I'm looking at running all 12v led lights and radios. A house refrigerator. And the normal AC outlets and roof air conditioners. I'm thinking 6 to 8 golf cart batteries. For now I will use the included 4.5kw gen.
So what are people using for an inverter/charger? I'm looking at like a magnum 3kw inverter with a 125a dc charger and a 60 a switch all in one unit. I'm not looking at boondocking much but want the option. Do you think that is enough? Or should I go to dual 2kw's? I'm on a some what tight budget but I also want to do it right the first time.
Thank you,
Eric
you can pretty much forget air conditioning on batteries...
refrigeration maybe 20 hours....
it takes a very sophisticated inverter to run a microwave.
Running AC loads off a inverter is not difficult.
6 to 8 6v golf cart type batteries will do what you want if they have enough amperage.
A 3000w (not kilowatts) will run one AC and the refrigerator off the engine altenator through the batteries if the
engine is at road rpm and the altenator is large enough. You simply have to be able to put equal or more amps in than you are taking out of the batteries.
If you try to run an AC off the inverter while parked, it will kill the batteries in minutes.
I have a Vanner 3600w true sine wave inverter, It runs off of 6 6v Surette Rolls Royce batteries. These are very expensive high AH batteries. I also have a bench tested 300 amp altenator that I can couple to the batteries with the flick of a switch. That allows me to operate one roof air and all other AC loads (I also have a household refrigerator/freezer) while cruising.
I recommend if you have an auto defrost freezer as we do, install a switch so that when "boon docking" you can switch the auto defrost function off. Simply turn it on when you are charging the batteries, however you do that
(I consider boon docking to be at a rally with no external power. If I really wanted to do that, I'd sell the coach and go back to a tent)
My inverter runs the microwave/convection fine. If we are going to use them for some time, we run the generator. Heating things up is no problem. We do not make coffee often with only the inverter. It works but anything that creates heat sucks a lot of amps.
My block heater is not connected to the inverter bus. I need shore or generator power for it.
I have done it this way for over 18 years.
Others will differ, but I believe if you put all your eggs in one basket, one rotten one will ruin the lot. My inverter is a inverter only. I also have two 100 amp chargers with a sensor between them. If the demands are less than one charger will supply, it runs alone. If the demand exceeds the capabilities of one charger, the other will automatically join in.
My feelings are, if everything depends on the inverter and the inverter fails, you no longer can charge your batteries either.
I am not an electrician! I only know everything electrical is manufactured with a certain amount of smoke in it.
If it stops working, get it fixed.
If you try to fix it and let the smoke out, you need a new one.
There are a lot of smart guys. Some of them are on this board. If you are like me and are a bit dimwitted when it comes to electrical, let them educate you. Or do as I did and pay through the nose to hire an expert. The first step is to figure out what your power requirements will be and design to that specification.
It's late tonight so I hope I have helped.
Welcome to this madness.
Joe, how about a ball park $$ amount.... ;D
I was thinking from the point of view...
I'm thinking 6 to 8 golf cart batteries... and ... I'm on a some what tight budget ....
Don,
As the old saying goes...."If you want to dance, you have to pay the fiddler".
You'd have to price the inverter online. Mine is a Vanner, I've had it 18 years and I think they are out of business.
L-16 type 6volt golf cart batteries start a little over $100 at Sam's. The more AH you need, the more they will cost.
If you cheap out and get the low amp hour batteries you will not be happy. BTDT!
I have had two sets of 8 8D 12volt batteries = 1 year each.
6 6volt L-16 auxillary power unit batteries = 6 years + and were still OK.
I now have 6 Surette 6volt batteries (same size as L-16s) = 10 + years and show no signs of weakening. They were guaranteed 8 years in RV application. I got a pretty good deal on them from a distrubuter in Phoenix. I had a Alaska Dealers license so avoided sales tax also. Seems they are 595AH each. So 3570AH for the set. You'd need a whole bay of batteries to equal that!
I would check the distrubuters in the larger towns for them. If they get a year or so old they may be discounted.
The off grid folks have never discounted them and they are more expensive.
I check the water every couple of years and seems I added a little once. Most folks would say I use them hard.
These longer replies this late at night seem to have a lot of mistakes in them I keep correcting.
Hope this helps. If you want, we'll discuss it on the phone sometime. I sometimes have a harder job explaining things on the computer.
If you can run a 24 system to power the inverter, current loads and cable requirements fall in half. but it depends on what voltage your bus is - many GM's are 12V. The Magnum 3012 (and the newer 3012 Hybrid) is an excellent inverter and charger, it's the 12V version of my Magnum 4024. You can't go wrong with it, but get the remote control. Adds a lot to the control of the unit. Call it $2k for that inverter, set up and installed, more for the H version. I have four US Battery 232AH 6V batteries, $100 each-ish, and obviously the more the merrier. I over-night with no power often, my microwave is just fine on the Magnum. My actual prime use for the whole setup is running the roof-top AC while driving.
Brian
Hi Eric,
I feel qualified to comment on this because I've pretty much just been through all of this. What I'd recommend as a first step is arriving at your best guess of your electrical requirements, and how you're going to use your coach before getting too far down the road of figuring out equipment you need. Talking about components before you know these things is a little like leaving on a trip and not knowing your destination. Yeah, it can be done that way, but probably not as efficiently - or cheaply.
Sit down with your travel partners and figure out what a regular day would look like as far as energy consumption. How many hours a day will the fridge run? How much power does the average fridge use? How long does it have to run on batteries? Do that for every item, and you'll come up with a number of watts or amp/hours you need in a day. Use this number to plan your system. Cruising sailboats do the same thing, and there are websites that will help you calculate these things. If you're like me, you might find that your electrical requirements are less than you were thinking. It might also lead your thinking in directions you hadn't anticipated.
