Good Video, One not so minor point. All fuses should be located as close to the source of power as humanly possible. They literally make terminal fuses that mount directly to the battery terminal for this purpose. Why? The length of cable between the battery and the fuse is unprotected, if your chassis were to wear away insulation and make contact with the frame, your battery would dump all it's energy into the frame potentially causing a fire. If however your fuse were located on the battery terminal, or as close as possible, the same worn insulation condition would simply blow the fuse, which is why you have it there in the first place. Once you adopt this practice you are much safer from a potential fire. I'm sure you are aware but for others reading, the fuse has to be the weakest link in the circuit, 20 amp wire with a 15 amp fuse is good. 20 amp wire with a 30 amp fuse means your wire will melt before the fuse. Sorry to be Preachy but I see both of these safety procedures violated all the time.....
I used a voltage sensive little relay that cost £11 GBP about $14 - it triggers the Renogy - it comes on at 13.2V and goes off at 12.8V. I put a switch in with a little LED indicator so I independantly turn it off
Regarding sizing the charger. You can by temprature sensor to monitor the alternator temperature. When it gets to high, the charger is turned off. The problem with maxing out your alternator is that the cooling fan runs to slow at high RPM combined with that litium charges for a long time in CC mode(bulk), so this overheats the alternator.
One of the cool things I find is if you have an inverter you can run your refrigerator on 120v when you are traveling which is much safer than running it on propane while on the road. With the DC to DC charger you can always be sure your house battery is fully charged when you get to your destination even when traveling at night (or when its dreary weather) when solar is not optimal.
@@jounik8980 If you have one thats great. Mines a 2 way....propane or 120v. If yours is 12v you are still probably using 25a/hour so the DC-DC charger is fantastic to keep your house battery topped off.
For those who want to consider a different way, I installed a second alternator on my F350 and converted a stock 120A alternator to 24v using an external 'Transpo' regulator set to 29.4v. I have 17.5kwh of Nissan Leaf cells in a 7S configuration directly connected to the alternator with 4ga wire. When the battery is low, the alternator can charge at 150A and will quickly overheat and burnout....... so I have placed a thermostat on the excitation power lead to the regulator. When the alternator case reaches 120C, excitation is cut until the alternator cools to 110C. Alternators can safely run as high as 140C. I have temp, voltage and amperage meters in my center console as well as a manual enable/disable switch for charging. As a point of interest my 120A alternator can deliver between 80-85A continuously and remain below 120C. A similar 12v setup is not as ideal with a LiFePO4 and single alternator system because of the lower than ideal charging voltage but it can be useful nonetheless. / '
LOve it. Can you show link to thermostat? Does the excite wire now need 24v or 12? What happens when Leaf battery gets full? Now the excite wire is not doing what it is intended for. Is your enable switch connected to the excite also/ In series with thermo? alternators make 3 phase AC power that is rectified to DC. So you get a DC power that is turning on and off. Unlike a battery that is always on. Do you find you have to charge for 1 hour to get 1/2 hour battery use, at the same amp reading? I have 7s also. This has me very interested.
You can protect any alternator and circuit from over heating by installing an external bridge rectifier. Most factory RV alternators are not best for keeping up with power demands of rv batteries and systems so an extra bridge rectifier will add life to alternator and help it function better.
@@hitmanhite I bought my dual alternator brackets, idlers etc as a take off kit from a wrecking yard that advertised it on ebay ($175). (I'm told) Ford only offered it for the 7/3 from 99-03 and on ambulances. You might want to set up an ebay search for one and see if someone wants to put one up....alternatively, scrounge junkyards for ambulances
Wow. You helped me figure out the best practices with this unit. I love the idea of a power switch for the controller, and the 14.4v settings. I would still use the power signal for run however as it is possible to leave the charge switch on a deplete a starter battery.
I'm assuming the manual switch for the DC DC charger would have a positive supply from the ignition circuit ? Not directly from the start battery. But yeah I really like the idea of the manual switch and being able to switch it while driving . Guess you could put an ammeter on the alternator output too and keep it say to a max of 70% of its rated output , more so if the engine is just ticking over at idle .
Hey Brian, I’ve been following your DYI videos for about a year now, and you’re the go to guy for RV / van conversion and upgrades. Thanks for all of your videos!
