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Old 04-16-2018, 07:40 PM   #1
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Critique my noob Solar Setup (Diagram)

Hey all,

I am a noob and this is my first attempt at drawing my soon-to-be electrical setup as I am getting started on it this week.

I am sure there are some errors but I did my best and it'd be great if you could take a look!

Before you look I will repeat myself: I'm a massive noob. This is my first attempt lol

https://image.ibb.co/mZQGP7/Bus_electrical_system_1.jpg

couple of things:
1) I understand that ground wires should be attached to the frame of the bus. But with which wires and also how would you do it?

2) I don't know what size circuit breakers I should be using but I drew them on the diagram where I think they will be going.

3) Do negative wires also go to load centers or just positive?

Let me know your thoughts. Thanks!!
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Old 04-17-2018, 06:33 AM   #2
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Looks ok to me. Appears you are wiring the panels in series and the 6VDC batteries in series (12VDC bank). The 1500 watt inverter might be a bit overkill for the battery bank which is probably around 220 Ah. It will work though. Ideally you would have a good quality battery monitor so you know that state and can take care of them. No provision for shore power??

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Originally Posted by Jeremyc View Post
1) I understand that ground wires should be attached to the frame of the bus. But with which wires and also how would you do it?
There are several "systems" at work here so it can be a wee bit confusing. In the case of your house/solar DC system, all grounds must get back to the battery bank negative (to complete the circuit). In the case of the AC system, all must get back to the inverter. In the case of shore power (AC), all must get back to there. If you can create a good/reliable connection to the frame (and/or chassis to frame), all these grounds can be ran thru it. You can think of it as a giant ground "bus." (pun intended) That said, some folks (likely those who have fought grounding problems) prefer to run positive and negative wires to all items and use a single/common ground point. In some circles, ground loops are often discussed. I've not seen this problem on RV/bus type systems but I suspect anything is possible (an expert might be able to explain better/further).

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Originally Posted by Jeremyc View Post
2) I don't know what size circuit breakers I should be using but I drew them on the diagram where I think they will be going.
Fuses/Circuit breakers protect the wire/cable. So, you size them to match what the wire/cable can handle.

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Originally Posted by Jeremyc View Post
3) Do negative wires also go to load centers or just positive?
Typically, a generic 12VDC "load center" deals with positive cables only (fuses/circuit breakers). However; I believe some of the pre-made/do-it-all panels that are available include a negative bus (in which case you would need both pos & neg cables).
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Old 04-17-2018, 09:28 AM   #3
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Quote:
Originally Posted by JDOnTheGo View Post
Looks ok to me. Appears you are wiring the panels in series and the 6VDC batteries in series (12VDC bank). The 1500 watt inverter might be a bit overkill for the battery bank which is probably around 220 Ah. It will work though. Ideally you would have a good quality battery monitor so you know that state and can take care of them. No provision for shore power??







There are several "systems" at work here so it can be a wee bit confusing. In the case of your house/solar DC system, all grounds must get back to the battery bank negative (to complete the circuit). In the case of the AC system, all must get back to the inverter. In the case of shore power (AC), all must get back to there. If you can create a good/reliable connection to the frame (and/or chassis to frame), all these grounds can be ran thru it. You can think of it as a giant ground "bus." (pun intended) That said, some folks (likely those who have fought grounding problems) prefer to run positive and negative wires to all items and use a single/common ground point. In some circles, ground loops are often discussed. I've not seen this problem on RV/bus type systems but I suspect anything is possible (an expert might be able to explain better/further).







Fuses/Circuit breakers protect the wire/cable. So, you size them to match what the wire/cable can handle.







Typically, a generic 12VDC "load center" deals with positive cables only (fuses/circuit breakers). However; I believe some of the pre-made/do-it-all panels that are available include a negative bus (in which case you would need both pos & neg cables).


Hey there! Thank you for your response.

The panels I think I actually wired wired them in parallel with all positives connected and then all negatives connected.

The batteries I think I made a mistake in connecting all the positives and negatives as itís supposed to be wired in series and not parallel.

Each battery is 235amps. So I have. 470amp hours total. Think that is overkill for 1500 inverter??

We donít intend to hook up to shore power but the inverter I got is an AIMS Inverter/charger so if needed could that act as a place to plug shore power into? Or am I completely off here haha?

Thanks for your response!
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Old 04-17-2018, 09:43 AM   #4
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Assuming you're using 6V batteries, the battery bank will be either 235AH at 12V or 470AH at 6V. You want a 12V system.

Wiring the batteries in series will double the voltage. Wiring in parallel will double the amperage.

https://www.batterystuff.com/kb/arti...-tutorial.html

I used 4 6V batteries to attain 470AH at 12V. Depending on your power needs, you may want to add a couple batteries.