The other thing is figuring out alternative ways to run things. For example, to run your roof air units from batteries can be done, but to do it for long periods (8 hours for example) is going to get expensive. Perhaps you decide that if the A/C is needed, you'll just run the generator. These are all individual decisions, but there are a lot of ways to "skin a cat," so to speak. In your planning, you may find that you're trying to solve imaginary problems that don't (or won't) exist. I'm just suggesting that it might be worth sitting down and doing a little "best guess" planning before starting to chase your tail about what inverter to get. If I've done anything wrong in my conversion, it's that I've spent too much money solving problems that existed only in my head before I knew the actual situation.
Hope this helps.
EDIT: FYI, my setup is the same as Brian's (above).
Surette truly the Rolls Royce of batteries did you buy those from Copper State Battery in Phoenix Joe sometime they are affordable there when they want to move some stock around
Fwiw mine lasted 15 years I gave them to guy that sent them back to factory for a rebuild and he is still using the Surette if I knew you could have those rebuilt I would have kept them ???
The Surrette factory is a few miles from me here in Nova Scotia.
Brian
Thank you all very much for all the great information. I'm quite busy so please don't ever take my lack of response as rudeness. I guess I need to sit down and figure things out. I don't even have the bus in my possession yet but it is ours! :) We will be traveling with 6 out of our 8 kids and of course my wife and I. We plan on a full size house fridge along with only roof a/c's for cooling, and using one of those while we drive when it's hot enough for it. Microwave might get used without shore power but I don't think much. We are planning most of our time hooked up at a campground but want the option of boon docking from time to time. I like to plan be able to do just about anything at anytime. I will have a 4.5kw genset but I don't want to have to keep transporting gas for it. I'm not sure if I'll convert it to propane or not to just reduce one fuel type on the bus. The gen set doesn't have a tank yet either so I'll have to figure that out, hence another reason to consider going LPG. I'm just trying to learn about the things I don't know about so when the time comes to work on it I can get after it! We are looking at doing quite a quick build on this unit.
Thanks again,
Eric
Quote from: daddyoften on October 10, 2014, 06:10:54 AM
Thank you all very much for all the great information. I'm quite busy so please don't ever take my lack of response as rudeness. I guess I need to sit down and figure things out. I don't even have the bus in my possession yet but it is ours! :) We will be traveling with 6 out of our 8 kids and of course my wife and I. We plan on a full size house fridge along with only roof a/c's for cooling, and using one of those while we drive when it's hot enough for it. Microwave might get used without shore power but I don't think much. We are planning most of our time hooked up at a campground but want the option of boon docking from time to time. I like to plan be able to do just about anything at anytime. I will have a 4.5kw genset but I don't want to have to keep transporting gas for it. I'm not sure if I'll convert it to propane or not to just reduce one fuel type on the bus. The gen set doesn't have a tank yet either so I'll have to figure that out, hence another reason to consider going LPG. I'm just trying to learn about the things I don't know about so when the time comes to work on it I can get after it! We are looking at doing quite a quick build on this unit.
Thanks again, Eric
We were all starting at one time. A couple of things - if you haven't already bought the genset, think of diesel. It's practical to run on the same fuel as your engine, you can put in a separate tank or pull from the main tank, etc. And diesel generators are usually quieter (a BIG consideration with gennies). PS - some people have tried the "air cooled - construction type" genset sold on the shelf at Home Depot in RV's -- usually with very bad results. It's very difficult to get enough cooling air, they don't stand up to over-the-road engine/road vibration well, and they're devilishly loud. No matter what you pick, look at the Park noise rating - and you'll almost certainly have to have a water-cooled unit to get one quiet enough to not drive yourself, your family, and your parking neighbors totally nuts!
Also, I don't have roof units but many people I've talked to say that one roof A/C isn't enough under most conditions from "warmish" to hotter. I know a couple of people who say that for 3 people traveling down the road at temps mid-80's or above, you really need about three. Considering they'd probably have a driver and passenger up front with the big heat transfer of the windshield, the other passenger more in the middle of the bus ("living room"), and the engine under the bedroom, even three is marginal. Add "American Western desert temps" and you need even more. Plus, you're looking at 8 people - that a lot more heat and water vapor/humidity loading right there than most of us would experience. Lowering the humidity is a very important part of air conditioning, too, so that should be factored in. So, think hard about the number of A/C units you'll need - in practice.
Finally, A/C units (and refrigerators) pull a lot more current when they're starting up than just running. Some people say that if you think you'll need 4kw (4000 watts) to run your A/C's and fridge, then you should budget at least 30-35% more wattage (i.e. about 5200 - 5500 "peak watts") for your power supply. With a 50 amp, two leg (240 - 120V) shore power supply that's no problem but it makes a lot of difference in generator size.
An older Koehler 4.5kw twin cylinder gas gen set comes with the bus, It's a regular rv gen hence why it doesn't have a fuel tank. Great information. Our floor plan is going to be a bit different than most, I might run 3 a/c's. I keep hearing that 2 isn't enough so I need to think about that one. We are thinking about a side isle with a 5+ ft bedroom, a 6 ft bunk room, 5-6 ish ft bath and then the rest to kitchen and living room, so our living and seating area will be smaller than most and there will be a door at the beginning of the hallway. And yes I know a side isle in a 4107 will be a squeeze.
Quote from: daddyoften on October 10, 2014, 10:10:42 AMAn older Koehler 4.5kw twin cylinder gas gen set comes with the bus, It's a regular rv gen hence why it doesn't have a fuel tank. Great information. Our floor plan is going to be a bit different than most, I might run 3 a/c's. I keep hearing that 2 isn't enough so I need to think about that one. We are thinking about a side isle with a 5+ ft bedroom, a 6 ft bunk room, 5-6 ish ft bath and then the rest to kitchen and living room, so our living and seating area will be smaller than most and there will be a door at the beginning of the hallway. And yes I know a side isle in a 4107 will be a squeeze.
A center aisle is good because if you shut the door forward and aft of it, it's part of the room. Not so a side aisle, but with 8 people in the bus, it might be the best solution for your needs (accessibility for some people while quiet/privacy for others).