Good video . If anyone wants to see a good video on trying to charge a lithium battery directly from your alternator just type in victron alternator test
Brian, if you call the Ford dealership and give them the last 6 (I think it's 6) numbers of your vin they can tell you what size alternator is on your rig.
Hi Bryan, thanks for this video. I'm just starting to switch over to lithium batteries and couldn't understand how to change from the stock solenoid to the dc to dc charger. I found the solenoid so I figured I was on the right track but this video confirmed it for me. Thanks. I've been watching your other videos and am anxious to get started with my solar system. Your work is excellent!
I think your choice of the 20amp version was a good one. Better to not load up the alternator too much if you want it to last. Anyway, thanks for another great video!
Thanks Brian. This has been my concern for switching to Lithium. This makes it clean and simple. And I do prefer to use my solar when I am driving if it is sunny since the more load on the alternator the more gas the engine uses. David
Your solar can work perfectly in unison with the DC-DC charger, reducing the load on your alternator. Unless you have a very small alternator that can't handle a maximum of 20A (in this case), its not necessary to shut it off. I don't think going up a hill makes the alternator work harder. When you have the AC and other accessories on, your power demand is higher. That's when you'd want to shut the DC-DC charger off.
Thank you for this. I appreciate keeping to the side of caution. Last thing I want to do is hurt my bus. If you ever install another system like this, you might want to consider a step-by-step 'for dummies' kind of walk through. I'd happily sit through a two hour clinic to learn how to do it right.
Brian - My 2015 Ford Expedition with a 3.5 Ecoboost and tow package has a 285 amp alternator. I opted for the 60 amp charger but also made use of the LC terminal. With your setup, you could easily run a second wire from the LC terminal to your switch location and swap the switch for a three way where you would have off, 20 amp and 10 amp. The charger is designed to cut the output current in half if it detects current on the LC terminal. For example, if your're driving at night and just need to power your refrigerator you could limit the current to 10 amps. You may also want to limit the current if you're driving in the mountains and want more power from your engine.
Nicely done. And I eventually need to do that, but with solar as primary, I use my PRogressive 60 amp LI charger either from shore power or generator as secondary. I put a switch in to turn the alternator on, but have not used it.
Gidday Brian, i'm a newbie to your channel and love the information you put into your videos, they really are excellent. So i'm new RV'ing life and have in the past had a jeep and a small camping trailer with a Roof Top Tent on it, we really liked to go deep into know where. Anyway? I used the Redarc DC - DC to 20 amp charger setup, as i had a dual Battery system with AGM Chassis Battery and a 100AH LiFEPO house battery to run our chargers, fridge freezer etc... the thing i liked about the Redarc is it setup to always prioritize Solar first before alternator, we had a 100w Solar Panel on the roof of the Jeep and we could plug an additional 100w Panel at camp. So driving down the road it would take that 3-5amps of solar reducing the current draw on the alternator. Now back to Binge watching your videos. Cheers, Wes
Please note in this video above, the first two dip switches determine the charging voltage for the lithium batteries. He has his set to 14.4 for Battle Borns. If you have SOK's they want a 14.6 volt charge. Then set the first dip switch to ON (down) instead of off.
@@michaelgegoski1058 SOK 14.4v charge should be set at off/on/on/on/off. Remember that down is on and up is off on these units. So for SOK its up/down/down/down/up.
@@michaeldoherty2289 That is incorrect for SOK. As per above, SOK specifically calls for 14.6 v charging , NOT 14.4. Therefore the first dip switch should be set to the down position for 14.6v
I think you can easily go to 40A charger , they alternator won't have any problems handling that as long as you don't run it in the same time with your lights on , fan at max , and other accessories. usually those alternators are made to handle 140-200A load
Designed output of alternator depends on RPM and cooling. It will output 90 amps but not under low idle speeds (will burn it up). I would limit draw to 20 amps.
I would love a video about a day in the life of RV with Tito now that you are out there boondocking. What do you do with all your setup. Put everything you have done into perspective.
Thanks for the suggestion Jorge. Our days are pretty ordinary actually. Power is abundant. So we do/use the things we would normally do/use. The only difference is that we use very little water.
Jorge read my mind... I love a vid where you show what your days are like. Do you work remote or are you retired? Don’t mean to pry, but I’m close to making the retirement change and wonder what it would be like.
