12-VOLT DUAL BATTERY SETUP | Pete's RV Quick Tips (CC)

[@ruthkuzmanic6813]

Thank you for such a clear explanation. I really appreciate you leaving off the batty containers, as it made it so much clearer to see.

[@petesrvtv]

Happy to help, Ruth!

[@glenntrujillo2719]

Thank you for your simple explanation of how to install two batteries.

[@Jack-Surreal_Panes]

Ahhh.... I got an old camper so new to this. Wondered why a red white wire and black jumper. Cool, thanks. Good info

[@Jack-Surreal_Panes]

What threw me off is the previous folk used a black cable vs red.

[@sandhiller49]

Ive watched multiple videos, Randy you did it so simple and quick, Thank you so much

[@petesrvtv]

Great to hear!

[@brentdreamer2025]

Nice basic set up thanks for the info. I have a battery left over from from my truck that I had to replace and I figured why not drop it onto the RV. We rarely dry camp and I don't plan on keeping the RV for more than a few years so I don't really care about the age of the batteries. Cheers

[@GaugingGadgets]

Awesome video! Thanks for making it so simple!

[@petesrvtv]

Glad it was helpful!

[@susansterling-williams8937]

Thanks so much for this simple explanation. I go camping with my horses where there is no power for days and now have extra power for my camper..

[@Hundert1]

Good demonstration, Thank you

[@craycray9852]

This is so simple to some one who knows. I didn’t know this is the proper way to hook up the batteries to my trailer. Mine kept going bad after 6 months, under warranty, but a pain to take them out and replace them. I almost replace my trailer charger thinking that was the problem. Thank you for marking this video! I understand now how to properly hook my batteries!

[@talibahdivine]

Nice and simple. Straight to the point. Thanks for this video. What are your thoughts on lead batteries vs lithium batteries?

[@Hundert1]

Lithium is better. Sodium is what I'm researching now.

[@fadedexile]

Thanks for the video it's good to know that I did it right 30 minutes before I thought to search for a video about how to do it 🤣

[@petesrvtv]

Happy to help! 😄

[@alularussell778]

Thank you. Your vid has answered several questions I had that nobody else seemed to know.

[@brutallindigo]

Great vid...Question ..Does it need to be the same type of battery?

[@ME-le9hw]

Question about using a larger gauge than what is originally used on the trailer. I disagree with that statement, mainly because the larger the gauge number is equal to a smaller wire. For example, 10 gauge wire is bigger in diameter than a 14 gauge wire. I do agree with hooking up with positive to positive and negative to negative. But I would suggest to hooking up the positives and the trailer positive first then the ground and negatives together last.

[@wakeislander]

Awesome video! Thank you

[@petesrvtv]

Happy to help!

[@Kikinahm]

Good simple info! I kind of already knew and just wanted verification. Though I will undoubtedly use 3 batteries.

[@kimsland999]

I know your comment was 6 years ago Lol. Been living in my single battery (In camper) charged by car and 2 small solar panels on roof. But no matter how charged up this single battery is (Like 13.7volts for hours on end), come nighttime the laptop (alone) drains the battery within say 3 maybe 4 hrs! (Obviously under converter power). Would 2 of these car batteries in the camper work? Or you are saying 3. Omg the price keeps getting higher. Maybe 2? Oh I replied to you because I also knew parallel and all that too. And you came across as confident.

[@rustyshackleford3647]

Excellent presentation!

[@rvscootin3457]

Great Video! The only issue is that from a circuit standpoint. It doesn't matter where you hook up the Negative. Ground is ground, and both the (-) terminals are shorted together. So there is no difference in the draw. That being said... One advantage of this kind of hook up is that the cables reach their respective terminal post better. But there is no difference if you put the Negative on one battery or the other. The current draw will be the same. If anything the minute resistance in the jumper cable would cause a difference in the draw/charge of the main battery, but this is so small that it is negligible. Still I like this setup!

[@kimobrien.]

The problem with doing it 'your way' is the possibility of creating circulating currents. In other words one losing charge quicker than the other on a load like a 12 volt fridge which may be going off and on results in a circulating current after usage for the less used battery to bring up the charge of the other battery. You also want both jumper wires to be as equal as possible in length and mechanical connection. Yes it will work your way but what makes you think there is no difference? Did you actually measure the circulating currents after having a load attached?

