Electrical Plan Review

[edpelo]

I have spent the last few weeks researching and learning the basics of electrical in preparation for wiring up my van. I have come up with the following schematic and am nearly ready to start buying the parts. I figured I'd post it here hoping that a few of you might look it over and make sure I didn't make any obvious blunders or just provide your opinion on the setup.

A few notes:
-Wire sizes will be either manufacturer recommended or sized appropriately based on length and potential load.
-I'm planning on using this battery combiner. Is it okay that it's rated at 225 amps and the batteries combined would be around 244 amps? Or, more likely, is it referencing the alternator's amps in which case I could use this smaller one?
-There will be a fuse on the battery bank pole and a disconnect switch there as well.
-I'm planning on using this solar charger and this panel
-I'm planning on using this inverter charger for connecting to shore power, charging, and running a few things periodically off the batteries like a small microwave
-I know I could stand to use another solar power to really max my off grid time out, but I don't think we'll use the batteries regularly and heavily enough to warrant the extra cost.

Please, if you comment, back up any opinions with the logic or experience that helped you arrive at them so that I can better understand and learn. Thanks!

 

[edpelo]

Here is a better image of the schematic

 

[fluffyprinceton]

Consider one of these -
http://bluesea.com/products/5511e
To give you the option of using your house batteries to start your truck if the start batteries fail/discharge unexpectedly. It would replace your battery combiner.
http://www.jamestowndistributors.co...tems+Add+a+Battery+Charger+and+Switch+Package
It's a bit more$ but I've installed many & have them in my boat & camper & they are quality - Moe

 

[edpelo]

Consider one of these -
http://bluesea.com/products/5511e
To give you the option of using your house batteries to start your truck if the start batteries fail/discharge unexpectedly. It would replace your battery combiner.
http://www.jamestowndistributors.co...tems+Add+a+Battery+Charger+and+Switch+Package
It's a bit more$ but I've installed many & have them in my boat & camper & they are quality - Moe

I thought about going that direction but opted for the combiner I linked because it takes care of everything automatically and waits for the engine battery to be charged fully before redirecting charging to the coach batteries. Also, while the jumping feature is nice it's not super important to me. Everything that could drain the battery will be rewired to the coach batteries (stereo, lighting etc). The headlights are wired to turn off with the vehicle, so its unlikely I'll need jumping. In the case that I do, I can always remove a battery from the coach and do it manually. A pain, but a very unlikely one. Thanks for the thoughts. Does the rest of the schematic look sensible? I'm kind of looking for overall design critique before I spend the bucks and implement...

 

[fluffyprinceton]

When you price the cable size needed to start your engine from your house bank...ouch - it's a more expensive option than just the combiner/switch so I can understand not needing the switching feature.

Without seeing the actual components it's hard to judge their suitability but it looks straight forward to me except why run the fuse block off the solar charger? Maybe put a distribution bar on the way to the inverter - run both the inverter and the fuse block off that bar. If you put it off the solar charger your wire size will have to match your fuse block amperage...much,much greater than the little bit from your solar panel. Also there's no good reason your solar charger would be built to carry that amperage. I assume you know about wire size charts for 12 volts...so you sort of design these things around efficient ($$$ efficient that is...) choice of wire size & run lengths which need to be in your schematic at some point...
Also any instrumentation? Volt or amp meters?
In the run from the alt to the combiner it's the alt amperage that's critical - that's all that runs on that cable so why 225 amp rating? Without running your house bats power back to your starting bat there's no reason for the big combiner.
There are 4 circuits here
1... Starter bat to combiner to house bats
2...House bats to fuse panel/distribution bar
3...House bats to inverter
4...Solar panel to charger to house bats

I'd add an instrumentation circuit - at least a volt meter...

circuits 2&3 are very similar in power draw so they could be grouped together more or less...Hope that helps. Moe

 

[edpelo]

When you price the cable size needed to start your engine from your house bank...ouch - it's a more expensive option than just the combiner/switch so I can understand not needing the switching feature.