Thanks Tito for the informative video, you explain things is a real world scenario that will be a natural fit for most people. Thank-you for including any small miffs that did not cause any significant damage to the system (Dip switch setting); these are errors that any user could have easily made, and by including that tidbit you may have saved many users from any long term and lasting damage to the system. Your set-up seems to be logical and a configuration that will make sense to a sizeable portion of DIY electrical system RV'rs. Thank-you for sharing your experiences and taking the time to share it with us newbies to these systems that are quite intimidating and appear very complex when we first see them.
At full charge it will ALWAYS have more than 20 Amps being drawn from the alternator. This is mentioned in the product manual as the DC-DC draws a higher current then what it provides to the aux battery (input amps > output amps). Your alternator draw for the 20 Amp DC-DC charger (Renogy) could be as high as 30 A's . This is why they ask that a 30 A fuse be used on the input side.
Really? That’s interesting and good to know. You say thats in the product manual? Is that the Renogy manual? I’m thinking of doing something similar because where I camp solar is only useable if it’s portable with a long wire so you can move it around and even that doesn’t work a lot of the time. Reason? Dense forest so my travel trailer is in the shade 99% of the time except when driving on the highway which means I might as well use the dc-dc charger. I want to protect my alternator and truck battery as well as protect my lithium batteries.
@@prepperjonpnw6482 20A output is 20A x 14.6V = 292W. Charger efficiency is ~92% so input draw is 292W/.92 = 324W. If you are running a modern truck with variable voltage alternator, the alternator may only put out 12.4-13.0V much of the time. Drawing 324W/12.4V = 26.2A (at most) from the vehicle system. In this case, a 30A fuse is too small. Fuses should be 125%-150% of the max continuous current. 26.2A x 1.25 = 32.75A. 26.2A x 1.5 = 39.2A. Best fit is a 35A but a 40A fuse could also work.
@@prepperjonpnw6482 A 30 A draw on your alternator is not really that big of a deal to be honest. I've had this on my standard toyota 4runner alternator for a year and change and its quite smooth in terms of draw. I know folks who have 30A and even 50A's hooked up to their stock alternators and usually they can handle it. You can also upgrade your truck's alternator and there are quite decent after market options available.
@@WorkingOnExploring When in doubt, consult the product manual for what fuse they recommend and do accordingly. Renogy does have fuse requirements for this and other DC products.
Thanks! Good info. I’m basically doing the same setup on my sailboat, but using the Victron Orion TR 18a unit. I could probably gone with the 30 amp unit, but like you, I didn’t want to damage my alternator (51amp). Basically with this set up you’re charging your LiFePO4 bank from you starter battery while the alternator keeps it charged. Thanks once again.
me too; i didn't want to convert or confuse the lead acid-alternator-solar charging, so the DC/DC converter allows all that to stay As-Is, while the house batts are now LiFePo4. The current limit and ENABLE (D+) switch are great for a boat! great set up
Brian we have basically the same rig mine came with a 225 amp charger. I am pumping 40 amps to my battery bank. They come standard with 129 amp alternators, but offer also a 155 and a 225 amp version
Cover that positive post! 5:40 You might want to have a temp gauge on your alternator, that way you will be forewarned if it is being overworked. Question: if you have a 90 amp alternator, why not have a second b to b 20 amp ready to go? If it is heating up the alternator, shut one off.
Alot of those ford e-series have 110 or 130 amp stock alternators. You were wise to be cautious with the amperage provided, as you would need some heavier cable and proper dedicated ground cables to go higher amps. Most vehicles are not well grounded from the alternator to the chassis for high amp loads. Adding extra ground cables from the engine block to the chasis and sometimes to the battery is always a good move, as well as adding heavier or dedicated power feed off the alternator, such as what high end audio enthusiasts do.
Thanks, I just installed mine and your video was extremely helpful. I also used the wire and switch to turn mine on and off. I love not having to reinvent the wheel. Thanks.
This was really interesting although I have a fifth wheel the principles would remain the same. The nice thing is in my 6.7 I have two alternators. As always thanks for the great information in the clear and concise way you present it. Please be safe as we navigate this difficult time.