I'd suggest you think about the bathroom sink outside the bathroom. If it's inside, is one person is shaving/ putting on makeup/ bruching teeth and another person wants to use the potty, you have a crowd. If the sink is in a corner outside, it doesn't "control" the bathroom. It is a tip I got from a long-time S&S owner and I like it (although I usually have 6-7 fewer people in my bus than you will).
Good idea on the outside sink, that's a thought. Another reason for the side isle is making enough headroom for the fridge and stackable w/d, which can only sit in the middle roof line
Quote from: daddyoften on October 10, 2014, 02:07:33 PMGood idea on the outside sink, that's a thought. Another reason for the side isle is making enough headroom for the fridge and stackable w/d, which can only sit in the middle roof line
Have you thought about a roof raise? It is a big investment in time (and in $$$ somewhat) but if you're trying to put 10 gallons in a 5 gallon bottle, it will go a long way towards giving you a lot more useful room. I think that with your plans for so many people on board, you'd need it even if you found a place for the appliances elsewhere. And yes, a w/d on board is a very good thing.
And be creative. My bus has no "bays" for storage underneath so I've had to put things in in other places. For instance, my fridge is sunk 8" below floor level; that gave me lots of issues with cutting out the floor area, framing it in, getting fridge air circulation right, etc. but it allows me to put it where I want it.
Somebody once told me that one hour of planning, looking at things other people have done, working out your needs in detail etc. is worth 15 hours of building. I think it's worth even more than that. They laugh at me for going back and re-doing things and moving things around but I feel that the effort is worth it -- I only wish that I'd planned better in the first place.
Good luck, BH NC USA
Clifford,
I bought them in Phoenix. I can't remember what I had for lunch. I'll look it up in the receipts and get you an answer later.
I did not know they could be rebuilt. Good to know!
Eric,
You've gotten a lot to think about.
I don't understand a 5' bedroom. A queen is 60" (5") wide and 72" to 80" long.
Hopefully 6 of the 8 folks are of diminishing size. That sounds challenging. Would fold down bunks work?
As others have said, depending on insulation, and choice of areas, It will get hot. If you plan on 3 or 4 ACs, you need a 10K generator or larger.
When we're travelling, I can cool ours fine with the front air. I just close the pocket door behind the kitchen. I run that air off the inverter. I have a driver air setup but haven't needed it enough times to get me to install it. The few times I have had dyslexia and found myself in the desert southwest other than in the winter, I have had to run both airs. Even then it was marginal and the generators heat up if you drive over 55mph due to the low pressure areas.
DO NOT GO TO THE SW IN SUMMER! The last time I was at Cliffords, it was 122 when we left Yuma and after my truck sat for a few hours, it was 138 in the truck! I was in a pickup though. Doyle stayed in the AC in his bus in Cliffords shop.
My generator is 18 years old, including 8 years of full timing and doesn't have but a few hundred hours on it. Those hours were put on a hundred or so at a time when we were parked somewhere.
In my opinion, a side aisle creates a lot of space that could be used for making other rooms more roomy. Now if that side aisle could accommodate 6 fold down bunks.......
Debo gave you some great recommendations.
I think I would gather up some large cardboard boxes and mock up my ideas to see how they fit.
I have seen coaches with sleeping setups in the bays for kids. They were entered and exited through cut-outs in the floor. 12v fans and windows with screens. Inside bay door latches too. The ones I have seen though, the people said the bays were unoccupied when travelling. I wouldn't let kids in there either. I have seen commercial buses with driver sleeping quarters in the front bay that one driver slept in while the other drove. These were entered from inside the bus also.
I believe you are limited by your imagination, (and resources), There are a lot of folks here to help.
Analyze their input, think it through, and "Git er Done"
I would have at least 4K of inverter to run two AC's on the road, an 8KW generator to run four AC's parked, and I would tow a 20' travel trailer.
Brian
I reread your post.. Have you considered just buying fuel for gen set? Do the math and see how much fuel you can buy for cost of battery bank and inverters. 4000 watt pure sine wave--2500$ Battery bank 6ea at 250= 1500$ total around 4000$ plus you will need to replace batt--say 5 yrs. 4000 divided by 4$ gal fuel= aprox 1000 hrs running time. Also most roof tops require 15 amps to start each=1900 watts for each. Also most inverters are rated as surge and not continuous. Example a 4000 watt might only have a 3600w continuous operating ability not enough to start 2 ac at same time and would be marginal to keep running without any thing running. A refrigerator will keep ice cream fairly hard for 6-8 hrs disconnected with door shut. Mine does. If you have LP refrig then no problem. just a observation to think about. Bob Ps deteriorate with age whether used or not
Yeah, once we get it home, get time to work on it and then remove all the parts and pieces included with it we can have a clean flat floor to play with, lay down tape, put up sheets/tarps and cardboard. :)
The reason for the side isle and 5' bed room is as follows; if we went with a middle isle and placed the bed long ways like most then the bedroom would be at least 7'. This would give us 6" or so at the foot of the bed and standing room on the side of the bed but we would loose about 2' of linear room. Plus the bunks wouldn't have any privacy and the floor would have to be kept clean all the time. The bunks would still use 6' of linear space. Then we wouldn't have the tallest roof space for the stack-able or fridge. With a side isle we can set the bed sideways and only use 5', have standing room (limited head space) at the foot of the bed and just crawl into it. The rear of this bus has a fiberglass cap over the engine which we can use for cabinets. We can also have a separate door for the bunk room and the floor can be a mess if need be. This will also let us use the tallest roof line for the stack-able w/d and fridge.
Roof raise; The PO gave us volumes of bus conversion magazine's from the early 90's. These are pretty cool to look through. They were doing roof raises back then on ANY bus. But with the stressed-skin construction that the 4107 uses this can cause problems. I have done research and I'm not going to go there with this structure. We are looking at only using this bus for a few years so we can look at a better coach later and look at a raised roof for that one.
Pulling a TT; See above about the stressed-skin construction ;) They aren't structurally sound for heavy tongue weight and can rip the engine compartment off.
