| Author |
Message |
Ethan Tuttle (Mrert) (65.248.194.177)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, March 30, 2004 - 8:53 pm: | |
Ok I have read every posting on batteries and setups i can find and i am lost! I am new to the conversion thing and have had a motor home and fifth whell triler in the past. I am doing all the work my self. I had a bad start right when i Got my 1981 eagle when the cluch went out on the way home with it. I am past that though, Put the new clutch in along the side of the road and now have the rig home. I just bought a 2003 never used travel trailer that got hit in the side for $2000 . I got two 13500btu acs, one 35000 btu furnace, frig, stove, and many other items needed for this conversion. I have a onan 6.5 kw gen ready to set in ,the bus curentley has a 12 volt system, and uses 2 8d batteries.i am ready to setup the house batteries. I just talked with a freind that is a tech for a cell phone company. I can get 1700ah batteries from him the first of the month. he said there is nothing wrong with them, they are just changeing them out. I plan to make the rig mostly 12 v, and see no reason not to run the gen when i need ac, most of the time i have post power when i go places. So running the ac on an inverter sounds nice but not totaly nesisary for me. I do plan on removing the orignal ac and heat system, except for the drivers area.
I am looking for sugestions on to many things here and loosing my self! lol! Long day at work! well I am open to thoughts and sugestions on how to charge them. Thank you
I think I have a good start on the supplies i need.Now just some good suggestions and ideas and i will be on my way. I have decided 200 gal potable water and one 260 gallon waste tank(because i have one already) do to the fact i have one wife and six kids rangining from 4-17 years of age. I could never keep water in the 100 gal tank on my trailer and keep the blk/ gray tanks empty.
Thank you! The new Nut (well the wife will tell you i have always been a nut!)
Ethan Tuttle |
TWO DOGS (65.179.200.188)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, March 30, 2004 - 11:02 pm: | |
MY Eagle is a '78....so ..house batterys....well ...it's kinda like a bank account....how many depend on how much you are going to draw out...I'd say 95% of the time ,Im hooked up to the elec. co, so ...I have two 12 volt batterys like you are talking about getting...mainly ...when I'm on the road...need a few lights ,my watter pump so I can flush the 'mode & maybe..some 12 volt local t.v...you can't draw anymore out than you have deposited...the two batterys did me fine while I was on wal-mart parking lot in Dallas for 4 days...but...can't imagine how many flushes you & the wife & all them kids..I have all my tanks in the back bay...55gallon fresh,55 gallons black/grey,60 gallons propane.20 gallon hot water heater & pump for camp water..hope that helps..or ask more questions |
Cory Dane (66.155.188.200)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, March 31, 2004 - 12:41 am: | |
Well we all have our ideas, dont we?
I am pretty solid on the thought of 24vdc to the inverter, that source cable for 12vdc need to be big and heavy as well as short while the 24vdc cable carrys half the amperage. I tend to keep the amperage down, never did like testing the limits of technology.
Ok, inverter size, type, VDC source, battery size, for this info, I will give you the link to get some TRACE work sheets.
http://www.aaaffordablesolar.com/2.html
Now at the bottom of the page, open the user guide, in the back pages there are some work sheets for loading, formulas and battery requirements. If you can figure out the formulas, make an EXCEL sheet and put the formulas in there, makes figuring your needs a lot easier.
My normals suggestions come from my experiences from my C class RV.
Of course, everyone has a different motive or use for the conversion they are building.
My thoughts are generally for longevity (such as dry camping).
My goal was to get as close to being able to camp considering a shore electrical connection as an option or for a periodic charge.
You must realize that if you must run the Air Cons, you need either be on shore or genset. The Inverter and batteries could never support them very long.
For an extended stay, it is helpful to include Solar Panels, "IF" or how much you may be interested in this power source would be up to your research study results.
My experience with the RV type furnace with the dc voltage SUCKING fan has been bad. When the fan drops the battery voltage down, the safety circuits in the furnace see low voltage and prevent the furnace from igniting, and you get cold or you have to run your engine.
My answer to this was to purchase two furnaces that run on propane and require no power and are vented. These are marine units and will run till the propane tank empties.
My frige is a three way, 120vac/12v control and propane/ 12vdc. Operating on Propane will consume the least power.
My stove is also Propane, again a savings on electrical energy.
It seems that the most economical lighting to date, other than candles, is florescent and you can get 12vdc bulbs to fit normal 12vdc type fixtures as well as RV type ceiling fixtures.
Hmmm you say you are 12v, if you mean the engine Generator is 12v then you will need to go with the 12v supply inverter. Note that your generator will have to supply double the amperage to the inverter that a 24vdc inverter would. I would OVERSIZE the 12vdc cable that will be source to the 12vdc inverter.
JUST a thought, we had a recent conversation about batteries that came from a cell phone company and the cells. They turned out to be NiCad cells and the conversation seemed to think that NiCad cells would not be the best choice because of their operating charactoristics. You will need to check up on that.
I think you might need to rethink your water tanks. If you only have 200 gal waste tank, you will overflow the waste tank after you reach the 200 gal capacity. potable to waste is usually about 1 to 1. If you were to separate the black and grey water, that tends to go something like 40 black and 60 grey.
