Motorhome 12 Volt Systems Explained..Accidentally!

all right so on this uh 2003 Dutch star these house batteries are dead see they're over four years old now and my customer wants new ones trying to make this a quick video we can check our voltage real fast so if we look on one battery itself almost half a volt huh not very good the chassis batteries so it's very difficult to do this one-handed at 12.6 there so these are six volt batteries whenever I'm changing out any batteries I always take a picture so I know exactly how they were hooked up even though I've done this thousands of times now even though I have a diagram right here you never know what got added or get got changed now these are six volts but this still is a 12 volt system these are the chassis batteries there's two 12 volts but they're wired in parallel so it's always 12 volt now on the six volts side you have four six volts and they're wired in a series parallel so how I always think of these batteries is your trick you're making two six volts to make one 12 volt and you put those two 12 volts together so there's a positive and negative positive and negative on this two batteries right there you can see the positive and negative right there are connected so this becomes the positive terminal and that becomes the negative terminal for this great big battery now so these two batteries made one big battery it's the same thing back there and then on this side yeah the positive going out to the the house side when just the two positives are hooked up together and that's probably the inverter so that's the series here and this is the parallel between the two see Reed batteries even if you don't know how that works it's always best if you're gonna do batteries take a picture so you not hook them up of course you use series you're doubling the or you're you're adding the voltages together when you're doing parallel you're adding the amperages together that's why they do a series parallel on the 12-volt system like that alright let's go ahead and get this disconnected I already took my picture one thing I did forget to say you have a negative ground so you always want to disconnect the ground first it's not that you're gonna damage anything for the most part other than every single part of this metal chassis here is ground so if we try to hook up do the positive side first and we touch the metal surfaces anywhere we're going to short out the system just like putting this cable to that cable but if you are doing ground and you hit anything metal with your wrench you're not going to show it out because you're already yelling so that's why all you wanna do ground first and always count your cables sometimes they fall back here on these new Mars and you can't see them when you forget them also you can see some corrosion we'll have to take these cables off and clean them up a little bit now I have absolutely no loyalty when it comes to batteries that is to say I don't care what battery you want to put in a motor home I think unless they're lifelines or lithium ions you're only going to get three years out of them best case scenario and no matter what so if you get the more expensive lifetimes yeah you might be getting five to seven years but they usually cost three to four times more than your standard battery so I'm not sure the money actually adds up durability on lithium we haven't really figured that out yet they're still pretty new on the market without a doubt they're the best and I I mean if you can do it do it my biggest thing with batteries is you want to get batteries that aren't some sort of local generic battery because RVs are going all across the country and in the u.s. they're gonna be going into Canada and into Mexico so you want to get a battery that if you need to get the warranty approved or replaced on you don't have to go 2,000 miles back to where you got them and in my shop I just use Napa batteries I think the dirty little secret anyways is there's like only three battery manufacturers in the North America and I think most of them are in Mexico they just laughed different names on them yeah they have different specs and different I guess quality to them my own opinion is I've never seen a Walmart battery lasts more than two years that's the only battery I won't recommend so normally with these six volts you get a nice strap like this and you just put it on the hooks but I guess those little hooks were in the way of the cable so those got cut off so I guess I'm just gonna have to manhandle these out do you resist the urge to lift up by this battery vent right here that'll just pop off and then it'll drop on your toe and then you'll be in a lot more pain and wish you had somebody else doing this service the battery tray a little bit this is gonna get acid on it so there's no real reason to make it pristine if you do paint it yeah you'll feel good about it but it's just gonna peel off this was powder coated and once the acids in there it's kind of in there until you completely scrub this thing down sandblast it and go again so just do a little bit of battery maintenance I'll get some terminal cleaner oh this is is that it's also neutralizer so it works out pretty well all right and then I'll let that sit for a little bit and we'll clean that out and then while we're waiting we'll go serves these battery cables yeah because I'm at the shop I'll just be using my wire wheel brush here [Applause] [Music] all right so we'll get the rest of that going then we'll put some batteries in now for these battery cables that I can't just remove and take the wire brush I'll just get a wire brush on my drill holding the drill with the pair