[@victorolguin5949]

hey im going to replace my batteries on my 5th wheel... im wondering to remove and install the new ones do I have to disconnect the main power from the pole (50amp connection)???????

[@KE6DOA]

I just bought a 100 W suitcase style and I’m about to go camping in my travel trailer , it has two batteries out on the tongue when I hook up the solar panel do I go to just one battery or do I clip one red to one battery and the black one to the other battery?

[@justanotherpulltab]

Great helped alot

[@petesrvtv]

Glad it helped! :)

[@martinstasiak5622]

@@petesrvtv how would you charge 2 battery’s with one solar panel?

[@ravendy284]

is that the same process when you have solar in your RV? (I have Go solar 160 Watts with 300 watts inverter.)

[@charleslove2319]

Dos this work with deep cyclical battery’s?

[@quintonsedore9684]

If I'm wanting to charge via solar how do I hook up the solar pannel parallel also positive on 1 battery and negative on the other?

[@TANGLEUSA]

Lost me at 2:08. Black wire goes back to one of the reself resetting breakers. ?? So I’ve hooked my battery to the positive… 🤦🏼‍♀️

[@ivanalvarado4872]

Help ! I quickly unhooked my batteries when I took my camper for service cause they said I needed to take them blah blah . Anyway now I have two batteries ..... 3 red cables ( one is for the jack) one black cable and a small black jumper cable. How do I book this up ?

[@harleyjune1233]

very informative thanks - do you have a link to the battery charging products used to charge while driving? alternator to plug - is there an auto shut off when RV battery bank is fully charged? thanks in advance

[@DebbieTomkoSUNSHINE]

How can you tell what guage your wires are? Can you hook up two different size batteries?

[@tman03874]

Hello in the case of many positive cables, both draw and charge. I have solar charger too. do you put them on 1 terminal or is it better to separate and put on both terminals?

[@petesrvtv]

I would put all the positives on one terminal, providing wires were long enough and the terminal stud had enough threads showing to allow the nut to tighten properly. Thanks for watching! Randy

[@bobbygarcia8834]

What gauge did he use?

[@robviolin1]

Good vid, thanks. I have an agm battery. I was wondering how low I can discharge it without causing damage to the battery. When fully charged it reads 12.7 volts. Thanks again

[@RandalMurrayPRV]

Motor loads and electric heat are big draws that I use when discharging or load testing a battery. Thanks for watching!

[@huntertomlin3909]

Most AGM batteries can be fully drained, but the rule of thumb is to go no more than 20% which for a 12 volt agm battery is 10.4 volts. Most dc devices will quit functioning long before this is reached. Remember volts push amps.

[@viralbull8085]

what happens if i connnect 12 volt batteries in series, i didn't know they were supposed to be connectet in parallel. i can't start the rv, don't know if the started battery is just trash but i am connecting a jumper and the rv gives no signs of life

[@RealFloridaHorseman]

What's up with mixing AC and DC wire color codes? The camper is wired black(hot)/white(neutral) like an AC circuit while your DC battery cables are correctly red(pos) & black (gnd). It would be extremely possible to mistakenly reverse polarity to the black (hot) camper circuit with the black (gnd) battery cable. Shouldn't that entire DC circuit be nothing but red/black, camper included?

[@RandalMurrayPRV]

RealFloridaHorseman Welcome to my world my friend! There is no color code for 12volt in the RV world, it's like the Wild West everybody does what they want. No wiring schematics ether! Rule of thumb when hooking up a battery on a camper is look for the wire that is fused and that will be your positive, or look for the wire screwed to the A frame, that will be your ground. Thanks for watching!

[@Toota95]

All went well until the last step when I attempted to connect the jumper from neg of one to neg of the other. Connector sparked and lit up getting extremely hot...what did I do wrong?

[@RandalMurrayPRV]

If something sparked and got really hot quickly you had s dead short, which means things were not wired properly some how. At that point I usually take everything apart and start over and hope for a different result. You were using 2 12 volt battery's correct? Thanks for watching, I hope you got it!!

[@huntertomlin3909]

You were probably connecting while a device was on, always turn you main battery kill switch off, then attach jumpers and finally connect the positive lead first then the ground lead.

[@williamerwin9852]

Good simple info.