The Ford starting alternator is 157 amp, the aux on my 2018 is 220 amps. I ran a 1/0 awg cable to a Anderson plug on the bumper (I can also bring into the bed) 2/0 cable would of been sufficient. Anyhow that allows me to run a Redarc 40amp DC -DC charger for my 4 BB batteries. The Redarc is also my solar controller for my portable panels. Good luck
I've tied the on/off switch into the ignition, that means I can't forget to turn off the charger and drain my starter battery. It will only run when both the ignition and the manual switch are on.
I've been meaning to wire mine switch to the ignition also, but haven't gotten around to it. That's one reason I got a switch with a light in it. So I don't forget.
@@RVwithTito You could wire in a low voltage disconnect to the existing switch. That way it would only run the DC-DC if 1) the switch were on, and 2) the starter side was >13.4v or whatever (ie, running)
I've got a Redarc 12 amp on mine. I didn't discover I could have gotten another brand name a lot cheaper until it was too late. Redarc makes a damn nice dc to dc charger though.
Hello there. Question. I am very confused about the engine connection. Do you connect on BOTH the engine alternator and engine battery then to your lithium bank. Can you not just connect only on the engine battery red to positive black to negative. Thanks
My friend has just 3D printed a duct for the fans so the Renogy can be fitted in the electronics cupboard and vent to the outside - an additional 60mm dia vent at the other side of the cuboard helps keep everything ventilated
Brian, Good Video! I have 2017 E450 V10 (Jayco) chassis, and the stock alternator is 120 amps ( from supplied Ford literature). I have a single 100 ah lithium battery, and it charges from the alternator when the engine is running. In order to control when I want to charge, I wired a switch in the coil circuit of the relay that ties the house and chassis batteries together. I enable charging when I’m driving at highway speeds. It typically charges at 20-ish Amps with the single battery
I just used a Ctek DC to DC charger (D250SA) that also accepts Solar input and prioritises the solar over alternator.......the new model Ctek DC to DC charger also charges Lithium. For increased charge rate you can add later a "Smartpass 120"......
I like how you can switch it on/off. Didn't know Renogy made those units. My question: Why wouldn't a standard dual battery isolator unit (diode isolation) work? I know Eaton and Victron make them. Just not sure if they would be suitable for a lithium house battery banks (with voltage/current limits). Hope all is well with you guys! My lithiums are beasts...the BMS has an BT APP for SOC/voltage/cycling #s. Going lithium is expensive...but, night/day difference.
thank you TITO for this information I have the same type of charger in 21A but delivers 45 A engine running (reinforced alternator), charging for the vehicle battery and 100Ah cabin lithium battery.
a bit late response but you main concern should be low rpm /idle condition leadin to overheating of the alternator. since gasoline engine idle torque is sufficient evene idle rotation provides enough power for the alternator to feed requested current from the lithium power pack. and this amperage can reach to 90 or more amps. since idle rotation is very low the integrated fan blowing cold air to the coils of alternator can not cope with this power transmission and alternator becomes a fire hazard itself. limiting lithium charge maximum current to 20 amps is a good call. other intelligent adan adaptive options need additional components if you require more amps to the lithium pack to charge it in a hurry. thanks for videos series btw, good work !
I recently got the same charger for car camping for use with an AGM battery. Great way to avoid solar for small RVs or car camping. For a small RV you might not even need solar with this charger.
I have a 1977 Honey MH. My house battery is deep cycle lead acid hooked up to the Progressive Dynamics Converter / smart charger. I can isolate from draining the starter battery while camping, yet while driving , I am charging both house and starter battery. I want one small lithium battery for tv, not disrupt the current system, but be able to charge it from the alternator and /or 100 watt solar panel I bought a Westinghouse 2200xi for the roof air I occasionally use. Lp for refrig and stove. Dual Power hot water heater. I am stating all this fyi. I like my TV and want to quietly power it. any feedback appreciated.
Thanks Tito for your great videos I have learned alot about solar and many diy projects in my rv. I truly admire how good your jobs end up very clean and professional looking. I have a question for you or any of your followers about Renogy products I have experience a very negative experience with their customer service and warranty fulfillment in particular, they are just non responsive and non professional I purchased 4 of their flexible panels 1 has gone bad by bubbling on the surface and is no longer producing energy I have also bought a dc to dc charger in the past few days after looking at your video about this dc to dc charger but I am worried of the future and responsiveness from this company, any thoughts or suggestions would greatly be appreciated it.