Water storage will forever be a problem for you if conservation is a big problem for you. There is a difference between living in a home with sewer and water supply and hauling your own water supply and waste tanks. It is a learning trend.
Well hope I gave you some ideas to mull over, welcome to the community. The board here is very open and willing to help you with your questions, use it as an information source. Between the archieve and the users you should find a usable answer.
Look forward to hearing more of your conversion as you go.
"Imagine Your Dreams"
cd |
CraigS (65.202.123.254)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, March 31, 2004 - 7:58 am: | |
Hi Ethan,
I have a couple of thoughts. If you remove the air except for the drivers area, then your passengers will get very hot. To run one roof-top while driving you will need to run your gen-set... unless, you run the roof-top from the inverter. A roof-top might take about 10-12 amps at 110VAC. That would mean about 100-120 amps at 12VDC from your engine alternator. If you were setup for 24VDC then you could use smaller battery to inverter cabling(even tho I used 4/0 for mine for peace of mind). You would also need a 24VDC alternator added to your engine but at 24VDC the amp draw to run the roof-top would be 50-60 amps. By the way, that would be per roof-top. As you can see, there are many ways to get the job done. The 24VDC I'm suggesting would be for your house system only, leaving the original bus voltage the same for starting, headlights, interior lights, etc.
HTH, Craig S |
DaveD (142.46.199.18)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, March 31, 2004 - 9:30 am: | |
If you are not planning to use an inverter for ac while on the road, I would suggest a power converter/charger such as the Magnetek 7300 series. These are solid reliable units (We had this type in our last motorhome and have one in our MCI conversion)that provide space for breakers for any 120V ac circuits, as well as fuses for the 12V circuits. This type of converter automatically switches from battery to ac power when the shore line is connected and maintains the house batteries without overcharging them. Cost is reasonable at about $250.00 (plus the ac circuit breakers which are not included but can be purchased at most hardwares, building supplies or electrical supplies stores). At present we have two 12V deep cycle batteries for our house system separate from the 2 12V 8D starting batteries. I plan to add more house batteries; so far we've been fine because there are ususally just two of us travelling and we normally are no more than about two days max. between being connected to shore power.
Dave Dulmage
(MC-8) |
James Maxwell (Jmaxwell) (66.81.42.178)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, March 31, 2004 - 10:50 am: | |
I have not seen or heard of 1700ah cell batteries and it seems like a very high rating compared to the normal Grp 31 usually found in that service, which are rated at 120-150 amp reserve. Many cell service batteries are AGM type rather than standard flooded cell which eliminates the necessity of cell servicing and cuts down considerably on corrosion. Also, the AGM type do not discharge hydrogen gas as they recycle it into the cells; true sealed batteries and very suitable for house batteries. On the retail market, they are still very pricey, generally 3-4 times the price of flooded cell, given equal reserve ratings.
As used batteries, they are not at their peak in performance, regardless of what u may be told by people servicing these battery banks. They are normally sold as a 5-10 yr. service life and generally they start to get replaced in 3-4 yrs., for various reasons, mostly because of a failure of 1 or 2 batteries in a bank. Industry wisdom seems to dictate changing the entire bank rather than just the batt that went bad once the bank reaches a certain age.
I just installed 8 of them as my house bank on the recommendation of 3-4 people that I know using them for that purpose, all satisfied, considering the low cost of these used batteries. I wanted a new bank of Lifelines, but hesitated at the $1600 cost, but jumped right on the $200 price of the used ones, figuring that at $25 a pop I can afford the experiment. Mine will be on the Trace charger all the time except for when I'm dry camped, where I have 500 watts of solar to make up part of the drain on them. Rest of the time it will be up to the genset. Ask me in about a year and I will give you my appraisal of used cell tower AGM batteries for house service. |
Sean Welsh (Sean) (64.81.73.194)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, March 31, 2004 - 12:10 pm: | |
Careful with those 1700ah batteries -- if that's really the rating, it's likely a 1.2 volt NiCD. These were very common in the remote-site end of the telecom business a few years back.
You'll need to string 10 of these together to get a 12-volt system, so 10 batteries give you a total of 1700ah. Also, you will need a charger that has the special settings for NiCD batteries. Lastly, these batteries were designed for float service -- I'd be surprised if they give you more than 30 or 40 good cycles. NiCD "memory" may already have reduced the effective capacity of these as well -- you may need to "recondition" them.
-Sean |
Henry R. Bergman, Jr. (Henryofcj) (63.224.197.10)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, March 31, 2004 - 4:09 pm: | |
Also to add to the above, I would be willing to bet they ARE Ni-cads with only a nominal 1.2 volts per cell.
If they were higher voltage, each cell would weigh several hundred pounds each. Even a 1700 amp hour cell.
Is going to be a very big heavy mommy. How they could even be physically installed would be a big problem.
