800W Solar Powered Sprinter Conversion. (pics)

bee · Mar 3, 2013

The current is always divided amongst the batteries in normal conditions.  When would they not share the load evenly?

wrcsixeight · Mar 3, 2013

Under large loads, the batteries in the middle will not work as hard as the batteries closer to the edges, where the power is taken from.  Balanced, thick wiring can minimize this.

offroad · Mar 4, 2013

on many car batteries to prevent corrosion, those red and black sponge insulators are put under the terminal connections. assume dirt-dust becomes a conductor after a while. are these needed in all battery connections?  or should the maintenance of lead acid batteries just include a wash diwn with a baking soda water mixture. at least once a year?   know that at our hospital we replace batteries once every two to three years in most of the battery equipment. what is the battery replacement interval for lead acid in solar systems?

wrcsixeight · Mar 4, 2013

Battery life expectancy is directly related to how they are treated.  How deeply they are discharged, and how quickly they are returned to full charge and how often they are cycled.  Anywhere from 5 months to the chronically undercharged to 15 years for the batteries never discharged and held at full charge in moderate temperatures. Keep the baking soda out of the cells.  Some cell caps designs make this difficult.  The felt pads are just grease/oil holders.  Overtightening of battery terminals is a primary cause of excessive battery terminal corrosion as the gases can escape from the overtightened studs where they penetrate the battery case.  The felt pads impregnated with grease partially seal the cracks and slow the green/ white corrosion build up. Keeping the battery(s) clean is a good idea.

bee · Mar 4, 2013

Okay one more try to get my point across.  If I fail no big deal, its not like car manufacturers even bother with catastrophe fuses.  You could say they are optional. <img rel="lightbox" src="/post/<a" class="bbc_img"><img rel="lightbox" src="http://i278.photobucket.com/albums/kk98/russellbeyman/Untitled_zps8e0fdbde.jpg" class="bbc_img"> class="bbc_img">

ickkii · Mar 4, 2013

Sorry if it doesn't seem like I get your point bee, I do. I'm legitimately not sure what will happen in this case. I have a circuit app for my tablet I'm going to play with and test it out. As I said before 180 amps could be running through the line up until they reach the batteries, at which point the current is divided like you said. The fuses WILL be oversized when the current is divided amongst the batteries, but before it gets to that point I dont want more than 180 amps being divided amongst them. Each individual battery shouldn't charge higher than 225Ah x 10%=22.5A, so for each 12v bank, your way, the fuse should be about 45A for each bank. 45A x 4 banks = 180A total. My worry is that the 45A fuse will pop before the current on the 180A line makes it to the battery. In parallel the fuses may stack like you said so that would fix the issue, but I'm not sure it works like that because the power may not be equally distributed yet. wrc, the way the batteries are wired now compared to originally uses equal length strands of cable between each battery, connected to the main line so the difference should be very small.

wrcsixeight · Mar 4, 2013

If a catastrophic fuse is desired, do not run individual ones to each battery but a larger one between the (+) stud and the other side of it, not one for each battery.  I don't use them, I just make sure the cables cannot chafe and ground out.  I can and do start my engine with my house batteries, and while my digital ammeter does not instantly read large currents, I have seen fuse blowing numbers (150+)during engine cranking. Fuses can present the resistance that we are seeking to reduce by using thick cables in the first place. There are some fuses which attach right at the battery post itself, and do not need to be spliced into the cable, which presents more areas for resistance and failure. http://shop.pkys.com/Blue-Sea-Systems-5191-Single-Terminal-Fuse-Block-30-300-Amp_p_82.html Keep the marine industry in mind when looking at parts for an RV Build.  Bluesea systems makes great electrical products, where as many RV stores/products cater to the less knowledgeable who can just afford to throw money at a problem and have someone else do it, and remain proudly ignorant of how their systems work.

ickkii · Mar 4, 2013

Yeah you're right. battery fuses are just too much of a pain and I'll have everything else fused so there's really not much reason to bother. The whole reason to have the circuit breaking switches there is so I can turn off power sources to prevent excess amperage. I'm really not going to be power starved enough to need more than 2 power sources on at the same time. I looked at the EV charging rates when I was at walgreens and it's only 49 cents a KWH, that alone is affordable enough to compensate for any gaps in available power. the solar guys I talked to seem really adamant about their fuses (even between panels) and I just don't get the point in having so many. A fuse on each of the power sources should be sufficient. I'm just going to remove the battery fuses altogether and get to work on finding a good 160a isolator. I do like that link you posted though, I've found quite alot of goodies in the marine market, I actually was looking for ac's there too not very long ago, but boats tend to use water pumps for their air conditioning.