Disclaimer: I've only recently installed my electrical system and have yet to add the solar panels. Also haven't had time to test if I've got enough power to live full time....so any advice I give is worth what you've paid for it!
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Old 04-17-2018, 09:49 AM   #5
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Quote:
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Assuming you're using 6V batteries, the battery bank will be either 235AH at 12V or 470AH at 6V. You want a 12V system.

Wiring the batteries in series will double the voltage. Wiring in parallel will double the amperage.

https://www.batterystuff.com/kb/arti...-tutorial.html

I used 4 6V batteries to attain 470AH at 12V. Depending on your power needs, you may want to add a couple batteries.

Disclaimer: I've only recently installed my electrical system and have yet to add the solar panels. Also haven't had time to test if I've got enough power to live full time....so any advice I give is worth what you've paid for it!


****. Youíre right. So how do I up my amperage if Iím using 6v? Even if I add more batteries Iíll still have to wire them in series to get the desired 12v with no additional amperage.

Also, if I added 2 more batteries what would I do with the extra cables? I canít have 4 heading to my inverter and charge controller. How would I deal with that?
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Old 04-17-2018, 09:52 AM   #6
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Quote:
Originally Posted by Jeremyc View Post
The panels I think I actually wired wired them in parallel with all positives connected and then all negatives connected.
Ugh! Sorry about that... For some reason, my brain cannot keep that straight. Yes, you are correct. What you diagrammed is parallel and the preferred approach.

Quote:
Originally Posted by Jeremyc View Post
Each battery is 235amps. So I have. 470amp hours total. Think that is overkill for 1500 inverter??
6 volt batteries in series will double the voltage but leave amperage the same. So, you will end up with a 12 volt battery bank of 235 Ah. That bank will have ~117 Ah usable (staying above 50% SOC). The inverter is capable of drawing 120 amps (1500 watts - ignoring start up loads). Obviously, you don't have to work it that hard but if you do, your battery SOC will diminish very quickly. There is a whole discussion to be had about C-rate and Peukert's law but that takes too much brain power.

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Originally Posted by Jeremyc View Post
We donít intend to hook up to shore power but the inverter I got is an AIMS Inverter/charger so if needed could that act as a place to plug shore power into? Or am I completely off here haha?
Yes, I would assume that is correct (it has a built in transfer switch). That works just fine.
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Old 04-17-2018, 09:54 AM   #7
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Your only option for more power storage is more batteries.

All the batteries are wired together such that you end up with a 'battery bank'. This is done with a combination of series/parallel connections. There is one positive cable and one negative cable to/from this bank.
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Old 04-17-2018, 10:11 AM   #8
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Quote:
Originally Posted by Jeremyc View Post
Also, if I added 2 more batteries what would I do with the extra cables? I canít have 4 heading to my inverter and charge controller. How would I deal with that?
You only need 2 cables running to the inverter.

Your battery bank, with 4 6V batteries, will look something like this (depending on how the batteries are layed out). The two optimal connection points for the charging and inverter systems are shown in red and in lavender. Either pair of terminals works equally well.

Source: https://roadslesstraveled.us/wet-cel...n-wiring-tips/
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Old 04-17-2018, 10:22 AM   #9
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Critique my noob Solar Setup (Diagram)

Quote:
Originally Posted by Drew Bru View Post
You only need 2 cables running to the inverter.



Your battery bank, with 4 6V batteries, will look something like this (depending on how the batteries are layed out). The two optimal connection points for the charging and inverter systems are shown in red and in lavender. Either pair of terminals works equally well.



Source: https://roadslesstraveled.us/wet-cel...n-wiring-tips/


Ah that makes a lot more sense. So I should get 2 more batteries and wire them in series AND parallel.

Definitely wouldnít have thought of that myself lol. Thank you for the link!

Random question: Would it not be possible to wire 2 batteries in series and parallel to double Volts and the amps instead of needing the extra 2?
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Old 04-17-2018, 10:59 AM   #10
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Quote:
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Ah that makes a lot more sense. So I should get 2 more batteries and wire them in series AND parallel.

Definitely wouldnít have thought of that myself lol. Thank you for the link!

Random question: Would it not be possible to wire 2 batteries in series and parallel to double Volts and the amps instead of needing the extra 2?
Never mind this ^^ I did some research and discovered it is only possible with 4 batteries.

Another question --> My battery box has only enough room to house 2 batteries. I was thinking of putting the new 2 I now need to buy above the battery box but INSIDE the bus (i'd have to drill a hole through my floor so i could connect them all).

Does that sound stupid? There isn't really any more room for another box underneath ha...
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