I built a mobile battery bank and inverter combo, what do you think? (Pictures) - Page 1

[ARCHIVED THREAD] - I built a mobile battery bank and inverter combo, what do you think? (Pictures) (Page 1 of 2)

Posted: 11/26/2011 4:38:28 PM EDT

I posted this on another fourm also, so Im sorry if you are reading it again.

Well been board today so I decided to put this together for part of my backup power supply. I went way over budget on this one. I tried to make it as safe as possible for inside my house use.
I bought a lot more expensive batteries than I wanted, however I think I will be happier in the long run. I now have to take the wood back off and round the corners and paint it. I also have to tidy up a few of the wires.This is a work in progress project, so I will be making improvements over the next few weeks. I can't wait to see how long the batteries will last running my fridge,TV and lights around the house.
When charging I plan on taking the tops off the boxes so to let the batteries be cooler. I also placed a small amount of space between the batteries so as to have cooling room.
The inverter is a 3000 watt continuous and 5000 surge (Wish I had spent the extra on a pure sine inverter).
The batteries are four sealed 12 volt 105 ah AGM Deep Cycle batteries, giving me a total of 420ah.
I used 2 Gauge wire. And the batteries are balanced now on how the inverter draws power.
I made the unit mobile so I can roll it where I want with ease.
I placed 2 very large marine grade power switches on the unit to cut power to the inverter when not in use, The inverter still draws ampage even when off, the switches prevent this.
I placed a 175 amp fuse on each battery in case of a short.
In the event of a power failure I can run my fridge, outside motion lights, TV, and any and all lights in the house at night and not have to listen to a generator. I can get about 2 nights maybe 3 nights with my fingers crossed between charges. There are a lot of varibles as to how much drain is on the battery bank each night. In the day I can run the generator and don't mind the noise.
Best of all its mobile, I can pull it down the street to my moms if need be or even a neighbors house. I can roll it any where here on the property when 110 volt is needed, to run something.

Posted: 11/26/2011 4:47:29 PM EDT

[#1]

Nice.
How much $$$ did that project cost you ?

Posted: 11/26/2011 5:05:20 PM EDT

[#2]

That's awesome!

Posted: 11/26/2011 5:08:03 PM EDT

[#3]

Looks good Rodney!

Posted: 11/26/2011 5:08:31 PM EDT

[#4]

Quoted:
Nice.
How much $$$ did that project cost you ?

I would have to dig out the receipts, I am really not even wanting to know, however off the top of my head, I guess about $1200 .
I had a bunch of the small parts and cables, it seems to run anything I plug in it and for a long time.

Posted: 11/26/2011 5:09:29 PM EDT

[#5]

Nice job and great pictures.

Posted: 11/26/2011 5:12:29 PM EDT

[#6]

I have been looking at that same inverter.

Have you by chance tried running florescent lights off it?

Posted: 11/26/2011 5:16:21 PM EDT

[#7]

That Sir.....is sexy.....

Posted: 11/26/2011 5:19:35 PM EDT

[#8]

I'm really not trying to be a killjoy...

According to this table the maximum ampacity of 2 gauge wire is 130 amps, assuming the wire's insulation is rated for 105*C. For lesser-rated insulation the ampacity is lower. The purpose of the fuses is to protect the wire in the event of a short circuit. Using 2 gauge wire, a 175 amp fuse offers no protection; the wire will probably melt before the fuse blows.

Also, at full power, a 3 kW inverter will draw over 250 amps from the battery bank. Surging to 5 kW the inverter will draw over 400 amps. This is WAY over the ampacity of the 2 gauge wire. If you intend to use the inverter at anything near its capacity you need to beef-up the connection to your battery bank. Consider using two runs of 2 gauge wire for each connection between the inverter and the batteries. You'll also need to either use heavier wire for your battery interconnects or replace the fuses with lower-rated ones (perhaps 100 A).

In any case, your battery bank will not be able to sustain a 250 A draw (3 kW AC out of the inverter) for very long. Much less than the 1.5 hours simple math would suggest. If you intend to run the inverter at full power you're going to need a bigger battery bank.

Posted: 11/26/2011 5:21:50 PM EDT

[#9]

Quoted:
I have been looking at that same inverter.