The basement sleeping arrangements sounds interesting but doesn't sound very safe for little kids, the one's we are taking with us range from 3yrs to 13yrs old. Plus with that many little one's we need as much storage space as we can afford. I'm even trying to figure out what to put in the wasted space from raising the floor level up front and the spare tire compartment. 8)
Back on topic..... ;D All the "good" inverters I'm finding all include the charger and switch. I like the idea of the all built in one unit but also can understand the if one breaks you're screwed problem. I've learned not to do the built in DVD player in the TV thing. I will need to sit down with the DW and discuss our travel intentions and situations along with energy use to figure out how to power it all. I'm definitely leaning towards 3 a/c's and working real hard on insulating the "house" as much as I can. Maybe even doubling up the ceiling depth where I can to double up the R value. The floor is ok but I think I'll take it up and insulate there where I can as well.
Eric
"Pulling a TT; See above about the stressed-skin construction Wink They aren't structurally sound for heavy tongue weight and can rip the engine compartment off.""
Most GM's can handle a 5K lb trailer without too much problem, with an appropriate hitch. I did think about that before the suggestion. The undercurrent is that 8 people full time, or even longish trips, in a bus is a fate I would not wish on anyone but my worst enemy. Two weeks is about as long as I could imagine... Weekend camping trips would be pretty cool, though.
Brian
Quote from: bevans6 on October 11, 2014, 06:10:38 PM
The undercurrent is that 8 people full time, or even longish trips, in a bus is a fate I would not wish on anyone but my worst enemy.
Brian
I take it you have no desire to be a rock star ... ;D
I have read not to load the rear hitch past anywhere from 300-600 lbs. Hmm, I'll take more input though, but that point only matters for me in the idea of hauling a light motorcycle on the hitch sideways. Otherwise we are already flat towing a medium wheelbase high roof sprinter. But I would like to know more about towing capacity for a trailer as we might from time to time tow a cargo trailer if it will do it safely.
As far as enough room for all of us... we are a closer family, we home school and, as odd as it sounds, we actually like spending time together, ;-) lol. We are planning of only using the bus for essentials and spending most of our time outside.
And as far as a rock band.... I'm just retiring from a local rock band and I'm selling my complete drum set gig ;-)
you might consider a tow dolly equipt with a motorcycle platform.
ps. i have found based on cost to modify and fuel, that it is more cost effective to drive the toad behind the bus, my wife does that for us.
i do haul a 14 foot trailer often also behind our Eagle.
Quote from: daddyoften on October 11, 2014, 07:11:50 PMI have read not to load the rear hitch past anywhere from 300-600 lbs. ...
My bus has a frame (so it's no fight I got a dog in) but I think that's "tongue weight" -- the actual downward force on the hitch. The weight you can pull is much higher. But I think that you're wise to be wary so consider all the factors and get advice from someone who has worked this out.
A bit off original topic but was brought up about side versus center hall. My mind says that a side hall or a split bath in center as a lot have, have the same usable space if the doors in the hall are of the same size.
I have also used boxes and 1x3 scrape wood to frame in walls and kitchen .I did the tape on floor first.I have gotten to a 28 " hall.
Also interested in tongue weight for a hitch on a 91 102a3 .I was thinking of loading a 2 motorcycle platform .2 500lb bikes. Or worst case one front and one rear .
Seems to me that 2 500 lb motorcycles on a platform would be the same as a 1000 lb tongue weight. A small trailer with the bikes on it could have a tongue weight of only 100-150 lbs and be much more acceptable. Don
Quote from: solodon on October 14, 2014, 04:52:28 PMSeems to me that 2 500 lb motorcycles on a platform would be the same as a 1000 lb tongue weight. A small trailer with the bikes on it could have a tongue weight of only 100-150 lbs and be much more acceptable. Don
Yes, exactly. Some people don't like trailers ("touchy"- you have to keep checking on them all the time; you have to disconnect to back up; how will you pull a toad; items aren't secure from weather and theft/vandalism, etc. -- and these are all valid concerns), but you're absolutely right about this.
Bikes on a rack have the load cantilevered out from the frame, so you need to also calculate the torsional load. It is in no way similar to a dead weight on a hitch ball. Also, a rack strong enough to hold 1,000 lbs of bikes is going to weigh 500lbs or so anyway. Just advising to get your slipstick out and do some engineering on this.
Brian
I realize carrying bikes would be heavy but easy for getting to track days and makes unit a lot shorter than with a trailer. We do have a small trailer that can carry bikes. Backing a trailer less than half the size of tow rig can be challenging,empty 10' boat trailer behind long box crew cab for example.
I have a customer with a stick and staple 45 foot pusher motorhome, he hauls his toys in what he calls his garage, a 26 foot stacker race car hauler, in it he has 2 road bikes, a side by side ATV a Zodiac and his M3 BMW. He lives in his SSMH 8 months out of the year.
As mentioned briefly here - there are web sites that help with battery calculations but do not forget that most batteries have a recommended percent of usage or "draw-down" so you don't damage the batteries while discharging. Follow the manuf recommendations - they are pretty low percentage-wise so you will need much more capacity than you might think - although it sounds like some guys here, in actual experience - are getting away with much less battery.
bevans6.........slipstick.......How many people didn't know what you meant? ;D
Quote from: solodon on October 16, 2014, 05:44:24 PMbevans6.........slipstick.......How many people didn't know what you meant? ;D
Come on, Don. Since most of the people here have dirt that's a lot younger than they are, the only ones who don't know what a slipstick is are the ones who only counted with pebbles in the dirt outside their cave.