That's unfortunate. I've only picked up a few Renogy items, this being one of them, and haven't had to deal with their customer service. Fortunately, the DC-DC charger is still working fine after a year an a half or so. There's a lot going on in the Chinese market these days. I wonder if that has anything to do with it.
@@RVwithTito I do wonder as well what happened. I can tell you that it is unfortunate to not be able to rely on good customer service for any product its been 2 weeks and no response from Renogy. I honestly think I will be using Victron or battleborn products for what I've read and seen other people mentioned there customer service is top notch. Thank you for taking the time to respond and please continue to post more of your amazing video content I have learned how to do a lot of diy projects for my Rv , God bless.
I've got 150 amps coming from my truck dual alternators and 1200 watts of solar combined feeding my 1440ah Lifepo4 raw bank in the truck camper. Setup is dual victron buck boost converters 12/24v wired (100a and 50a) wired in parallel. Controlled via victron cyrix li cnt relay hooked into the bmv712. Turns in and off charging based upon bank SoC. The Cyrix seems to take care of any back voltage spike. Don't use more than 60% of your alternator output and make sure you've got temp compensated alternator so it will throttle back current and not burn up.
Very well done sir. My rig charges my two house batteries when on or driving, but I can't charge my solar battery bank as everything is in my trailer. Odd, lol, I know. Good luck Brian.
Just run an extra wire to the trailer. I do that with my setup since I only have a trailer and I just have a second cable along the standard trailer cable that I plug into my jeep which has the charger installed in one of the cubbies below the trunk. That allows me to charge the house battery while driving or when my solar panels don't produce enough power.
My 2019 Ford E450 Four WInds Class C RV has a stock 155 amp alternator. I called FORD and asked. No idea what yours would be but imagine should be pretty close.
I installed a Renogy 60 amp to my 500 amp LiPO. No issues. I drive a 2005 Sprinter van. The new stock alternator output is 185 amps. Not while idling. More than 60 amps while idling. I plan to add 1k solar at some point.
I had an idea that you might use a switch for a heated seat or defroster so it would disconnect when you shut off the ignition and won't turn on until manually engaged. This will prevent forgetting to turn off the switch and possibly draining the battery.
Actually the manual does explain the dip switches reasonably well. Problem is, that manual was probably written by the person who designed the PCB with the switch on it, so it was perfectly clear to him/her how those switches work. I had no problem reading and understanding the description of the switches - but then I used to be someone who designed things like that - I'm actually struggling a lot more with a perfectly consumer friendly description of a setting on an iPhone :-)
I found out I had a 225 amp alternator by “pretending” to need a replacement on the website of a parts store. When you put in your vin number it tells you what alternator is a good replacement, voila!
Currently I am using a Victron Energy Cyrix battery combiner. I measure 18A at the house lithium battery but it does not seem to charge the battery. The state of charge remains constant at 77%. Only my dashcam was connected while testing this. This drew 0.2A. I have now got a Ctek Dual 250SE that I will connect the next few days. My car is no fancy camper but a VW Multivan with a 120A alternator.
Brian, Thanks for great videos especially the complete details. One of the points you might emphasize often is that lithium batteries require a higher voltage, to top them off, than the standard alternator is set up to supply. Thus, one of the key reasons for incorporating the DC to DC convertor.
I've installed a Votronic (think it's a German company) they make a tiny 30amp DC-DC charger. The goal is to charge AGM batteries whilst the chassis has sealed lead acid, and of course not kill the alternator. And it's in parallel with a victron mppt for a 100w solar panel.
So I believe you need to add a fuse AT the solenoid location So if a CRASH or other issue causes a High current to Ground The fuse would break the current. Other wise fire possibly would happen and if there is anything scary in a RV its fire they are completely engulfed in less than a couple minuets. My idea Ka7qqv
FYI, your "20A charger' is really a max 250w output.....the current decreases as battery voltage rises. As your LiFePO4 batteries reach a full charge at 14.4v, output decreases to (250w/14.4v) 17.4A. Also, input amperage can be considerably higher than the assumed 20A output Due to operating efficiency of 90%, at low(er) voltage in your vehicle circuit, it can draw more. Theoretically, it can operate on 8v input but realistically, if your starter battery is a bit down and the charger draws it down further, such as when the key is on but the engine is not started, the charger can draw (250w/12v/.9) 23A.