Have you by chance tried running florescent lights off it?

I ran my ceiling lights in the garage and they are floresent and they seemed fine, however I will do some testing and see how those lights work if you think there could be a problem. But I do know that my plasma TV hates it, So far that is the only thing that acts funny that I know of.
My old tube type TV's seem to run fine also.

Posted: 11/26/2011 5:33:02 PM EDT

[#10]

Quoted:
I'm really not trying to be a killjoy...

According to this table the maximum ampacity of 2 gauge wire is 130 amps, assuming the wire's insulation is rated for 105*C. For lesser-rated insulation the ampacity is lower. The purpose of the fuses is to protect the wire in the event of a short circuit. Using 2 gauge wire, a 175 amp fuse offers no protection; the wire will probably melt before the fuse blows.

Also, at full power, a 3 kW inverter will draw over 250 amps from the battery bank. Surging to 5 kW the inverter will draw over 400 amps. This is WAY over the ampacity of the 2 gauge wire. If you intend to use the inverter at anything near its capacity you need to beef-up the connection to your battery bank. Consider using two runs of 2 gauge wire for each connection between the inverter and the batteries. You'll also need to either use heavier wire for your battery interconnects or replace the fuses with lower-rated ones (perhaps 100 A).

In any case, your battery bank will not be able to sustain a 250 A draw (3 kW AC out of the inverter) for very long. Much less than the 1.5 hours simple math would suggest. If you intend to run the inverter at full power you're going to need a bigger battery bank.

Thanks for the info, I am running 2 positive 2ga wires, and 2 negative 2ga wires I feel this should work as this is what the manufactuer supplied. Check out this photo and you will see a total of 4 wires supplying power. And yes I know the fuses are to high, however that is the only fuses I have right now, and in the event of a total short I feel it would be better than nothing.
I did some testing on an old battery and the fuse will blow in the event of of a total short before the wire melts down.
Those fuses are $5 apiece and I hated to blow one for test puposes, however I had to know.
I will be running things that require a lot less than 3000 watts, however if I need a quick surge in power its nice to have.
I thought of running a 2000 watt inverter, but it can't handle my circular saw on start up.
THe batteries last plenty long for what I need it for, I doubt I will run at 3000 watts very long, more like 1200 watts and less, however I got it if need be.

Posted: 11/26/2011 5:41:44 PM EDT

[#11]

Quoted:

Quoted:
I'm really not trying to be a killjoy...

According to this table the maximum ampacity of 2 gauge wire is 130 amps, assuming the wire's insulation is rated for 105*C. For lesser-rated insulation the ampacity is lower. The purpose of the fuses is to protect the wire in the event of a short circuit. Using 2 gauge wire, a 175 amp fuse offers no protection; the wire will probably melt before the fuse blows.

Also, at full power, a 3 kW inverter will draw over 250 amps from the battery bank. Surging to 5 kW the inverter will draw over 400 amps. This is WAY over the ampacity of the 2 gauge wire. If you intend to use the inverter at anything near its capacity you need to beef-up the connection to your battery bank. Consider using two runs of 2 gauge wire for each connection between the inverter and the batteries. You'll also need to either use heavier wire for your battery interconnects or replace the fuses with lower-rated ones (perhaps 100 A).

In any case, your battery bank will not be able to sustain a 250 A draw (3 kW AC out of the inverter) for very long. Much less than the 1.5 hours simple math would suggest. If you intend to run the inverter at full power you're going to need a bigger battery bank.

Thanks for the info, I am running 2 positive 2ga wires, and 2 negative 2ga wires I feel this should work as this is what the manufactuer supplied. Check out this photo and you will see a total of 4 wires supplying power. Great, that should work fine

And yes I know the fuses are to high, however that is the only fuses I have right now, and in the event of a total short I feel it would be better than nothing. I did some testing on an old battery and the fuse will blow in the event of of a total short before the wire melts down. Then you're GTG

Those fuses are $5 apiece and I hated to blow one for test puposes, however I had to know.

I will be running things that require a lot less than 3000 watts, however if I need a quick surge in power its nice to have. Then you'll be fine
I thought of running a 2000 watt inverter, but it can't handle my circular saw on start up.