So back to the inverter question.... ;)
I have been doing some reading and learning and it looks like the higher the voltage the lower the amperage and thus lower the heat and up the efficiency. Now some of this info came from a solar-cell board and they are living off of these battery/inverters and are looking for the max. So my question is since my bus is already a 12v system and I have nothing already for 24v would it be worth the effort to redesign things to accommodate a 24v house battery bank for inverter purposes? My alternator and starter are 12v and all my lighting will be 12v so that introduces quite a bit of work to go from 12v to 24v back to 12v :o I can't see that would be worth the trouble to save a few dollars on buying a 24v inverter versus a 12v one and then spending more money on converters. Now I would also, in theory, gain more usable Ah's and have less stress on the batteries. My goal isn't to live off the grid, my goal is to be able to run essentials while the occasional boon docking where I can't use my generator and maybe run 120v items while driving and short boon docking. BTW, I have my eye on a slightly used 8kw Kobota diesel so this might just all be a moot point anyways but I'm trying to learn as much as I can ahead of time.
My current idea for this bus will be 6 6v golf cart batteries, each at 230Ah, a 3-4kw ish Magnum Invertor/charger/switch, and the 8kw Kobota genset. Maybe about 200w-300w worth of solar panels as well, haven't decided if they are worth it or not.
I have another question about the battery bank as well. I will just be using one 8d for the engine starting and maybe the coach lighting outside, like the headlights and such. I plan on using the golf cart batteries for all of the rest of 12v needs including the inverter. How is the best way to charge the golf bat's from the 200+amp alternator while driving and keep them separate from my starting 8d? And should I have a way to charge/maintain the 8d while parked? And lastly is there a good way to "jump" the 8d in the rare event it died and I need to start from the golf bat's?
Thank you all for the information.
Eric.
Eric,
I wrestled with the 12 vs 24 volt dilemma when we were buying our inverter as well. There are a lot of advantages to a 24v system --less heat, smaller wires, higher amperage capability. But with that comes the pain of the issues you mentioned --system is already 12v, alternator for 12v charging, having to have a fairly complicated battery layout to keep the 12 and 24 systems separate. While it is most certainly doable, I found that just sticking with 12v was the path of least resistance, and I attempted to minimize most of the 12v negatives by keeping the inverter as close to the battery bank as possible (much cheaper cable costs that way too ;) ).
The inverter we decided on was the Victron Multiplus 3000va 50a. I've been fairly happy with it and I like a lot of its features like power-assist boost, the ability to be stacked with additional units for higher capacities, and all of the monitoring capability it has. It's price is inline with a lot of the other pure sine-wave inverters out there. And on that subject, if you don't know what a pure-sine-wave inverter is, do a google search and there will be a lot of useful info to read through; but short story, you want one :)
At least if you want to run traditional house appliances like a microwave.
Even if you have a huge generator, you'll still want something between it and the house AC systems. It allows you to buffer the load on the generator a bit and gives you future options for controlling shore power vs gen vs house batts. The inverter is not just for inverting a battery load, but for managing the whole system.
As far as batteries themselves, we have three different battery systems and we keep them discretely separate most of the time. We have the coach batteries for starting the bus and a few of the 12v coach systems, we have a house battery bank for inverter capacity and some 12v loads in the house, and a single car battery to start the generator.
My inverter manages charging the house batteries and it is quite adept at that.
I have a plugin type heavy-duty charger to maintain the coach batteries. I think you'll definitely want to keep a good (managed) trickle charge on those to keep them healthy.
For the gen battery, I have a switch that allows me to charge it with a timer from the coach charger. It only gets occasional use and I just put a top-off charge to it every few weeks or so.
As far as charging on the road, I installed a relay, with a switch inside the coach, that allows me to pair the 12v house and coach batteries to one another. By default the alternator (it's a generator actually but for ease of term reference :) ) is plugged directly only to the coach batts. The relay switch allows me to charge both going down the road. I would not recommend this as the only way to charge the house batts as they prefer a more "controlled" and "intelligent" charge, but it suffices for the relatively small amount of time we're running the air (or heat) while en route and still have good usable AC without draining the house batts.
Once we're at the new site, the inverter resumes its previous duty to manage them.
We have enough capacity to run the AC for about one hour on batteries and we have about an 800AH system. Keep in mind that with lead-acid you have both a maximum discharge amount and discharge rate to watch. The max you should discharge a lead-acid, regularly, is about 50% of capacity. So an 800ah system is in actuality 400ah usable.
The rate of discharge is also quite important and it's a function of the battery's ability to deliver the required power over a specified time. While you can discharge an 800ah system in 20 minutes, doing so will damage the batteries over time vs discharging it over several hours.
Hope that helps and sorry for the loooong post :)
Good luck!
George
Thank you George,
Why do you have a separate battery for your gen-set? Why not just tie into your coach battery? And do you have a way to jump the coach in the rare event they go dead? Yes I plan on getting a pure sine wave inverter as I will be running a house fridge, a/c, and tv's, some of which if not all will be native 12v already and I'm looking at getting 3 of those radio/dvd head units for rv's to run in each room. Plus the laptop's and printer. ::) Now I know most of these won't be necessarily running all at once on the inverter but I don't want to have to worry about plugging in something and frying it cause I don't have a good inverter. I will have to look into the Victron. The Magnum I'm looking at has some great things included with it, it has a built in charger for the batteries and a switch plus the power sharing as well. The remote console looks handy too. I think the Magnum had like a 100 amp charger as well, something very high and somthing like a 50 amp switch. Your 800Ah system, how many batteries and what kind is that?
Thank you,
Eric.
Keeping a separate batt for the generator is an insurance policy in essence. If I run down my coach batteries, then I can at least start the generator and use it to recharge the coach batteries for another shot at starting the engine. It's the way the PO had it configured and I definitely like having it. Keeping them seperate keeps whatever caused the coach batteries to drain from taking the gen batt with it.
I'm glad you asked about jumping the coach batteries if they're dead :)
I actually do. I have another relay hooked up to a momentary contact switch (inside the coach) that allows me to temporarily pair the house batteries to the coach (different than the previously mentioned linkage). Doing so allows me to in essence use the house batteries to assist the coach batteries in starting the coach. Now this is not something I would do often, since deep-discharge batts are not ideal for starting, but they would suffice in the rare emergency situation. It's all about having options on the road ;), and when it's your home and shop and transport mode the more options the better :)
The magnum is a good unit as well and I looked into it too. Its power-assist functionality seemed less functional than on the victron and it doesn't have the ability to be paired like the victron can (although I'm sure there's a way to run a pair in some special parallel config).
