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Re: Charging Strategy, 1994 RoadTrek, Part 2 (shore power split)
The original distribution panel is still in it, AC and DC, along with a simple converter/charger (MagnaTek). The system is 30amp. So the shore power cable runs to the current distribution panel. My plan was to set up an entirely separate system with the two L16s, a charger and inverter. When I plug in to shore power I would get a y-splitter AC cable and plug one side in to the charger (to charge the L16s) and the other side would be to my shore power cable (which runs everything in the coach). I was just wondering if this would cause any problems, but I don't think it will. The truth is I bought these L16s without realizing all of the additional work I would need to do to support them (with a higher amp charger, bigger cabling to support that amperage, rerouting cabling because they don't fit in the current battery compartment, etc). I'm starting to think I should have just thrown a few solar panels on top instead, but then I've got to figure out how to off-load these two L16s, which don't have a single cycle on them yet.333Views0likes0CommentsRe: Charging Strategy, 1994 RoadTrek, Part 2 (shore power split)
I haven't bought the inverter or the charger yet. Space limitations mean I can't use Magnum, so I was thinking to buy them separately. Thanks for the recommendation on the Progressive Dynamics charger - I was wondering where to start after discarding the combination idea. Yep, that's exactly what I was planning to do - plug the shore power line in to the inverter to make all interior AC hot. And if I actually have shore power, use the Y connector to plug both my charger in as well as my shore power line in. I think that works, just wondering if I'm missing something / not thinking of something.333Views0likes0CommentsCharging Strategy, 1994 RoadTrek, Part 2 (shore power split)
Hi guys, I think I have a handle on what needs to happen with charging. I've been discouraged from buying an AIMS inverter/charger and the other options are either too expensive or won't fit into the limited space I have in the rig. As a result I'm planning on buying the inverter and charger separately. This complicates things slightly because without the combo units I can't just "pass through" AC power to the coach. I thought the solution was complicated, but now I think I can: 1. When I'm hooking up to shore power, put a 30A Y-splitter cable on shore power (in). 2. Plug split 1 into my charger. 3. Plug split 2 into my "shore power" cable. 4. When I'm not connected to shore power and want 120VAC plug my "shore power" cable into my inverter. For some reason I was thinking it might cause problems to "split" shore power, but then I realized it's really not a problem at all as long as "normal" concerns like drawing too many amps doesn't occur (and of course the house is already fused to prevent that). I mean.. right? :) The other option would be to just leave my 120VAC cable in (my shore power cable) plugged into the inverter and let the battery bank power everything at 120V, always. That's a simpler setup, but I'm just not sure if people typically "stack inefficiencies" with a 120VAC (in/charger) -> 12V (batt) -> 120VAC (inverter) conversion.1.7KViews0likes6CommentsRe: Charging Strategy, 1994 RoadTrek
Thanks for the photos. I was unnecessarily concerned about voltage drop across bus bars like that, but it looks like they're in pretty common use and of course really convenient. I also noticed while I was working in my coach that more of the cables are accessible than I thought, so I might be able to do more upgrades than I originally expected. I'm going to ask one more question in the general forum about how to effectively charge my batteries and also have shore power at the same time. I think I can just split the incoming AC and plug one receptacle into the charger, one receptacle into the "shore power" cable and I should be good. Then I can buy my inverter and charger separately (I'm running into space issues with everything but the AIMS.630Views0likes0CommentsRe: Charging Strategy, 1994 RoadTrek
I'll definitely look into replacing the solenoid, this rig only has 70k miles but it does have a lot of years on it. And that's good information to have about the computer regulating voltage. Right, so one power source would be: 400 AH L16s -> inverter -> 120V to coach (when I turn it on) Battery bank charged by plugging in to shore power/genset. The other power source would be: 94AH wet cell -> 12V to coach Single battery charged by alternator and also by plugging in to shore power / inverter pass-through -> converter -> existing stock charging circuit It looks like there is a Magnum Energy 2000W inverter/100A charger that might fit in the space I have available. My reading suggests that's a very trustworthy brand, but also that they've started building in China. I did read some horror stories about AIMS, but I don't know if they're current. Most of the complaints to the BBB have been resolved. Argh.630Views0likes0CommentsRe: Charging Strategy, 1994 RoadTrek