[@nautiquecowboynautiquecowb5317]

Thanks randy did just like you said

[@mjones6115mj]

Randy you mentioned a 4 minutes 7 Seconds about charging the batteries off of the vehicle if you have the appropriate setup. But you can charge the batteries from a generator using the 30 amp cord that's supplied with the trailer that's connected to the converter correct?

[@kimobrien.]

Why would you think otherwise? The converters usually use chop the AC so it may result in noisy or singing alternator.

[@mr.chisels729]

Great video, Thanks Randy!! Can I hook up three batteries in the same manner?

[@danaharlan12]

Yes! and even more but in PARALLEL. AS SHOWN.

[@jangles55]

I have 2 6v GC batteries wired in series to make 12v with a 100w solar panel in my E150 van. When the sun goes down I would like to run wires from my starter battery to my 2 house batteries, can I just run the 2 wires off the starter battery directly to the 2 6v battery terminals where the charge controller attaches to the batteries and put a manual inline on/off switch? Someone said because my house batteries are 2 6V in series instead of 2 12 rv/marine batteries I could damage the house batteries. Is that so? Thanks Love your informative vids!

[@kimobrien.]

You only want to charge your two six volts in series when the vehicle is running otherwise you risk losing all battery power. I put a heavy duty golf cart solenoid in the positive line from the fused positive bus at the battery and connected the ground at the alternator. The solenoid is only energized when the ignition is on preventing accidental truck battery discharge. I use number six cables going back to a heavy duty anderson type connectors to change my trailer batteries and to provide power to my fridge on the road. The trailer side uses soft number six welders cable so it bends easily without possible breakage. I once worked for Sun Automotive and I can tell you that all kinds of different batteries made by different and the same manufacturers give different results to automatic battery chargers and testers. You highest voltage is always going to be at the alternator. So to make up for the long wire run to your battery you may wish to attach cables as close as possible to the alternator. My new 2016 Chevy seems to be automatically be shutting down the alternator at times but apparently it is supposed t do that.

[@immeohmyoh]

will two fully charged up deepcycle rv batteries open the slides? or do you need 220v off a generator or 30amp off a camp-post to do that? thanks

[@richardlee4430]

I have a battery disconnect, do I need a different type of switch if I add a second battery?

[@RandalMurrayPRV]

You current battery disconnect will be just fine, with the extra battery you are not changing anything just giving yourself more stored power. Great question! Thanks for watching!!

[@elpollolocoguero8183]

Can I use diesel truck batteries?

[@KeepTheBalance]

what diameter does the ground wire from battery to chassis need to be?

[@judymarie01]

I have one 12 volt battery. I have two red wires and one black.. do I leave one detached.. so confused

[@PilotJ30]

What gauge wire did you use in this video? Thanks

[@RandalMurrayPRV]

Hello, I was using 6 gauge wire in this video, which was the same size wire that came equipped on the camper for the single battery set up. Thanks for watching!!

[@jzh6821]

Is it a problem if i use 8 gauge wire through the whole set up? Thanks

[@charlielough1855]

is this the same as marine and would it provide more cranking amperage

[@rickwilliam3632]

I heard some churping noises in the motorhome earlier today. When I went back in the motorhome a couple hours later to check it out I found that there is no 12 volt power at all, no lights, ect. There is no reading of house battery volts at the all in one panel and there is no power to start the generator. I checked all that I knew how to check, what do you recommend?

[@RandalMurrayPRV]

Hello, If you have a good chassis battery, and a AUX battery switch on the dash, you should be able to get the gen set running. This switch which most motorhome sate equipped with will link both sets of battery's together. A charger on the coach battery's can also be used. Good luck, thanks for watching!

[@ediwaldosanchez7268]

My truck has two Optima gel batteries in it when the 7 pin connector is connected to my fifth wheel it will blow the 30 amp fuse that is inline on the 7 pin connector to the trailer do I simply need a bigger fuse or is my truck having two batteries that are gel the problem because I was under the impression that it didn't matter as long as they were in parallel so that's what makes me assume that I just need a bigger fuse as the fuse doesn't seem stock it looks like to me that fuse was added as a second level of protection any type of help would be greatly appreciated

[@danaharlan12]

don’t add a Higher amp fuse EVER until you have a professional find your problem.