The victron has a 200 amp charger that will actually overload the pedestal if you're not careful and it does a great job managing the varied requirements of deep cycle house batts.
The victron also has a 50amp (AC) switch. Make sure you get the 50mp model though. The 3000va unit is sold as a 50a and as a 25a.
The one downside is it only has one 50amp leg. If you're not aware, 50 amp from the pedestal is 2 x 50 amp lines and right now my line2 is just capped off and not used. Someday I might hook up a bay plug to it or something, but 50amps total has been more than adequate for our needs (2 air units, fridge, water heater, small oven, and a bunch of computer bits). Not all running at the same time of course, but time managed appropriately to not exceed about 40 amps at any one time.
On that subject, I'd also strongly suggest you get a "surge" protector; more appropriately called a line-condition tester. You never know what kind of power you'll get from an rv park and I've seen some crazy stuff that our unit has protected us from. We have a progressive industries inline 50amp protector and it's worth its weight in gold. There are also plug-in pedestal type protectors, but those seemed to have a big "steal-me" sign attached to them, lol.
Our setup is 8 6v golfcart batteries at 200ah per, for a total of 800ah @12V. It's a whole bunch of big batteries stacked one next to the other. On our bus the PO placed the batteries in an area at the front of the bus ahead of the front bay. Really nice setup. Not sure if that's the way the 4107 was configured originally, but all of our batteries are at the front of the bus, as is the inverter.
I plan on replacing the lead-acid with lithium as soon as I find that bottomless bag full of cash that I've been looking for, lol. Seriously though the price of lithium is coming down so much that it's almost a direct competitor with lead acid and certainly AGM (if buying new); and it's a much better battery technology that is longer lasting, lighter, less maintenance intensive and is able to deliver 80% of its capacity without skipping a beat.
Baby steps though, but it's on "the list".
Quote from: Geom on October 17, 2014, 11:56:00 AMKeeping a separate batt for the generator is an insurance policy in essence. If I run down my coach batteries, then I can at least start the generator and use it to recharge the coach batteries for another shot at starting the engine. ... I definitely like having it. Keeping them separate keeps whatever caused the coach batteries to drain from taking the gen batt with it.
Yep, me too, for the same reasons.
some worth while reading here:
http://www.busconversions.com/bbs/index.php?topic=24105.0 (http://www.busconversions.com/bbs/index.php?topic=24105.0)
Specially here when you get to this part:
"If I were doing Odyssey over again, one of the very few things I would change would be to eliminate the chassis/start batteries altogether and go with a single bank, just as Bob suggests, with the proviso that the generator has its own separate start battery. The generator, of course, can charge the main bank via a charger once it's started".
What compartment are you referring to? The spare tire compartment? or the one right behind the drivers seat where the HVAC use to be? I also have a 4107 and would love to see how you did your compartments. Sounds like a very similar setup as I'm looking at doing. I don't think I'm going to carry a spare tire. The PO who started the conversion raised the floor inside along with the roof line but didn't try to utilize the space under the raised floor area up front. It's just framed in with 1" steel tubing with plywood screwed down right now so it's very easy to redesign right now. I'm thinking maybe fresh water tanks but that's just an idea. I still don't have the bus with me yet, I plan on picking it up in a few weeks :) :) :) :)
Quote from: eagle19952 on October 17, 2014, 02:02:02 PM
some worth while reading here:
http://www.busconversions.com/bbs/index.php?topic=24105.0 (http://www.busconversions.com/bbs/index.php?topic=24105.0)
Specially here when you get to this part:
"If I were doing Odyssey over again, one of the very few things I would change would be to eliminate the chassis/start batteries altogether and go with a single bank, just as Bob suggests, with the proviso that the generator has its own separate start battery. The generator, of course, can charge the main bank via a charger once it's started".
For my vote I like having the discrete systems in the "just in case" category. We've drained our house batteries on several occasions, when we've lost pedestal power and started inverting; without knowing it. In that scenario, I still like the option of being able to start the bus, independent of that event; or if the scenario in reverse having a reserve amount of CCA for starting, fed in from the house batts.
In addition to that, I intend on someday replacing the house batteries with a completely different technology (lith) and I definitely don't want to use those as starting batteries.
Using your house batteries as start batteries also necessitates having a whole bunch of batteries to buffer that high of a load demand. A starter can easily draw 400+ amps at cranking, if I understand it correctly.
While combo batteries are in theory capable of both duties, starting and deep-discharging require two completely different physical demands of the battery. A starting battery is great for high quick bursts of a whole bunch of power for very short periods, deep-discharge being the exact opposite. And each having completely different physical traits of the lead-plate layout.
Not to step on any toes, but I would most certainly not combine the two functions.
My 2 cents worth anyway.
I agree,
I understand and like the idea of a separate battery for the gen-set though, I will think about that one. As far as combining the chassis and house together that might work for some but I have a very wonderful wife and 6 kids that are going with me, but with that said they don't understand all of this and I may not always be there, I might work else where from time to time, and I need this to be um.... wonderful wife and kids proof! ;D I'm going to stick with at least a single 8d for the chassis and a bank of 6v's for the house with an emergency start solenoid to start from the house if need be.
Quote from: daddyoften on October 17, 2014, 10:43:57 AM
Yes I plan on getting a pure sine wave inverter as I will be running a house fridge, a/c, and tv's, some of which if not all will be native 12v already
I'm in agreement with
robertglines1. You are on a budget, most everything you want to run is either 12V (and doesn't need an inverter) or is too big of a load for the battery bank you are describing (and hence needs to run off the genset).
So why do you need a large battery bank or inverters that will cost $1000s?
I suppose an inverter could be useful if you want to run A/C while driving (if the bus A/C doesn't work anymore) and want to power it off the alternator (which is 12V). In that case, get an inverter just for the A/C units, and then you probably don't need a battery bank that big, just enough to act as a sort of "ballast" for the energy going from alternator -> inverter -> A/C.