of pliers a cable with a pair of pliers like that and then I'll clean them off wire brush always grabs your fingers this right here just a battery temperature sensor yours might vary you may not even have one this is just for you units with that and a bigger inverter sometimes actually have a terminal so you go straight to the battery it doesn't carry any voltage on that terminal it just senses the battery temperature so you'll see that when we just wedged in between them because normally it's stuck on but it's it's a one time stick and they don't stick on plastic very long anyways let me get those cleaned up and we'll start getting the batteries in so these batters did come with new nuts which is good but the old nuts that were on there they'll fit and I like these nuts a lot better because these are washer headed nuts and they're somewhat serrated as a self blocker they also had crush washers these lock washers I don't ever like putting these on batteries one there's bolt that's on that terminal is just in case tin lead and they can only take so much tension before they actually just break the lead but also that becomes a secondary actually gives you two more surfaces to corrode and keep from good contact with the battery to the term are the cables to the terminal and then of course with the washer head it spreads out the load and holds onto that cable a lot better so I like these a much much better if you have them I'd use those instead just clean them up and use them of course highlight to make sure the actual true leads are hitting the terminal itself and then the jumper you're going to go on top of that cable that's just my opinion on things but of course RVs being what they are they always make my life more difficult than they ever need to be so these batteries are a little bit different design and so that cable won't make it they were there that would have fit it's not to make new cables all right let's go get some parts well when it comes to making cables I just lay them out how I think I'm gonna do it I'm gonna go ahead and strip this back so I can put a ring terminal on I just found my nearly destroyed these are actually Mac I think cable cutters do a good job of scoring the insulation then I slice it with the knife and peel off the insulation just slip in right there we're gonna crimp this thing on I just use my battery cable crimper slide it in right there and hit it with a hammer there we go tripped it on that side with a little dimple and also puts a wedge down below and it crimps it really well you don't have to go crazy with it it'll crimp it that's right so so what's the outfit all right so that's in place right there I'll just bring this over to where I think it needs to be find that up and that looks about right I'll just make a mark right there and right there pet it right there and ship it right about there yeah but that banner keep it worked out perfectly you know on the other side too now I am not convinced that putting heat shrink or electrical tape here there's really that useful yeah it makes it look prettier I won't deny that but it doesn't really protect it from corrosion as much as you think it will neither one of them are completely weatherproof and what happens is moisture does get in there and because it's covered you can't see it and it doesn't dry out so fast I've had battery cables that have been corroded this far up inside the insulation because it just creeps its way in so I'll still put probably loom over the top of this so that it does protect the cables from a little bit of wear but that's about it I make finish this one up make the other cable then we actually put these battery cables back together now if your best to tighten up these before we do the the grounds that way again once you hook those up it'll be hot with that one should be all tightened up check all our connections make sure nothing's loose I do like to early spray it with some terminal cut protector it's a little bit more than red spray paint but helps neutralize the acid a little bit and keeps things from building up also looks I guess a little bit more professional all right let's check the battery voltages not that I would normally check batteries this way so for checking the individual cell here our individual battery six point three okay so we're on positive terminal there negative terminal there for at twelve point five six twelve point six six fully charged these are a little bit discharged I guess but let's go ahead and start the engine and see if we're charging off the engine good news is the steps working it wasn't working before these batteries on good Newmar has a bird system in it a bird is a bi-directional isolator relay delay just an acronym so there's a time delay before the engine that will start charging the house battery that way it's not an instant load on the alternator for both the chassis batteries and the house batteries gives the time to ramp up and if the house batteries are so low that is taking the amperage or current too much turn away from the chassis battery and causing problems it'll shut off that charge so that it doesn't try to charge the house batteries and keeps the charge just for the chassis battery it's important to remember because I'm gonna be doing a different system using a bird pretty soon they're guys bad news we're not charging the house batteries I don't think you can hear me very well but this charge solenoid is bad because that's just how life goes I guess that's the birdhouse telling you about that's the charge relay that should be house battery power there this is chassis batter down below chassis we're definitely this is uh trying to turn that