@@tonyhood450 Not at all. A 20A for your small vehicle and 100Ah of battery is likely correct. (recalling from a year ago),There are a number of currents/voltages and specifications involved. It is complex and I may be muddying the water but I'll take a crack at it; Firstly, POWER OUT = POWER IN x EFFICIENCY, since POWER = AMPS x VOLTS, rearranging the equation; VOLTAGE OUT x AMPERAGE OUT = VOLTAGE IN x AMPERAGE IN x EFFICIENCY If either input variables change, the output variables change and the reverse is true. This is a 'teeter-totter' which is ALWAYS balanced. Because conditions of both the auxiliary battery and automobile change, use these equations to determine the limits (high and low) of operation and make sure you can safely tolerate those. 1) The rating (on the data plate) of the battery charger is actually 250W, although it says '20A' on the label. In this case, '20A' is a marketing number and in this actual case, is rarely true. It CAN be true under specific conditions but it is not that much most of the time. In order for the charger to put out 20A, that happens when the battery is at 250w/20A = 12.5V. According to a chart of voltage vs SOC for LFP batteries, that is when the battery is at about 5% SOC. Whenever the battery voltage (and SOC) is BELOW that, it will still get 20A (or more) but when the battery voltage is above that, it will get less (which is most of the time). 2) This charger appears to be constructed to deliver 'constant power'. That means, the current it delivers to the battery and that it draws from the alternator will change. Looking at a couple points, such as the one we just identified, at 12.5V it charges at 20A. How much does the alternator need to deliver to the charger to do that? a) IF this is an old-style fixed voltage alternator that puts out ~14.0V all the time (usually somewhere between 13.8 and 14.4) operating the charger requires 250w/14V = 17.85A at 100% efficiency. Since it is never 100% efficient, assume it will only be 90% efficient and will therefore require 17.85A/.9 = 19.8A. b) If this is a new style 'variable voltage alternator', it is likely the 'normal' alternator output is not 14V but is 12.4V (a good percentage of the time). At the same 20A output, the input would be 250W/12.4V/.9 = 22.4A. 3) When battery chargers operate, they go through 3 modes. The first mode is a 'constant current' (CC, which in your case is actually 'constant power') and it does this till battery voltage reaches the maximum allowed which for LFP is 14.6V (my mistake saying it was 14.4V previously). When your charger reaches this voltage, it will be charging with 250W/14.6V = 17.1A. Once it reaches 14.6V, it switches into 'constant voltage' ,CV, mode and holds that voltage but the current tapers off as the battery becomes 'saturated'. The charger holds this voltage till the current drops to ~5-10% of maximum (1-2A). At that point, it will stop charging for a time and wait to see if the voltage drops, then come on briefly, bring the voltage back up till it no longer drops ('topping' mode).
@@tonyhood450 Fundamental to this question is a brief explanation of 'smart alternator' control. 1) The car intentionally keeps the starting battery undercharged. 2) The reason it keeps it undercharged it to provide a place for braking energy to be stored and later used from the battery so that the alternator can provide less overall to the system. 3) the most common operating voltage from the alternator is 12.4-13.0V so as not to charge the battery. 4) low system voltage is not enough to make some vehicle devices work well (headlights, electric window defoggers and seat heaters etc.) Only when these devices are on, will the system voltage be raised to 13.2-13.5V to make them operate better but still not charge the starting battery or the auxiliary battery. The reason for this operational control is NOT to benefit you, the owner but to allow the manufacturer to present a better fleet MPG rating to appease CAFE mandates. This will result in less battery life (undercharging lead acid batteries is the primary cause of their death) and less available battery power with key on, engine off. As a 4 cylinder engine, you already have a small starting battery and alternator. You might put a larger battery in the vehicle but it will do little good since the ECU will treat it as it does the current battery. If you want to achieve better performance from your starting battery, putting a solar charger on it would help but it is hard to dramatically change the way Ford wants your car to work without circumventing the smart charging system as a whole (which can be done and literally revert it to a constant voltage alternator but I would not recommend it since its integrated operations will have some negative consequences (turning your battery light on to start with). Having a 'toggle switch to charge the accessory battery' is a good idea but likely not for the reason you expect. Your DC-DC -charger is the ONLY way you will be able to charge an auxiliary battery but you should have an 'ignition' wire that enables it to know when the engine is 'on' allowing it to charge. With such a small engine, it is important that you can manually disable this when your engine is overheating, climbing a hill, in slow traffic, passing another car etc.