Furthermore, you don't even plan on boondocking regularly. So why not just run the generator when you are parked to power A/C or the microwave or when you need to recharge 12V, and otherwise live off 12V or shore power as planned?
Quote from: daddyoften on October 17, 2014, 02:45:03 PM
What compartment are you referring to? The spare tire compartment? or the one right behind the drivers seat where the HVAC use to be? I also have a 4107 and would love to see how you did your compartments. Sounds like a very similar setup as I'm looking at doing. I don't think I'm going to carry a spare tire. The PO who started the conversion raised the floor inside along with the roof line but didn't try to utilize the space under the raised floor area up front. It's just framed in with 1" steel tubing with plywood screwed down right now so it's very easy to redesign right now. I'm thinking maybe fresh water tanks but that's just an idea. I still don't have the bus with me yet, I plan on picking it up in a few weeks :) :) :) :)
On our 4107 it's laid out as follows:
Driver side:
Behind the driver's seat is the gas tank and it runs the full width of the bus. I'm fairly certain it came from the factory that way.
Behind it is our Onan 7.5 KW diesel genset.
It consumes a good sizable chunk of space and is abutting the front bay.
Passenger side:
The area where the main wet/dry air tank is, immediately under it are the starting batteries.
In between the space for the genset and the air tank area is an empty space that is directly beneath the steps inside the coach. It's big enough for 8 220ah golf cart batteries. There is an access panel door from inside the front bay to get to them, or you can crawl under the air tank from the side. Getting inside that space is a bit tricky and not something I wish to do regularly (for battery maintenance for example). So I have also installed an automatic battery watering system that is a life saver. Taking the PITA chore of watering the batteries to a simple 2 minute process of squeezing a pump from a distilled water bottle a few times (Another item worth its weight in gold) :)
The inverter is inside the front bay towards the outside, passenger side.
There is a distribution panel under and slightly behind the air tank and it makes getting 12v into and out of that area very easy, clean, and logical and I highly recommend a similar setup.
There is a short, 300amp fused, cable run to the distribution panel from the inverter.
The PO actually lowered our floor (4" I believe) and it made a HUGE difference in the amount of headroom inside the bus (roof stayed the same) and a grown-man can stand in the middle of the bus without bumping into the ceiling or AC (air) vent. :D
This is the way our Bus came, so I'm not sure what was originally in these spots, but we do not have functional bus AC (nor want it) and we still have our spare tire (which I DO want, even with a coachnet membership :) ).
Our water is as follows:
Fresh is 3 30 gallon tanks under the bed. I have mixed feelings about that, but it definitely has advantages. Less bay space used, less likely of a freeze in cold weather, easier accessibility for work on the water system. Its disadvantage is the large potential for a water leak (which has already happened to us and ruined the carpet In there). Granted, that was caused by my dumb-assery, but dumb-assery happens, lol! I intend on pulling those tanks and replacing them with a single 100 gallon, thick walled single-rolled-piece tank and redo some of the plumbing runs (also on "the list", lol) but it's functional as is for now.
Waste water is in bay 2 with separate gray and black tanks stacked on one another. They consume about 2/3 of that bay, leaving a still usable 1/3 for additional storage.
I had a friend build me a sliding tray in both bays to make getting to either storage space easier. One "drawer" is the full width of the bay1 and is just slightly less than the full length (with room for the inverter). The one in bay2 is fitted to the entire available space.
If you'd like I can snap a few pics to clarify if needed.
Quote from: daveola on October 17, 2014, 03:27:46 PM
I'm in agreement with robertglines1. You are on a budget, most everything you want to run is either 12V (and doesn't need an inverter) or is too big of a load for the battery bank you are describing (and hence needs to run off the genset).
So why do you need a large battery bank or inverters that will cost $1000s?
I suppose an inverter could be useful if you want to run A/C while driving (if the bus A/C doesn't work anymore) and want to power it off the alternator (which is 12V). In that case, get an inverter just for the A/C units, and then you probably don't need a battery bank that big, just enough to act as a sort of "ballast" for the energy going from alternator -> inverter -> A/C.
Furthermore, you don't even plan on boondocking regularly. So why not just run the generator when you are parked to power A/C or the microwave or when you need to recharge 12V, and otherwise live off 12V or shore power as planned?
Daveola brings up an excellent point. If you don't intend to boondock or intend on running a heavy AC (power) load while en route, then you can probably forgo the inverter and batts, for now. If you'll mostly be pedestal hopping, then just get a good line-protector and run that to a transfer switch with your genset on the other side as an input and your breaker box as the output.
When using the genset, make sure to allow sufficient time (upwards of a couple of minutes) for the generator ramp up to load. Don't apply a heavy load immediately after starting it. Most generators have controllers that do this automatically but a little extra insurance doesn't hurt.
We no longer have bus AC and do intend to boondock eventually, so large battery capacity and a solid inverter was a necessity for us.
I'm reconsidering my setup, a lot to figure out. Thank you all for your advise and information.
Next question in this series.... :-)
I was first sold on getting an inverter/charger/switch as all one unit. I really liked the simple install and only one unit to install, but after some research it might be better to have 2-3 different separate pieces. What are peoples experiences with either all in one units or separate pieces?
Thank you,
Eric
If you get an all in one unit, anything that fails will leave you unable to use the other two functions.
A separate inverter, charger, converter is my way.
It's just two schools of thought. One thought is that all the functions are completely intertwined - charging the battery, switching between sources, generating the electricity - that it makes more sense to have one unit that controls all of the functions at once. The other thought is that you can do that with separate boxes, which is possible, but you have to work at it to have the charger come on and off automatically when the inverter is or isn't working, that sort of thing. Many people start out with separate systems thinking that is the better way (I did exactly that) and then go to the other way (like my Magnum 4024) when the first way doesn't work very well. My lower cost (it was still bloody expensive) inverter died, and my 24 volt battery charger wasn't strong enough. My transfer switches were just fine, mind you. It's also quite difficult to get an auto-start generator working well in a fully separate system.