solenoid on I'm just trying to turn it on let's say we've got a bad relay well that's pretty unfortunate so I guess the simple job turned into quite a bit of work just just four batteries how hard is it change out four batteries I guess the next check is make sure that the inverters charging the battery the house batteries because that should always be the thing the birds should be that's the bi-directional part of it it should allow the inverter to charge the chassis batteries but that charge solenoid is not working okay start the generator there we go it'll take a minute for the transfer switch to kick in before the inverter will kick on so it's still waiting for AC hey we're both charging let's see if what we got on the batteries all right so we're getting 14 volts there so that's good that charged side is working the alternator is working it's just the charged solenoid it's not working let's go take a look of course now it just so happens that I have a charged solenoid that I was going to be using on another job so I'll just order another one get this one coming there's a pretty common one the one that's on this rig is a white Rogers this is a Trombetta they're virtually identical these are continuous duty rated so you need to make sure it's continuous duty rated not intermittent this is the only place in an RV where the two sets of batteries actually link up in years past that used to be called battery Isolators they were a big blue looking thin heatsink looking guy but this is a charged solenoid and your auxilary start so I'm a lot of RVs you'll have a battery boost just like that or auxilary start or you can start the motorhome engine with your house batteries in case your engine batteries are dead this is what that's turning on it's linking the house batteries to the chassis batteries as you can imagine especially on Diesel's they pull a couple over a thousand amps on that starter so if your continuingly using you have tiller we start to start your engine you're going to burn the solenoid out but also just given time these burn out because there's just a plunger in here that connects those two port points together with like a copper washer and it starts to get overheated and burnt out though that's my long-winded explanation let's change this out and see if we got charged again that would be power from the battery we hooked up that cable already this guy goes to the charge so even if the battery just connects off it's always charging the batteries in vice versa is coming from the chassis battery and this is going to your bird by a directional isolator relay delay and then the other side of the coil is just going to ground so it's pretty straightforward just four terminals and two screws so let me just get this popped out real fast it's just like that so this is the ground down to the bird and then ground is going over to the disconnect over there's a disconnect system for a ground on that this red is a control wire from the bird that activates the charge solenoid whether the chassis battery charges the change imagine charging the yellow wire right here actually goes to that battery boost switch on the dash so this is what you're still activating off that switch now we can start the engine and see if we're charging alright so if you can hear me get the engine running and look at that we got 14 boats go into the house batteries with the engine running it's a let's fit into the chassis battery let's turn the engine off and let's start the generator again then let's wait for the battery charger to kick on we are both charging again let's see what's going back at the batteries now so now these should be charging because they're hooked up to the battery inverter that looks right so now the engine battery should be charging and they are we did it all right guys well so there you have it it's supposed to be a quick video showing you how to change out some for house batteries turned into battery cables and a battery charge solenoid the bird system like I said we might be revisiting here shortly Newmar used it pretty exclusively some Fleetwood's a lot of thor products Winnebago did not ever really use it so Thor Damon Monaco on some of their coaches they had a bird built into their battery control center in the back and a lot of Fleetwood's have a battery control center with a bird system but not not the intelligent system that this one has but a very similar one works on the same principle so there's a bad solenoid it's a pretty common problem so the big lugs are the battery and the two small ones are the coil that activates the plunger or the solenoid I hope you guys learned something from that if not at least I got it done thanks a lot hey you know what by the way I'm uh I'm really deeply encouraged by the amount of subscribers that keep I guess subscribing to the channel I did not even remotely think that that be possible I'm pushing 1800 now so there's a heartfelt thank you I know this last month I haven't been putting out too many videos it's just been an incredibly stressful busy month for me and I'm doing my best to change things around on my shop I got a lot of things coming around and a lot of different choices to make so again thanks for watching guys this is three yot go get some parts and come back yeah I guess maybe I should have checked the voltage before I sprayed it I do a small ice ladder we were here

Channel: AZ Expert

Views: 32,707

Keywords: 6 volt battery, rv electrical, rv repair, lifeline battery, lithium battery, napa, intellitec, isolator relay, charge relay, dutch star, newmar, battery cable

Id: KQp7NI2cHmY

Length: 21min 22sec (1282 seconds)

Published: Wed Dec 11 2019