I have a Victron 12/12 18 AMP on order for charging up a 200AH Lithium with 500 watt solar setup. I'm using this in a very small toy hauler and like you I didn't want to tax the alternator especially when at idle or slow speeds. Sometimes, less is better and for me that's a hard thing to accept as I would normally say "Super Size it", give me the 60 AMP model. My biggest concern is placement of the DC/DC, not sure if it should be mounted in the trailer or the tow vehicle.
Timely for me. Want to charge my 600 AH Victron lithium batteries off my Cummins M11 alternator while driving. Question is combiner vs DC charger. Combiner can go to 400 amps but DC charger only to 100 amps. Much cheaper to go with the combiner, but since my start batteries are Odyssey AGM battery's not sure if that is a good combination. The victron buck boost is programmable and seems like the best option but is 1K more. Decisions decisions..
Thank you #1 question You took 12 volts from your dc to dc output( lithium) ran that to your on /off switch and back from your switch to your dc to dc D+? #2 question did you fuse the wire going to your switch? Thank you again
I have just installed a 40 amp Renogy DC to DC charger in my 2012 Wiinnebago ERA MH. I have it set to also be able to switch the unit on/off and switch between 20 amp max. output to 40 amp max. output. I'm charging 2 - 100 amp-hr. LiFePO4 batteries connected in parallel. My alternator is a standard alternator which outputs 225 amps on a MB Sprinter chassis. I am also using a Amp-L-Start unit which sends a maintenance charge from the house battery to the chassis battery when the ignition is turned off and the house battery is being charged. I have the Renogy dip switches set to 1 off, 2,3,4 on and 5 off for an output of 14.4 volts. All seems to be functioning okay with the Renogy but the Amp-L-Start doesn't appear to be charging the chassis battery with a maintenance charge when the ignition is off. Do you, or any other readers, have any experience with the Amp-L-Start. Before installing the Renoghy Dc to DC charger the Amp-L-Start functioned as designed. I have contacted LSL Prtoducts but still waiting for a reply. Here is a link to the Amp-L-Start and the Ignition Control Relay Kit which I have also installed. www.lslproducts.net/ALS_Overview_Page.html . Thank you for your very valuable and useful You Tube videos. Much appreciated!
I like that you connected a dc to dc charger to use the alternator to charge your house batteries. I bought one just like yours (I also have a Ford E450) but, I still have a generator and want to be able to my aux button to "jump start" If, I spliced the dc to dc charger into the positive line leading from the switch to my lithium battery bank on the battery side and the B+ from the ignition switch ( via a switch mounted next to my Aux button) to turn it off when not needed. Battery bank 2-170ah Lithium in parallel. I have used a lot of your mod ideas but, I just can't wrap my head around this one.
Thank you so much for sharing your knowledge. I have a 2003 beaver patriot thunder diesel pusher and it is ridiculously complicated wiring. Where do I begin to dissect the power grid? Where would I even install the DC to DC charger? I have no idea where power is coming from to charge the house batteries.
Very helpful vid! I'd like to simply leave the lithium batts connected to the Renogy charger all the time I'm driving, regardless of their state of charge. Would that be a problem? Does the charger need to go to float somehow? Maybe the Renogy does that? Thanks!
Thumbs up. However, since you removed your momentary jump start battery solenoid you can't jump start the motor with house batteries if the starter battery goes dead for some reason, like leaving your lights on, etc. You could have connected the DC to DC charger directly to the starter battery. I'm not sure why you wanted to remove the jump start solenoid.
Yes. I could have done that but didn't want to run another cable. I never need to jump my starter battery anyway so it's no big deal for me. I've got jumper cables.
@@RVwithTito if at some point your vehicle starter battery goes to 0 - is there anything special you have to do or disconnect to do a conventional jump start ?
@@lylestavast7652 Don't think you'd have to do anything special. Just jump start. Actually I keep a battery charger so I'd charge it back up from my house batteries.
Thank you, great tutorial. I'm confused a tad... Is this Renogy DC2DC charger not suppose to stop charging when the correct voltage is reached, depending on the dipswitch settings? Or am I getting this wrong? If I have a 7 hour drive day, and my LiFePo4, batteries are full in 3 hours, will it stop for the last 4 hours?