Thanks for the replies, I'm slowly gaining confidence in understanding the trade-offs. 1. I think the alternator on these conversions has been beefed up. That said, I haven't been able to figure out what I've got yet. It's a reman and their sticker covers the original info, so I'll need to peel that off. 2. I probably don't actually need 3000 watts. I was selecting the 3000 because it has a charger at 100A, and these 400AH L16s want C/4 in the first stage. Since I just spent $900 on these AGMs I want to make sure I don't undercharge and sulfate them. 3. That AIMS inverter gets 5 stars on Amazon. Are they known bad? If they are I'll probably go for something else. I'm glad to get this feedback because I was literally about to hit the "buy" button. 4. The whole idea is to boondock for 5-7 days at a time (in one or two locations), then pony up for full hookups at a site and recharge for 12 hours, then do it all over again. I know this is on the edge of the possible, but I'm a pretty lightweight user, and I have propane for most of my stuff if I need it (and a Honda 2000). 5. I'm thinking I'm not currently in a position to get the wiring done to upgrade the circuit coming off the alternator. And I'm not sure what kind of isolator I have at this point, but it's from 94, so it probably is the older type (I can see it, but can't quite make out a model number). I'm planning on doing this upgrade next week, and I think I'm short on experience to do it myself (though I'm getting there, and would prefer to) and short on sufficient funds to pay someone to upgrade everything. Instead what I think I'll do for the interim (until I can upgrade the alternator/isolator and wiring) is just leave the existing 94AH house battery in place with the existing wiring and keep the inverter/charger solely connected to the 400AH bank in back. Then I can just run off the original coach battery for your basic overnights and switch to the inverter/400AH bank when I'm in one spot for several days (or need to run bigger items). Does that sound like a reasonable solution/compromise? I know I'm giving up charging off the alternator on my big bank for the time being but it's pretty clear that this would require more extensive upgrades than I can do right now.631Views0likes0CommentsRe: Charging Strategy, 1994 RoadTrek
I think I've got this pretty much figured out, but I have a question that is probably pretty straightforward for someone who isn't totally new to this stuff: It looks like the stock alternator on the 1994 RT is 120A. The documentation from the battery manufacturer (Vision, chinese brand) says that initial charge current is also 120A. That's perfect, right? It seems like the right solution is, like you guys said: 1. A charger inverter (thinking AIMS Power PICOGLF30W12V120VR 3000 Watt) and just run everything in the coach from the inverter 2. To run the alternator charge line directly to the battery (and not worry about overcharging because the set point for the voltage won't cause problems, especially after the drop through the isolator) 3. To run MPPT solar directly to the battery as well (since it will turn itself off when it sees the charger charging) should I want this in a future purchase And it seems like I can switch between 120VAC and 12V systems just by turning my inverter on or off (turning it on will start inverting to 120VAC and the existing converter won't hit the batteries directly, turning it off will show no voltage from "shore power" so the batteries will be hit directly). Unless I'm wrong, of course. :)630Views0likes0CommentsRe: Charging Strategy, 1994 RoadTrek
Okay, I think I have some more clarity on this. I was worried about multiple charging systems overcharging the battery (they're AGM and I'd prefer not to die in a fire), but if I get a 100A charger/inverter kit I should be good on getting enough current to the batteries for optimal charging, and if I get an MPPT solar controller it will be smart enough to see a high voltage already being applied to the batteries and turn itself off. I think I could literally connect the MPPT output to the output terminals of the charger and it would all play nicely. Seems like the main thing to worry about is the draw on the alternator, looking into that now.630Views0likes0CommentsRe: Charging Strategy, 1994 RoadTrek
Thanks for the responses, really useful. Time to go do more research to figure this out, especially on the battery monitoring system - I really want the power systems to play nice with each other and to be idiot-proof. I hadn't considered the draw off the alternator as being a lot more substantial with the larger bank and was hoping to avoid rewiring (not something I'm comfortable doing myself). My usage profile is more on the low daily AH usage, boondocking end. Just run a laptop, fantastic fan and some lights, so the idea is to get something like a week at a time, then go hook up somewhere overnight for a full charge. Since you're saying to get a full charge every 7-10 cycles, and I'm hoping to get a week per cycle (and I'm going to do this full time) I think that means I'll need a full charge every two months. That's totally manageable. Kind of perfect, actually. I do think I'll leave the existing MagnaTek in there - I hate to get into it and need to rewire everything. If I just pull the fuse on the charging circuit I can't see how leaving it in would create any problems, right? Going to research shunt based battery monitor systems now. Thanks for the tip(s), both of you.630Views0likes0Comments
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