ickkii · Mar 4, 2013

On the air conditioners, I am pleased to say with some comfort that they WILL work with this project. I did some hardcore digging online today and found other companies that sell these particular units (some even for cheaper - saw a listing at $900), and found 'no-idle' air conditioning units, which would seem like something others here would be familiar with. So those will be the ones I opt for since there's no way they can run off of an engine that isn't even on. http://www.accclimatecontrol.com/application.htm#Ambulance http://ecycle.com/No_Idle_Air_Conditioning_for_Police_Cars.html the second link, as the title suggests, is an air conditioner used in a few of today's hybrid police cars. I don't know how many of you have ever been on the business end of a cop car, but I can personally vouch the air conditioning is the best aspect of the back seat of a police interceptor. will be replacing almost half of the image in OP soon with a more functional and detailed outline now that everything is coming together more. Thanks again to all of you who have tossed ideas back and forth, it's helped get this far. I hope others on this forum can benefit from these ac units since there hasn't been much of a standard from what I've seen.

bee · Mar 4, 2013

The way I see it there are 2 reasons to fuse. Reason 1:  To protect a piece of electronics.  Usually there will either be a fuse built in, or in the installation manual it will specify to put a fuse of xxamps in line to protect the device. Reason 2:  Protect the wires.  In this case a catastrophe fuse. Example:  I ran a 0 gauge wire from my start batteries -> underneath my truck -> and into my truck camper to charge the batteries while driving. I installed 2 catastrophe fuses one at my start batteries(would be the alternator in your drawing) and another at my house battery bank (in other words at each end of the cable right next to the power sources).  The reason for this is because if the insulation gets damaged underneath the vehicle and the copper wire touches frame (which is ground) it could drain both my house batteries and my start batteries.  This may produce enough heat and sparks to catch my truck on fire. Hence the name "catastrophe".  These large fuses located by the power sources is my last ditch effort to stop my vehicle from burning to ashes. So in your drawing you have a fuse at the alternator and a circuit breaker switch on the other end. The wire between those 2 points is protected from catastrophe.

bee · Mar 4, 2013

I hate to keep sounding negative, but there is something you might have missed. The accclimatecontrol site lists amp draw of there model 25111   17,000btu ac system at only 12.7 amps.  However if you look closely it is a 110v system.  thats 1397 watts The police cruiser site lists the amp draw at 8000btu at 90 amps and 12v. (which doesn't include any fans just compressor.  Thats 1080 watts. Most ac systems cycle so I wonder if those specs are averaged?

ickkii · Mar 4, 2013

It's cool I appreciate you looking out. There are dozens of 12v <30a systems there as well, they're averaged at maximum draw, that 110v system is one of the only AC driven air conditioners on there, DC is preferred. I've sent this company another email about the sub-40A setups because the other site has yet to return an email. This is what I had in mind. http://www.accclimatecontrol.com/heatcool/22035A000A.htm http://www.accclimatecontrol.com/heatcool/22090A000C.htm

ickkii · Mar 5, 2013

wrc how does this look? http://www.amazon.com/PAC-PAC-200-200-Power-Relay/dp/B000CEBXRS/ref=pd_sbs_auto_3

wrcsixeight · Mar 5, 2013

That looks like a good solenoid.  I like this one: http://www.texasindustrialelectric.com/pdf/SAS_4202.pdf 200 amps continuous, Silver contacts. http://www.texasindustrialelectric.com/relays.asp While I use a manual Guest switch similar to this to isolate my engine battery

A Dumb  Continuous duty solenoid activated by the blower motor circuit(which is off during engine cranking) would be my second choice. Followed by the single sense Blue Seas automatic charging relay. http://www.bluesea.com/products/category/Automatic_Charging_Relays.

vokus · Mar 5, 2013

I just wanted to trow this in the mix. InverterSealed AGM batteries.DC Charger GeneratorAux Fuel CellGenerator Sound Proof BoxJust an idea.. Added stealth, no solar panels on the roof. Guaranteed 55 amps in to battery, day or night, rain or sunshine.With a hitch mount, and a sound box you can make it invisible and almost sound proof. The less parts to mess with, the better right? This is the smallest dc gen they offer, you can pump alot more amps in to your batteries if you want to...    <img rel="lightbox" src="http://s15.postimage.org/8islxob9n/Untitled.png" class="bbc_img">

ccbreder · Mar 5, 2013

The greased felt pads protect the terminals from corrosion on the under side of the battery terminals. The top still have to be cleaned and grease coated to prevent corrosion. With flooded cell battery, the fumes from the caps will cause corrosion and acid slick on the top of the battery. Flooded cell need regular maintenance. If your battery has any cracks from any reason, replace it. I'm with Bee, fuses in parallel share the load and multiply the protected amps. The battery bank can put many more amps than the battery rating during a short. The 100 amp hour is 200 in 30 min. think how much for 1 minute. You need a fuse in the main cable leaving the total battery bank, close to the battery bank, sized to the capacity of your wire. The capacity of your wire is a function of it's gauge and the length. This larger fuse protects your wire and battery bank from nasty things. Other smaller fuses are installed at the individual components sized to the need of the component. Componant= ie; solar panel, alternator, refridge, light circuit, and such. There are 12 volt refrigeration units, costly. There are 110 volt with inverter. May be less $ long term. Also could be run from a generator or shore line in camp. I favor the Honda inverter generators. Very quiet. available 2000 watt or 3000 watt for backup 110 and also for charging with 12 volt taps.