THe batteries last plenty long for what I need it for, I doubt I will run at 3000 watts very long, more like 1200 watts and less, however I got it if need be.

http://i901.photobucket.com/albums/ac216/Rockyriver1234/Home%20Made%20Battery%20Charger/DSCN1595.jpg

Again, not trying to be a jerk. You clearly understand how this works and the limitations of your system. My comments were primarily directed at other folks reading your thread who may not understand high-current systems as well as you do. Nice job.

Posted: 11/26/2011 8:09:52 PM EDT

[#12]

Very nice and clean. One thing that you might want to add is some powerpole connections, and some 12v cigarette lighter plugs. Maybe a digital voltmeter to monitor how much life is left til a charge is needed.

Here's my simple setup:

Posted: 11/26/2011 8:11:54 PM EDT

[#13]

Quoted:
Very nice and clean. One thing that you might want to add is some powerpole connections, and some 12v cigarette lighter plugs. Maybe a digital voltmeter to monitor how much life is left til a charge is needed.

Here's my simple setup:
http://i1201.photobucket.com/albums/bb347/myphotobucketpictures1/batterybox2.jpg

http://i1201.photobucket.com/albums/bb347/myphotobucketpictures1/batterybox1.jpg

look at 5th pic down...

Posted: 11/26/2011 8:23:53 PM EDT

[#14]

That's a thoughtful and clean job RockyR!

As far as cable size you aren't going to pull anywhere near the current your inverter is rated for with those 4 batteries for any length of time.

So for a reasonable and practical usage, I think you sized the cable just fine.

Posted: 11/26/2011 9:02:45 PM EDT

[#15]

Hey, that's clean, simple and effective. Great job! It's inspiring.

Posted: 11/26/2011 11:39:13 PM EDT

[#16]

Jeeze - That is a thing of beauty!

Posted: 11/27/2011 12:27:50 AM EDT

[#17]

Very cool.

Posted: 11/27/2011 2:04:29 AM EDT

[#18]

Very nice! I really like your use of the wagon for a mounting platform.
Here's my much dinkier solution... only an 800 watt inverter, but mine was really just an exercise:

Posted: 11/27/2011 2:48:29 AM EDT

[#19]

Nice set up.

Posted: 11/27/2011 3:18:05 AM EDT

[#20]

Rockyriver that's a mighty fine set up. I like the mobility idea.

Question, does your 3,000 watt inverter have a audible or visual alarm to let you know when the batteries are running low on charge?

Another question, the fuse you currently have are they "current limiting" type? Since those type fuses can handle "momentary" amp surges without blowing. At work we have those type of fuses for large motors with high amp draw during start up.

Posted: 11/27/2011 4:10:54 AM EDT

[#21]

Well done sir!

Posted: 11/27/2011 4:25:46 AM EDT

[#22]

Those wagons kick ass-

I've got both my generators on one. They're very hard to kill.

Posted: 11/27/2011 4:37:14 AM EDT

[#23]

It seems like a lot of work and money. Not sure what you got out of it.

I am not real worried about the wire size for something like this. The charts are all based on wire being in conduit and inside insulation and higher temps. This is in free air where it will cool better. I am not real worried about the fuses either. They are only there to deal with a short circuit and given the short lengths of wire involved they will probably work ok for that purpose.

I will point out that by code you are not normally allowed to run parallel wires under 1/0, but for something like this that will see almost no use, I doubt it matters any.

The only other thing is that with the way this is wired the battery physically closest to the invertor will see the heaviest loads.

It probably would have been better to wire the batteries in series and use an inverter that takes 48VDC as an input. Smaller wires throughout and simpler connections. Just a thought.

Posted: 11/27/2011 4:43:06 AM EDT

[#24]

Quoted:
Very nice and clean. One thing that you might want to add is some powerpole connections, and some 12v cigarette lighter plugs. Maybe a digital voltmeter to monitor how much life is left til a charge is needed.