Brian
I had stacked Traces a 12v system for 4000w the only problem I had with the Trace was the charger sometimes we were with out a inverter for 2 weeks while being repaired, after the last repair I never turned on the charger
I bought a Iota charger with the IQ4 as far I know it's still going strong after 5 years and it stopped the bulging of the 1st battery in the string. My theory on a battery bank is what goes out has to be put back in some way
I agree with the other comments about having more redundancy and usability in discrete systems, but it is much easier/simpler and much less error prone to have as few pieces as possible doing the work.
For us we have an inverter to manage the charging of the house batteries and switching between an inverted load or the pedestal.
I have a seperate auto-switch to control between the generator and the inverter/pedestal. Although I could in theory link the gen control to the inverter, if the inverter is smoked, I like being able to quickly work around it and at least still have some power from the gen (or pedestal).
I also have a pretty beefy charger that I use to manage my start batteries and gen battery. In case of an emergency it can be moved wherever.
Quote from: luvrbus on October 25, 2014, 05:42:09 AM
I had stacked Traces a 12v system for 4000w the only problem I had with the Trace was the charger sometimes we were with out a inverter for 2 weeks while being repaired, after the last repair I never turned on the charger
I bought a Iota charger with the IQ4 as far I know it's still going strong after 5 years and it stopped the bulging of the 1st battery in the string. My theory on a battery bank is what goes out has to be put back in some way
If you hook up your positive lead from your charger or combo inverter to the first batteries pos and your neg from the charger/inverter to the neg side of your last battery it usually takes care of the problem of boiling the first battery in a group.
Iota is a good smart charger IMO
My little bus has both shore, genny and inverter capabilities (a converter as well) and while I trust computers, relays, automatic switches and the like everywhere else, I chose to go with a manual system rather than automatic switching when it comes to powering up my bus. Paranoid, probably, but I used up my free "survive an electrocution" card when I was a child and now make sure I know that any stray electrons will find their way back to their source without using me as a---short---cut. Each of my systems has its own hot, ground and neutral circuits accessed one at a time by a single 3 prong RV style pigtail which powers the high voltage breaker panel. I also test the shore post for proper wiring before hook up to the bus. I kid myself that manually changing my power source helps me keep my mind in training but I still haven't forgotten the real reason.
Oh boy! Last night I was looking up the Vectron units and thought I was sold on them. Yes the automatic and all built to work together idea sure sounds nice. But if one breaks.....=-O I'm still learning.....:-)
Look at it this way. If you have the Victron and it breaks, you'll not need the switch part because the Victron will be out of the circuit, same as if any inverter had failed. You can buy or carry a $50 charger from Walmart that can be substituted in about a minute and keep your batteries charged in a pinch. So going with three units actually doesn't save you from anything very important or messy, and three units increases the possibility of a failure anyway, three things to go wrong instead of just one... ;D
Brian
Victron those are fun to get worked on installed in a RV it has to go back,we had 2 in the boat and what a rip off from the marine dealer to repair the Dutch made things, they are little shy on repair centers across the US
Quote from: daddyoften on October 25, 2014, 10:43:20 AM
Oh boy! Last night I was looking up the Vectron units and thought I was sold on them. Yes the automatic and all built to work together idea sure sounds nice. But if one breaks.....=-O I'm still learning.....:-)
If the inverter gets smoked, you can bypass it and run directly to your breaker panel. Since it's not working, your house batteries are also no longer in play. Putting a decent external charger on them will top them off until the inverter is fixed.
As far as the likelihood of it
getting smoked, your milage may vary, but we've been using ours quite heavily (including some hot summer bay temps) for about 6 months (not a lifetime but...) and it's run like a champ with few issues. The only issue (and I suspect the problem is likely elsewhere) is with the boosting capability when boosting a load over 40amps. It does great when boosting <20amps but at 40 it acts... strange. That's only on boosting (when drawing more than your pedestal plug can offer (like driveway surfing on 20amps). It runs fine with direct power and it can't invert more than 2500w anyway (the 3000 va unit) :).
Luvrbus is right though, if you have to have them worked on, they will require being shipped back to the vendor as there is no one around that works on them. I would think that is true of other brands, but I'm not sure.
Their main US office is in Maine I think. Their tech support people are actually pretty helpful and quite responsive (at least from my experience). I don't know what would happen in a warranty replacement or repair. I would think with a replacement they can use US inventory, a repair might be more complicated.
I would definitely get an external switcher for the gen. Mine has 3 legs, 2 in and one out.
One in comes from the line-protector (from the pedestal) the other from the gen.
The out goes to the 50a in-feed on the inverter. Then the out from the inverter goes to the breaker box.
If the inverter is out of play, for whatever reason, I can shunt the in/out around the inverter quite easily, until it's fixed.
As said earlier, I also have a different charger to use for the start batteries that can be moved to service whatever battery bank I want.
Good luck!
I just love the 100% auto aspect. My coach does exactly what it was designed for, provide me with whatever I need whenever I need it.
If when dry camping it needs to recharge batteries it does so by starting the gen, if the thermostats call for AC units to be turned on when off of shore power it will turn the gen on too. If everyone is watching TV, cooking, doing whatever and using a fair amount of power it will of course turn on at a preset voltage setting, so the batteries are never in danger of being damaged.
In my younger days I didn't mind doing some of the manual things but I have come to trust the complete auto systems and so for me it works the best. Most everything I can control and monitor from the net and IPhone so it makes it even more convenient. Tells me if the coach is to hot, to cold, or to humid turns things on and off to keep the bays at the right temp in the winter so nothing freezes. If I lose shore power for some reason then the Aqua Hot diesel heater takes over. If someone enters when they aren't suppose to it will take videos and send me pics in an email.
I would encourage anyone to go with the latest equipment that you can afford, don't be afraid if it is computerized and auto, it just makes life easier.
My biggest problem is getting time to take off