ickkii · Mar 5, 2013

The main reason the dometic refrigerator was even considered was because it's a low power 12v 45w refridgerator. Power consumption much higher than that would be better left to just buying cold food/drinks fresh and immediately consuming them. They are kind of pricy but I find value behind energy efficiency, and it's easier to justify when considering it's a home refrigeration replacement. For the fuses I decided I'm going to get a 4th breaker switch for the main line as a system shutoff, it will be sized to 180 amps so is a failsafe for any occasion where I forget to cut off solar when the alternator is feeding the batteries. So there will never be enough current being fed the line to do any damage to the bank. The dc load (inverter, ac, vent, refrigerator, cig receptacles, lights) will be fused. That's the step I'm on now. The inverter is trickier to fuse because it needs to be rated pretty high to compensate for charging and power draw. I think the product website will tell me what fuse to use. The rest is pretty simple. It's mainly the LEDs that will be the most work because they require regulation since they only are 3.7w. I have experience working on custom luxeon led lightsabers though so I know which components to use, it's just minor adjustments for 12vs instead of 3-9v. At 4 power sources I'm going to cut it off right now because it's about as complex as I'm willing to make it. Free charging from solar Semi-free charging from alternator $0.49 a kwh from EV Shore power through inverter as an option for when the opportunity presents itself. The way everything is sized right now just fits in the back, not really room for much more. I looked at generators but there's not enough room for it and it's cheaper in the long term to pay for EV charging than it is for gasoline. Trojan has a nice battery maintenance guide for their flooded cells, it will be a biweekly thing. No big deal, better than mowing the yard am I right? I'll just set my tablet up to give me a heads up every other sunday to take care of it.

wrcsixeight · Mar 5, 2013

A residential fridge running on an inverter is doable, but a waste of battery power.  The Danfoss compressors used by Dometic have adjustable speed compressors. The higher the rpm, the faster the cool down and the higher the amp draw but shorter duty cycle. The speed is adjustable by a resistor in the thermostat circuit.  My Vitrifrigo came with a 270 ohm resistor to run the compressor at 2500 rpm.  Minimum is 2000, max 3500.  I removed the resistor, as I do not need the quick cool down, because it is always running.  And the slower the compressor runs, the more efficient. Mine pulls about 2.5 amps at 12.6 volts, and runs less than 20 minutes per hour in 75f ambients to hold interior under 36.5f You do not need to shut off the solar when the alternator is helping to charge the batteries.  I've had 4 different charging sources going at the same time before.  Solar/alternator/and 2 automatic battery chargers.  Once the batteries near ~14.5, some of the sources drop out of the mix on their own.  They do not need or require oversight.  Only manual chargers do, and only when they get the battery up near full charge. When the batteries are low, they will happily gobble up the amps whatever their source is. They will not ask for more than they can handle provided the voltage regulator keeps them under 15 volts. For the DC distribution, hooking an individual ATC fuse block to the house batteries simplifies/organizes wiring for the devices that draw under 25 amps. You do not want a bunch of individual fuse holders for the lighter draws.

That is the one I have, and still a few open circuits to use in the future.  Just feed 12 volts to the center bolt. Remember when fusing, you are fusing to protect the wiring, you are not seeking to find a fuse 0.25 amps higher than the capabilities of the alternator or devices which will be asking for the battery amps

ickkii · Mar 5, 2013

yeah I keep ignoring that the batteries are going to use everything on the line. I swear I'm going to stop because I keep giving myself unnecessary headaches lol.  So would that power being generated that's unused by the batteries go to the dc load?  The resistor idea you mentioned is pure genius man! I'd usually neglect stuff like that due to warranty but it's definitely something I'd consider, is it really as simple as removing it? And you're also dead on with me not wanting to use multiple fuse holders, fuse blocks it is! I wonder how this would cooperate with the bus bar, have you done this?

ccbreder · Mar 5, 2013

All the jumping about refrigerators and air conditioners has me head spinning. I want to thank you for this thread an dhope you keep us posted with your progress. Thanks. http://www.cruisersforum.com/forums...y-installation-new-ac-power-system-29667.html

800W Solar Powered Sprinter Conversion. (pics)

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