Let us know what your discover with your super battery source. Maybe your type of batt will be the way to go. |
Nick Morris (Nick3751) (65.117.139.135)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, March 31, 2004 - 5:58 pm: | |
Got a related ? for you guys. If you go with a 24v system how would you then fix it so that you can use your house batts to "jump" your starting system? I saw a switch to do this on a class C I rented out west a while back and like the idea. I've got a 12v starting system so I was leaning towards 12v house system as well for the above reason. I would like to go with 24v if I could fix a jumper as the same time. |
Sean Welsh (Sean) (64.81.73.194)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, March 31, 2004 - 6:49 pm: | |
Nick,
Simplest way to do this is to just jump the start batteries from the lower "half" of the 24v house bank (in other words, put your emergency start relay between the center tap of your house bank and the high side of the start bank). Use a battery equalizer such as those made by Vanner, Sure Power, and others, to "equalize" the depletion of the two halves of the house bank. You'll need to set the equalizer up in parallel with the batteries -- the equalizer alone will not supply enough current for starting purposes.
-Sean |
Jim Stacy (209.247.222.85)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, March 31, 2004 - 10:07 pm: | |
If you don't need 24 volts, why mess with it? It is so easy to work with when both systems are 12 volt. They can be tied together on the road and also when the inverter is charging. They can also be tied for emergency starting.
Twelve volt lights and appliances are simple without messing with equalizers and center tapped banks. Wire size is not realy a big issue compared to the problems of dual voltage systems. The only reason to use 24 volt at all is if the coach HVAC system requires it.
My 3000 watt Heart inverter (12 volt) runs one roof air on the road with no problem. We have a bank of five 8Ds for house and two 8Ds for start batteries. The DN50 puts out over 250 amps at 12 volt and keeps up very nicely. The batteries are from Sams. $100 each, last set lasted over 5 years. Yhis is a real life system that has worked for over 5 years, not some untested theory or wish list for fancy batteries that cost five times as much and usually don't last any longer in real service. With 240 watts of solar, we have boondocked for 30 days at Quartzsite with satelite tv and microwave and no damn gen set running. Gen set only needed to run AC when parked and we rarely use it.
I guess I bettter get off my soapbox and shut up.
Thanks for hearing my two cents worth.
Jim Stacy |
DonTX/KS (66.82.9.53)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, March 31, 2004 - 10:24 pm: | |
Nick, it seemed to get lost in the discussion, but Jim is very correct. IF you already have a 24v bus (as I did) ONLY then consider a 24v system at all. In your case, a 12 inverter is in my opinion, the ONLY sensible answer, just as it was with Jim's bus. |
RJ Long (Rjlong) (66.229.97.200)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, March 31, 2004 - 10:29 pm: | |
Hey Jim - Was that by any chance an SA-8 soapbox???
LOL
RJ
PD4106-2784
Fresno CA |
Nick Morris (Nick3751) (65.117.139.135)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, April 01, 2004 - 7:36 am: | |
Ok that sounds like a plan. Now I got another one for you. Would it be cost effective to isolate each batt in my house bank? If it's worth it that would save my bank if one batt goes bad for some reason. I've heard on this board and others that golf cart batts work well because they recharge well. I'm just not sure if using twice the batts with 6v if I'm going to need to isolate each one would be worth it.
Thanks for the help everyone. |
FAST FRED (65.154.177.188)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, April 02, 2004 - 5:37 am: | |
On a choice between 6V and 12V HOUSE batts , the 6 V usually get the nod.
There is usually more lead inside the 6V than the 12V in the same sized case.And the lead is the power.
With only 3 cells to keep seperate and wired together (rather than 6) the case has more space for lead and uses fewer seperators.
Golf carts are usually a great choice for hard working batts, weather you want to pay for this or better quality is up to you.
A golf cart will usually be rated for 200 to 400 deep discharges (take a look at the Trojan site) .
Thats draw down to almost 50% and recharge.
The question is DO you need 300 drawdowns that deep in 4 or 5 years?
Many folks that only camp on weekends boondicking only do this a few times a year 10?
So in 5 years only 50 deep discharges could be handeled easily with a cheap Sams Club 8D , and normal charging equippment.
No load monitoring , 3 or 4 stage recharge , nothing.
However if you plan on hitting 4 Corners 3 months a year or will be sitting on unimproved BLM campgrounds 100 days , a time , the choice of golf carts would work better.
In fact for this service Surettes ,(good for over 1000 discharges +) Big Bucks , and all the monitoring and charging goodies will be required to survive , with out tossing the batts every 6 months.
Install what YOU need to have the lifestyle you enjoy.
FAST FRED |
Doug Dickinson (Dougd470) (65.161.188.11)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, April 02, 2004 - 9:31 am: | |
Fred raises a good point on battery simplicity/value/functionality.
It makes a lot of sense to use the same house battery string voltage as the coach battery string - not mix them up. I am using a vanner - but only because I have some small 12V loads, but the coach and house batts are 24V strings.
One word of caution about selecting batteries is that if you plan on using the inverter charger to charge both house and coach batts, or use the coach system to charge house batts while underway - you will need to be sure you are using the same type of batts (i.e. flooded cell vs gel cell or AGM) in each system. The charging specs are different and if you gang different batts to the same charger, it ain't gonna work out very well.
Doug
St Louis MC9 |
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