Without seeing the actual components it's hard to judge their suitability but it looks straight forward to me except why run the fuse block off the solar charger? Maybe put a distribution bar on the way to the inverter - run both the inverter and the fuse block off that bar. If you put it off the solar charger your wire size will have to match your fuse block amperage...much,much greater than the little bit from your solar panel. Also there's no good reason your solar charger would be built to carry that amperage. I assume you know about wire size charts for 12 volts...so you sort of design these things around efficient ($$$ efficient that is...) choice of wire size & run lengths which need to be in your schematic at some point...
Also any instrumentation? Volt or amp meters?
In the run from the alt to the combiner it's the alt amperage that's critical - that's all that runs on that cable so why 225 amp rating? Without running your house bats power back to your starting bat there's no reason for the big combiner.
There are 4 circuits here
1... Starter bat to combiner to house bats
2...House bats to fuse panel/distribution bar
3...House bats to inverter
4...Solar panel to charger to house bats

I'd add an instrumentation circuit - at least a volt meter...

circuits 2&3 are very similar in power draw so they could be grouped together more or less...Hope that helps. Moe

Great comments. Thanks for taking a look. In the case of needing a jump, I was planning on just disconnecting one of the house batteries, carrying it around front, and using jumper cables. Its so unlikely that I definitely don't want to spend extra $$ on it. The cables for the combiner can be much smaller without that.

In one of my previous generations of the schematic I had the fuse block running directly of the batteries and not the solar controller. I changed it at some point, I think because I noticed the solar charger has a a third set of terminals for DC out and thought it would make more sense to use that than to hook in directly to the battery. I really have never even heard of a distribution bar before now. Not turning a lot up on the net either... can you link me to an example or a product on Amazon? I searched for "12 volt distribution" on Amazon and it turned up the fuse block I'm already planning on purchasing which adds to my confusion.

I do know about wire size charts and am in the process of adding the correct sizes to the diagram. I'm planning the layout in the van to be as efficient and inexpensive as possible.

I'd like to add a meter of some kind so that I can tell where my batteries are at. Everyone seems to recommend a meter cable of displaying cumulative amp hours... but they seem awfully pricey. I'd prefer not to shell out much more cash as this project is maxing my budget out as is. Think I can get by with just a regular volt meter wired off the battery? Or could I wire it off the fuse block? I certainly can't be flying blind all the time.

Got it on the alternator amp rating for the combiner. I won't we going from house batteries to engine so I'll size it based on the ~75 amp alternator.

Thanks again!!

 

[edpelo]

something like this? http://www.amazon.com/Sierra-Intern...e=UTF8&qid=1357766173&sr=1-2&keywords=bus+bar

 

[fluffyprinceton]

Bluesea systems are a great reference - poke-around. http://bluesea.com/files/resources/...o_Blue_Sea_Systems_Fuses_and_Fuse_Holders.pdf

I should of said "bus bar"...http://bluesea.com/category/82

WestMarine is another great reference...It drives me absolutely nuts when somebody suggests "#2 wire should be ok" without knowing the amps & length of run. Just Use the Chart.
Wire size chart - http://www.westmarine.com/webapp/wc...catalogId=10001&page=Marine-Wire#.UO4c4nfbN8E

Use good connectors, I love the waterproof kind but they are overkill for land based systems...http://www.westmarine.com/webapp/wc...Type=SimpleSearch&viewTaskName=SiteSearchView

These Marine resources are great for learning...you don't have to buy their stuff but they provide good free training...

You put a volt meter pretty much where you want - it just measures the voltage of the bats. I like one that measures two bat banks so you can keep track of both house & start. At least get one for the house so you don't discharge them too much too often...Amp hour meters are nice but just pay attention to your voltage & you'll be fine. I like basic AGC glass fuses. Cheaper, visible when blown & available. Although matching the fuse type of your truck makes sense & the fuse block aren't much more expensive...Moe