Here's my simple setup:
http://i1201.photobucket.com/albums/bb347/myphotobucketpictures1/batterybox2.jpg

http://i1201.photobucket.com/albums/bb347/myphotobucketpictures1/batterybox1.jpg

Great thoughts, however these are mine on your thoughts.
As far as power pole connections, I wanted to keep everything that could be shorted out hidden beneath the battery covers for safety incase kids be around it.
If I need a power pole, I simply take the lid off of one of the battery boxes.
The 12 volt cig plug is in picture 5 from top.
The 12 volt digital readout is built in to the inverter and is picture 4 down from top. It seems to do OK for monitoring the batteries life.
However I am looking for a better voltmeter, I just have not found one at the price I want to pay yet.
I am forever modifying this thing, and I am open to any and all suggestions to making my project better.
Thanks

Posted: 11/27/2011 5:08:07 AM EDT

[#25]

That is Awesome. That thing turbocharged?

I like that you spent a few extra bucks for the disconnect switches.

Posted: 11/27/2011 6:57:30 AM EDT

[#26]

You did a very nice job assembling it!

I would caution however, trying to run big loads from this for long (fridge, furnace, etc). I speak with experience here, and have if you draw those batteries much below 20% more than a couple of times, you will wreck the batteries... (My first set of batteries was 300Ah at 48V, and I still wrecked them pretty quick).

If you have 420AH batteries, at 12V, then that is 5040Ah - Since you can really only 'hit' 20% of that, you have about 1008Ah you can use regularly, and that means, (ignoring the inverter losses) you can run a hundred watt light bulb for about 8 or 9 hours. I'd give your fridge a few hours.

Also, I didn't lookup your inverter specs, but it looks like an MSW inverter, which are pretty hard on motors (fridge compressor).

Posted: 11/27/2011 7:30:36 AM EDT

[#27]

Quoted:
Those wagons kick ass-

I've got both my generators on one. They're very hard to kill.

Yeah no kidding, I'ma gwine put my genny on one.

Posted: 11/27/2011 8:14:40 AM EDT

[#28]

I'd get a torque wrench (in/lb) and torque all your connections down with nuts instead of wing nuts. Loose connections cause heat and resistance.

Posted: 11/27/2011 11:02:04 AM EDT

[#29]

where did you find those wagons?

Posted: 11/27/2011 11:26:24 AM EDT

[#30]

Quoted:
where did you find those wagons?

Here is the company, im sure there is a dealer near you for them.
http://millside.ca/products/Metal-Deck-Wagons/

X

Posted: 11/27/2011 4:41:40 PM EDT

[#31]

Quoted:
If you have 420AH batteries, at 12V, then that is 5040Ah

He has four 105 AH 12 volt batteries, all connected in parallel - which is 420 AH at 12 volts.

Since you can really only 'hit' 20% of that, you have about 1008Ah you can use regularly

A quality deep-cycle battery* will tolerate being 80 percent discharged at least several hundred times.

80 percent of 420 AH is 336 AH - which means that you could safely consume up to 336 amp-hours without reaching the 80 percent discharge point - and do it on a regular basis without seriously shortening the lifespan of the batteries.

*Conventional SLI automotive batteries aren't designed to handle deep discharges, and don't last anywhere near as long as their deep-cycle counterparts when discharged to 80 percent - typically, just a few times before suffering a significant, permanent loss of capacity

Posted: 11/27/2011 5:51:51 PM EDT

[#32]

Quoted:

Quoted:
If you have 420AH batteries, at 12V, then that is 5040Ah

He has four 105 AH 12 volt batteries, all connected in parallel - which is 420 AH at 12 volts.

Since you can really only 'hit' 20% of that, you have about 1008Ah you can use regularly

A quality deep-cycle battery* will tolerate being 80 percent discharged at least several hundred times.

80 percent of 420 AH is 336 AH - which means that you could safely consume up to 336 amp-hours without reaching the 80 percent discharge point - and do it on a regular basis without seriously shortening the lifespan out of the batteries.

*Conventional SLI automotive batteries aren't designed to handle deep discharges, and don't last anywhere near as long as their deep-cycle counterparts when discharged to 80 percent - typically, just a few times before suffering a significant, permanent loss of capacity

Thanks for explaining that to him, I read his post and it confused me, so I just ignored it.
Maybe I was not clear in one of my post and this caused the confusion.
The AGM batteries I have are advertised as taking 300+ deep discharges before affecting the life of battery, if that means anything.

