop down into the 12s and saying a prayer plus whispering sweet nothings to the slides (come on now-be a good boy and close up snug). The last time it happened was several months ago and we had stopped at gas station so I could run the slides out and get to the cabinet with dog food in it. We had been driving and the batteries had a good charge but even the 80 amp breaker popped. I was able to get them in finally but I decided right there that I would not do that again unless it can’t be helped. I have not had any issues when I am plugged into shore power. I now keep the dog food in a cabinet that can be accessed without moving the slides.

[paulinbaja]

Having the tow vehicle connected and RUNNING will help. When I park I attempt to slide out before disconnecting from the truck. If shore powered I pull slides in before unplugging. One battery alone should be enough but usually proves insufficient.

[Richard Blackwell]

We do a LOT of "road-tripping"...and plugging into shore power is the FIRST thing done anywhere we stop for overnight or longer and the LAST thing to be undone when leaving. This assures we're not stressing out the battery as much with heavy discharging.

[jcurryii]

Agree with Paulinbaha. Had a RV in a park we were at, that battery was dead and could not open his slides(after being left unhooked at park for some period of time). Hooked up to tv with engine running and opened the slides. New battery fixed.

[plgavin]

We had sluggish slide issues boondocking our first year in the Monty. After a trip to the dealer for another matter, I was told it would be best to add another battery. While setting this up I found the factory connection to the battery had a loose crimp on neg cable going to the frame so I replaced both cables using a heavier gauge to be sure. Just replacing the cable fixed my problem. I do connect shore power first, when available, as mentioned by others.

[richfaa]

We do like MIKENDEBBIE always have. "I have a self-imposed policy that I do not want to operate the slides until I am plugged in to shore power."

[beeje]

Originally Posted by rohrmann

Your tech told you correctly. The slides are operated with 12 volts. It also doesn’t matter if the slides are hydraulic or electric, they are still 12 volts and should have a fully charged battery to work. The converter can not supply enough current at 12 volts to make the hydraulic slides work properly. I’m not familiar enough to say how much current is needed for cable slides, but I’m sure they will operate much better with a fully charged battery also.

I am trying hard not to disagree with your statement, but I have to disagree. I have 4 batteries 2- 12 volt and 2_6volt wired together (always fully charged). The only time my slides have tripped the breaker is when I am not plugged in or hooked up to the genny and running on only battery power. IMHO being plugged in creates enough 12 volt power from the converter to operate the slides without tripping the breaker.

I just recently upgraded to the 80 amp breaker. No time to test though.

[Carl n Susan]

Remember the 12V feed to the pump and the 12V feed to/from the converter are both on the load side of the CB. There is no way the converter output can trip the CB when running the pump. Having shore power, converted to 12V to the pump, reduces the amount of current coming from the battery through the CB to the pump.



I can tell you that if you run those three sets of 12 Vbatteries down far enough, the converter can put out enough amps charging the batteries that a weak CB will trip just like when running the slides. Ask me how I know.

[DebNJim B]

Originally Posted by Mikendebbie

I have a self-imposed policy that I do not want to operate the slides until I am plugged in to shore power. I have installed the 80 amp breaker on the slide circuit, but on 3 or 4 occasions over the past year it has been a close call as to whether the slideouts were going to complete the cycle and close...watching the battery voltage drop down into the 12s and saying a prayer plus whispering sweet nothings to the slides (come on now-be a good boy and close up snug). The last time it happened was several months ago and we had stopped at gas station so I could run the slides out and get to the cabinet with dog food in it. We had been driving and the batteries had a good charge but even the 80 amp breaker popped. I was able to get them in finally but I decided right there that I would not do that again unless it can’t be helped. I have not had any issues when I am plugged into shore power. I now keep the dog food in a cabinet that can be accessed without moving the slides.

You might want to have your batteries load tested. You shouldn't have any issue cycling one slide off the battery alone. I still have the cheap single battery the dealer provided and can cycle all six of my slides on the battery with out TV or shore power.

[paulinbaja]

The concept of load checking batteries is good. BUT using the jacks and running the slides are heavy draws. If boon docking every ounce remaining in the batteries is important. I suggest doing the jacks and slides while the tow vehicle is still connected and running, and maybe running for a few more minutes.