[@jaymonroe9105]

I bought a newer trailer and swapped out the old batteries. I want to wire them in parallel as I have in my older trailer. But, this trailer has a blue wire (with inline fuse) a red wire (with an inline fuse) and a white (ground wire hooked to the frame). I believe the red goes to the positive terminal, and the white goes to the negative terminal on the other battery. Where does the blue wire go, positive or negative and which battery? Hope that makes sense. Thanks

[@kimobrien.]

Blue is usually used for the electric brakes it may be connected to the safety emergency trailer brake connection but you are going to have to either check the owner manual or trace out the wiring itself.

[@buttonbeeandme7601]

Hello Pete's RV is it a must to have the black parallel cable? I was told I only needed the red to connect the two batteries in parallel. Hope someone can answer this question

[@kimobrien.]

Cable color is for quick ID only. It means nothing to the electrons in the copper wire. if ever in doubt use a meter or follow a wire to confirm DC polarity or if the AC wire is hot. You need two cables to connect two batteries in parallel you need only one to connect them in series. if you want twelve volts from two twelve volt batteries connect them in parallel. If you want twelve volts from to six volt batteries connect them in series. If you want 24 volts from two twelve volt batteries connect them in series.

[@treslongwell1332]

Salvage job on 89 Fleetwood Chevy. I just want to get it started to move it a few yards. Can I use just one 12 volt battery? Too many cables.

[@RandalMurrayPRV]

If using my method, hook alternator to the battery not grounded, this way both battery's will take the same charge, at the same rate. Thanks for watching

[@rvscootin3457]

Both batteries are grounded... Unless you unhook one of the terminals.

[@kimobrien.]

I think he means to say is wire to the battery not closest to the grounding cable. in other words the battery with only the ground jumper cable.

[@alonacabiao2620]

How would I hook a parallel pair of generators to that pair of batteries?

[@kimobrien.]

Hook the positive of the first 12 volt generator to the positive terminal of the first battery and the negative to the negative of the second battery. Take the second generator and hook positive to the positive terminal of the second battery and the negative to the first battery. This way the charging rates should be equalized and one alternator should not end up doing more work than the other. If your using different kinds of alternators or longer alternator cables on one alternator than the other or trying to get 120 volts out of either or both generators at the same time I would only use one alternator on the 12 volt side with connections to the positive of one battery and the negative of the other battery. i would also not use battery clips which can easily fall off. Sparks near charging batteries is never a good thing.

[@bobwoerner8731]

quick question,i just bough 2 T105RE 6 volt trojan golf cart batteries, hooked up in series for 12 volt system ,,,,first time i hooked them up to a 1.5 charger /maintainer they reached 13.6 before charge light turned green,,,,,,,a week later i hooked it up again but they reached 14.6 and still no green light,, i disconnected charger in fear of over charge,,,,,,,,,should i have allowed the charging process to continue to green light appeared ?........were the batteries attempting to equalize ?

[@RandalMurrayPRV]

Hey there Bob, Most of the time I see that kind of voltage being thrown at a battery is the charger trying to excite the battery at the start of the charge process, not to finish. I wouldn't be concerned, but I would keep an eye on them when charging. Thanks for watching!!!

[@mikejunk4285]

What if both batteries aren't purchased at the same time? Does it matter that much? I just purchased a new TT 4 months ago and it came with 1 new battery. So the battery is good yet. I just want to add a 2nd battery.

[@dwightstewart7181]

A difference of only a few months, while perhaps not ideal, isn't going to matter all that much.

[@firemarshal17]

How much difference is there between 2 12volt batteries and 4 6 volt batteries? I'm doing a solar system on a travel trailer. Unless I relocate the batteries somewhere, I'm stuck with putting them on the tongue. Thanks.

[@randalmurray3624]

Dennis that would depend on the amp hour ratings of the battery's. if you are not using a large investor to,power something. You can do two 6volts in series on the tongue along with some sun and your solar panel you should be good. Thanks for Watching!

[@danieltucker8146]

I have six batteries which battery is the engine start battery on motorhome

[@stacihamson2532]

What do you recommend to charge the batteries if you're not hauling?

[@RandalMurrayPRV]

Hey there Staci Hamson, I recommend a bench charger to anyone doing any type of camping that will pull their batteries down. The bench charger at home is the best way to start with a fully charged battery, and a great way to maintain your batteries. I have made a video for that recently, winter battery storage. Thanks for watching!

[@glenngeboy3142]

Battery tender. About $50.