Posted: 11/27/2011 6:08:30 PM EDT

[#33]

Quoted:
The AGM batteries I have are advertised as taking 300+ deep discharges before affecting the life of battery

Did they mention what they define as a "deep discharge"? With some brands and models, it's 100 percent discharged - with others, it's 80 percent. Naturally, a battery that will withstand 100 percent discharges 300 times would last quite a bit longer than that, if it was only discharged 80 percent.

Posted: 11/27/2011 6:40:43 PM EDT

[#34]

Do you have your batteries wired like this:

Or like this:

The top way equalizes the draw on each battery while the second way will draw on the top battery more then the lower one.

Posted: 11/27/2011 7:36:31 PM EDT

[#35]

First, I am sort of kind of wandering down a similar path. My batteries may not be as nice but it depends on my mood at the time. I am very impressed with the setup so don't take any of the following as me picking. I am learning, or at least trying.

4 does seem like an awfully nice number and while I like your wagon I am pulling a motor off a push mower with ball bearing wheels and going to use it for my battery holder. I just see me having flat tires with those wagons. But I used to work at walmart and am thinking of the wagons they had.

While it is nice that it could run the fridge, do you really see a need to run the fridge at night? I am planning to run my stuff in the morning and evening, couple deep freezes and a fridge maybe. I might make ice with the deep freezes and put the fridge stuff in a cooler. Depends on time of year and how much stuff I have in the deepfreezes and blah blah blah. This also will vary by people needing help and what not. A deep freeze making ice might be worth the hassle to keep a lot of food from spoiling.

Anyway, do you really see a need to run all that stuff at night?

How do you plan to charge up the batteries and how long does it take in reality?

While I have a decent battery charger I am kind of figuring I need something better if I am going to do this setup properly so I am wondering about real world numbers.

I have some older relatives with health problems and I am kind of figuring I might have the luxury of running a window ac unit while I sleep using the batteries, or if we can't evacuate the older relatives it will be a health need sort of thing.

If I missed the charger I will see it tomorrow when I am not tired from work and review this thread.

For those commenting about wires, better to go with 4 wires like this project or 2 wires of larger size?

I am going to have to buy the wire and want to build something like this once and later on if I want something else I would probably build a seperate setup.

I also plan to rig this setup for powering my toy hauler/camper/storage of stuff trailer. Not sure how to work that out yet but I will figure something out.

Posted: 11/27/2011 8:05:30 PM EDT

[#36]

"For those commenting about wires, better to go with 4 wires like this project or 2 wires of larger size?"

It doesn't matter a whit, 1, 2, 3 wires paralleled, whatever combination will carry the load you expect and you can round up.

Don't forget quality jumper cables as a source of wire.

It will take a heck of a battery bank to run a window A-C all night and a heck of a charging system to charge them back up.

Maybe go with a quiet genny in a housing?

Posted: 11/27/2011 8:39:45 PM EDT

[#37]

Quoted:
"For those commenting about wires, better to go with 4 wires like this project or 2 wires of larger size?"

It doesn't matter a whit, 1, 2, 3 wires paralleled, whatever combination will carry the load you expect and you can round up.

Don't forget quality jumper cables as a source of wire.

It will take a heck of a battery bank to run a window A-C all night and a heck of a charging system to charge them back up.

Maybe go with a quiet genny in a housing?

dont forget car audio shops and wielding supply shops. they will also have larger AWG wire for things like this.

Posted: 11/27/2011 10:08:31 PM EDT

[#38]

Quoted:
It seems like a lot of work and money. Not sure what you got out of it. silent, renewable power for use at night, small loads so you dont have to fire up the genny, or even short term power outages

I am not real worried about the wire size for something like this. The charts are all based on wire being in conduit and inside insulation and higher temps. This is in free air where it will cool better. I am not real worried about the fuses either. They are only there to deal with a short circuit and given the short lengths of wire involved they will probably work ok for that purpose.

I will point out that by code you are not normally allowed to run parallel wires under 1/0, but for something like this that will see almost no use, I doubt it matters any. please show me where this is posted in any code section. this is a temp power setup using 12v. i have been out of the construction business for a while but in all my years doing it i never saw a thing about 12v wiring in any house code sections so things could have changed.