Thank you! I'm going to add the Vixtron 12/12-30 for my Tacoma /Airstream. I know it's IP43, but do you think it's ok, if I install it in the metal battery box that's outside? It shouldn't experience any direct splashing.
Should be fine. Be sure to Install it vertically with the connections on the bottom and a drip loop in the cable just in case. That's how the sailboat folks do it. Good luck!
Yes. The batteries are great. We did upgrade the DC charger to a Victron model though. The Class C was sold earlier this year, but we now have an older Class A that I put more Battleborn Batteries in. Again...excellent performance.
If you read the manual it explicitly says starter battery fused Line to the input of the the DC to DC charger. Incorrect to directly go from alternator
Hi Brian Like your video. I installed a 40 amp dc-dc charger on a 100amp lithium also. So far so good. As far as amperage and alternator speed you only get the max output rating at the higher speed, but it is dependent on load . Example 1, if all batteries are fully charged you would only have minimal amperage coming from alternator. Example 2 ,if your lithium bank was depleted your alternator will only put out about 25 amps because of the dc-dc charger .
I have a 24v lithium battery solar system. I have a Victron 12v to 24v 20 amp converter. I use a ford Computer relay (30 AMP, same one my van uses) fused off the engine battery. Relay powered by a switch (ign power). I cheated. I have dialed up the output on the converter to 29.6v ( 29.6 is the average voltage of solar panel output) and feed the power into my solar controller. With the panels at 100% power input and the dc to dc input I am still under the rating of the 40 amp renerogy rover solar controller. I am very happy with the performance.
Hello my friend, I installed a 40-amp unit, but I faced a problem, which is that the device emits very high heat, in addition to the fact that it does not give more than 13.6 volts. I tried to measure the amperes, but the reading was fluctuating. I wonder if that is the problem. Please accept my regards.
Thank you; very straight forward. Looks like my Dodge truck has a 160A alternator. Any idea what the maximum recommended DC to DC charger rating might be? Of course more amps means faster recharge of the trailer batteries, but perhaps I should measure typical current draw during regular vehicle charging to see what the headroom might be.
Hi. Great information but I'm perplexed on your choice not to upgrade your Alt to a higher amperage or even add a second dedicated house alternator ( great backup potential for the RV) And as for the manual switch is it on switched circuit ? (key on) Great info I'm glad I bumped into this.
Hopefully I heard you correctly, you tied the charger from the alternator is wired up though a switch which is connected though the ignition, meaning only when your engine is running, you can flip a switch to charge your house batteries from your engines alternator & solar vs just the solar!
Yes, most ford alternators are above 90 amps(I say most not all) but that's not what you can truly pull safely! You have to figure out how much does everything pulls leaving how much is left & go by that! Meaning if you do have said 90 amp alternator & with everything running it pulls 55 amps, you only have 35 amps in reserve which in my opinion, having a 20 amp charger added to that is going to tax that alternator to much but if you see when everything is on & you see only 35-40 amps, that 20 amp charger would be fine, with the fact you claim you're only using it once every so often!
Oh quick note, I have a ford ranger with a 95 amp alternator & with everything, it pulls at most 46.3 amps which sure, a 20 amp charger would be in my opinion ok as long as I don't use it as my main charger! But when it's time to replace that alternator, I will be upgrading it to a factory fitted 220 amp one, meaning the new alternator doesn't need any modifications done to mount said alternator & as long as I do the, "Big 3 wire upgrade" alongside it, I know anything I throw at that new alternator, that alternator will be ok! I plan on having tons of 12 volt accessories that will need all that power like outdoor lights, on-board air & so...
HI Brian, It's my understanding like you said that the Lithium batteries will draw what ever is available, constantly. So If they were connected straight to the alternator they would draw what ever your alternator is capable of putting out. Alternators are not designed to put out that much power constantly. They will over heat and burn out. So your dc to dc charger limits the amount of power that the alternator can charge but more importantly it should turn on and off the charge time to give the alternator time to cool down. Like on for 15 minutes then off for 20. Even at a lower amperage draw it can still over heat the alternator especially at idle.
Thanks for this video. I just installed the same Renogy unit to charge a 200A Ampretime battery. I’m confused by the dip switches and Renogy’s chart. Am I supposed to set them to what the alternator puts out or what I’d like the battery to be charged at? The alternator never shows more than 14.1.