[@defaultname2777]

I know you said keep batteries the same age, I have a few questions. My first battery is about 8 months old, I just bough my battery. The current battery charges at 12.7v. I don't know the amp hour. My second battery, I just bought. It too is lead-acid. It's considered deep cycle like first. It has 140 amp-hr rating. What gauge do you recommend. It looks like the first battery is using 4-gauge. Do you recommend 2-gauge. I find this hard to believe but guy at store told me 2-gauge will cause more resistance. I'm having to do this because I cannot run my furnace for more than 2-3 hours on battery. I didn't have this problem early on in the coach. The battery has gotten so low the first time that the low-power alarm went off and I was not able to start generator. I used car alternator to give power to generator. How much should I expect to pay for a good battery. My second battery is normally $129, but I bought it on sale for $95. $50 cheaper does worry me a bit. Do you know typically how long a battery should last on heat. I had no lights on and even if I did they it might have been 1 LED light over the bed. How can I get in touch with you? Thx

[@defaultname2777]

+Default Name One thing I should note. With the first battery, I've seen the voltage will drop from 12.7 to about 12v the instance the heater starts. And good number of times, the blower has been running but no heat. I know there is LP gas because the main panel says so. And I've tested the LP stove and it starts immediately. This last thing has been a puzzle. I'm speculating a short in the blower cause a major power drain. IDK.

[@RandalMurrayPRV]

Wire size is usually determined by the amp draw from the coach and the breaker that you are hooking to. 2 gauge sounds rather large unless you have a large inverter in play. On your basic travel trailer you will typically see 4 or 6 gauge wire. Again locate the breaker that the battery's are hooked to or look at the existing wire to help gauge your new wire. Thanks for watching!!

[@leroymontano315]

Thanks I didn’t have to make an ass out of my self trying to quess at it,

[@petesrvtv]

Happy to help, Leroy!

[@tastyfish4890]

What happens if one batt has 11.85V or 8V and the other 12V are connected in parallel ?

[@RandalMurrayPRV]

Hello, The voltage will most likely equalize or take the lower of the two. You will only be as good as your lesser battery. Always best to start out with two like battery's purchased at the same time. Thanks for watching!

[@tastyfish4890]

Thanks .

[@ravendy284]

what gauge did you use for the parallel?

[@kimobrien.]

Use the same or bigger gage than the output is using. Also make them as mechanically identical as possible.

[@mnsdh21]

if it's 6 Gauge enough but i used 2 gauge it's will be better or Overkill??

[@dwightstewart7181]

With 12v, at that short distance, you're not going to see any difference between 6 or 2 gauge. Of course, that would certainly change with a thinner gauge wire.

[@RandalMurrayPRV]

Hey there mnsdh21, Your wire size is gauged by the fuse protecting that wire, a larger wire will definitely not hurt anything and as mentioned in the other comment a larger wire will give less resistance. Thanks for watching!

[@dogiedaddy3067]

Big problem with this video. He doesn't have the batter boxes fitted in there. I'm trying to do this now and the problem is that I can't fit the batteries and the boxes on the trailer. Don't have a solution yet, but two batteries and the appropriate boxes are not going to fit on that trailer just like on mine

[@dwightstewart7181]

My batteries, each in a group 31 box, will not fit into the supplied space on the RV tongue either. My options are a new metal bracket fitted on top of the tongue, no boxes for the batteries, or some other type of cover over those bare batteries. At this point, I'm favoring the latter option - a vinyl or canvas cover over the batteries. It's been 3 months since your comment. What solution did you finally decide on?

[@RandalMurrayPRV]

Hey there dogie daddy, No boxes were used for a better visual in this video. Your typical travel trailer will accommodate 2 group 24 boxes, which are the batteries in the video, any larger than that and minor alterations will need to be made. I have made two 6 volts work on most A frame set ups as well. Thanks for watching!!

[@YEYEYYouTube]

hey randy, i hooked my batteries up just like you said, but when testing them one reads 12.5 and the other reads -12.5. Is one supposed to read a negative charge?

[@jimhunt4122]

White is ground............ Black or other colors is the POSTIVE. reverse, the Voltmeter Leads.

[@alanmetclaff6718]

You must be ' Randy' every morning!!

[@kentrobinson7479]

2 batteries is not enough unless you also have a generator and/or solar... or just have no room for more than 2 batteries