The only other thing is that with the way this is wired the battery physically closest to the invertor will see the heaviest loads. if you had actually read his post you would have seen that he has it wired for equal load across the batteries which is why there is a wire running under the cart.

It probably would have been better to wire the batteries in series and use an inverter that takes 48VDC as an input. Smaller wires throughout and simpler connections. Just a thought.

as for the 12v v/s 48v, in a small system like this its easier to setup, cheaper to build and easier to find parts for locally. also, it allows you to run any 12v items you may have floating around. now, if this had been a "whole house" setup then im with you 100% on going 24 or 48v but smaller things like this, 12v is just fine. not to hijack to bad but a cart like this as well as 2 or 3 smaller systems are planed for when we move into our own house. i plan on the 2 or 3 smaller systems to run things like the TV and sat TV for the kids and charge things like the cell phones and to run my amateur radio equipment. then farther down the road is going to be wiring the house for DC and building/installing a larger system and eventually be mostly, or fully off grid with solar and wind to charge the batteries. that is a ways down the road but the smaller setups will help with saving fuel from the genny as well as powering things when we dont want to run the genny.

Posted: 11/28/2011 2:02:44 AM EDT

[#39]

Quoted:
Do you have your batteries wired like this:

http://i241.photobucket.com/albums/ff124/flytosail/12VoltParallelBatteryWiring.jpg

Or like this:

http://i241.photobucket.com/albums/ff124/flytosail/images.jpg

The top way equalizes the draw on each battery while the second way will draw on the top battery more then the lower one.

I had in the beginning my setup like in the bottom picture, but after reading I switched them around and now run my wires like in the top picture you have posted. Which is the correct way.
My batteries are balanced now. Thanks for the diagram

Posted: 11/28/2011 4:59:33 AM EDT

[#40]

I found the thread on the charging stuff, dang nice setup on both.

I appreciate the answer on the wires, I was thinking that would be the answer but I need to dig out my books on electricity and do some refreshing.

I should have mentioned that I don't think I would run the window ac all the time. The plan for everything is to mostly run it morning or night on the generator and probably only run the generator in the mornings and evenings. And then during the night if needed the battery bank could probably run the window ac unit to cool things back down.

Just having some fans moving air means a lot to me and I am still messing with some small battery powered fans and wondering about finding some larger fans that will run on DC power.

For me the battery bank is the start of a tiny solar setup. I want to have it to learn from it and mess with it and also have it for backup power.

Posted: 11/28/2011 6:43:24 AM EDT

[#41]

Quoted:

Quoted:
Do you have your batteries wired like this:

http://i241.photobucket.com/albums/ff124/flytosail/12VoltParallelBatteryWiring.jpg

Or like this:

http://i241.photobucket.com/albums/ff124/flytosail/images.jpg

The top way equalizes the draw on each battery while the second way will draw on the top battery more then the lower one.

I had in the beginning my setup like in the bottom picture, but after reading I switched them around and now run my wires like in the top picture you have posted. Which is the correct way.
My batteries are balanced now. Thanks for the diagram

Had to search the net for the photo. Great missed chance to us MS Paint.

Nice build.

Add a solar cell set up that is portable (think PVC) and a basket on the the side for the solar cells and a basket on the other side of the cart for the stand and you will be the 2011 SF Poster of the Year.

Posted: 11/28/2011 10:40:55 AM EDT

[#42]

Quoted:

Quoted:
Very nice and clean. One thing that you might want to add is some powerpole connections, and some 12v cigarette lighter plugs. Maybe a digital voltmeter to monitor how much life is left til a charge is needed.

Here's my simple setup:
http://i1201.photobucket.com/albums/bb347/myphotobucketpictures1/batterybox2.jpg

http://i1201.photobucket.com/albums/bb347/myphotobucketpictures1/batterybox1.jpg

Great thoughts, however these are mine on your thoughts.
As far as power pole connections, I wanted to keep everything that could be shorted out hidden beneath the battery covers for safety incase kids be around it.
If I need a power pole, I simply take the lid off of one of the battery boxes.

Thanks

He meant these powerpoles.

Posted: 11/28/2011 2:05:10 PM EDT

[#43]

Quoted:

Quoted:
Very nice and clean. One thing that you might want to add is some powerpole connections, and some 12v cigarette lighter plugs. Maybe a digital voltmeter to monitor how much life is left til a charge is needed.

Here's my simple setup:
http://i1201.photobucket.com/albums/bb347/myphotobucketpictures1/batterybox2.jpg

http://i1201.photobucket.com/albums/bb347/myphotobucketpictures1/batterybox1.jpg

Great thoughts, however these are mine on your thoughts.
As far as power pole connections, I wanted to keep everything that could be shorted out hidden beneath the battery covers for safety incase kids be around it.
If I need a power pole, I simply take the lid off of one of the battery boxes.

Thanks

He meant these powerpoles.

http://www.powerwerx.com/_design/powerwerx/_images/sizecomp_pp.jpg

Oh I got you now, I have a set of those, just have not installed them yet.
Thanks

Posted: 12/1/2011 2:26:50 PM EDT

[#44]

More mods were made on the battery bank today.

Mod 1
I mounted 2 LED mag lights on the mobile battery bank, one on the left and one on the right. The reason I went with flashlights was simple, I felt that if the battery bank was dead or had a problem then mounted lights that used the onboard batteries would be useless. And to give me a little insurance that I would have light I mounted 2 flashlights for insurance. Now I have quick easy access to light and they are on a quick detach mounts.

Mod 2
I finally mounted my battery level indicator. It is made by MidNite Solar and does a decent job of letting me know the charge on the batteries.
It is also compact and low draw LED and fit like a glove were I mounted it. I will be adding a toggle switch to cut it off when the battery bank is in storage and not going to be used for awhile.
I just need to figure where is best to mount the positive and negative wire for the best and most accurate reading.
This unit can be set for Flooded batteries,Gel,or AGM for more accurate readings.
Approximate battery voltages relative to
percent State of Charge.
12 Volt Battery State of Charge
11.65 - 10%
11.77 - 20%
11.89 - 30%
12.02 - 40%
12.14 - 50%
12.26 - 60%
12.38 - 70%
12.51 - 80%
12.63 - 90%
12.75 and above - 100%

Mod 3
I mounted 2 12 volt access plugs, so I can charge or use 2 things at once that use a cigarette lighter plug, I used stainless steel metal ports and removed the plastic one that I first mounted because I felt it was cheap made.

Posted: 12/1/2011 4:46:55 PM EDT

[#45]

Awesome!

Posted: 12/1/2011 5:15:45 PM EDT

[#46]

Re the Midnight charge remaining readout, you have to know what condx the reading is taken, at rest or under a load.

It just appears to be a fancy voltmeter and the same funtionality could be obtained with an inexpensive [$8] digital readout as already mentioned.

The accurate way to measure state of charge is with a hydrometer or refractometer, but since the OP's batteries are sealed, can't be done [easily].

Posted: 12/1/2011 5:36:44 PM EDT

[#47]

Quoted:
Re the Midnight charge remaining readout, you have to know what condx the reading is taken, at rest or under a load.

It just appears to be a fancy voltmeter and the same funtionality could be obtained with an inexpensive [$8] digital readout as already mentioned.

The accurate way to measure state of charge is with a hydrometer or refractometer, but since the OP's batteries are sealed, can't be done [easily].

I tried several voltmeters I had, the problem is with them after I left them on (they have internal power supply (9volt battery) they would kill the battery or the unit cuts off and I have to reset it in an hour.
But you are correct the Midnite is a fancy voltmeter, but it works great.
The Midnite is accurate only after the batteries have rested a few minutes after the inverter has been used, however if its under a light load (the inverter) the meter gives a fair indication as to where I stand and if the batteries are fixing to give out.
I figure this item will pay for itself by not letting me take those AGM batteries to far down on the charge scale. .

Posted: 12/1/2011 5:51:19 PM EDT

[#48]

instead of that battery thing do you think an adjustable low voltage alarm set at say 11.9V would be a better option? that along with one of the $8 voltage meters would let you know when your charged and when its time to charge with both an alarm and just by looking at the meter.