Before I Spend...does this wiring look right?

[HotHeadFubar]

Hi all,

Sorry its another newbie post with a wiring diagram.... I have an Eco-Worth 1100w PSW Inverter which is just not going to cut it in the workshop for anything other than charging the power tool batteries... Well ok it will probably do more but anyway. I am looking at 'upgrading' the system to a 3000w PSW Inverter, This One actually and have been doing calculations for days and chasing wire sizes all over the place. I 'THINK' I have this close but would welcome people with way more know how than me to take a look and let me know if I am,
A) as i hope, being over cautious with things and leaving room to move to 24v at some point, or
B) going to burn the place down in flaming glory

I figured a 500A shunt would give me plenty of room to move and still monitor batteries.
Expected 2.5Kw should be more like 2 - 2.5, peak at 3.5 on some startups.

Its a workshop its powering, not all of it, just some of it some of the time until I get brave and go full on

Thanks for any advice, and if you have to blow it apart please tell me why/where I went wrong!

 

[ScrodusGargleRotten]

I certainly wouldn't put 40 amps thru 11 awg
I would use 8 awg.

Just me probably

You also should fuse the solar charge controller wire near the battery.

A short on 11awg with that battery could flame in 3 seconds.

I'm probably wrong. Or am I wrong on that?

 

[HotHeadFubar]

Ahh yes, sorry, Think that would be a typo on my part....... the panels are 12V 120w, VOC 24.5, Short circuit current 6.24, Max Current 5.94,
So would be more like 24amp?


I didnt think about fusing the SCC, thanks for that. I'll something on the order list

 

[Koyaanisqatsi]

Need to know what solar charge controller you are using. We might make other suggestions based on that. Get one that does both 12v and 24v if you want to prep for later upgrade to 24v. The inverter only supports 12v, so you might rethink that or be ready to replace it later.

On the shunt, ONLY the battery negative connects to one side and everything else connects on the other side. You have your solar charge controller going directly to batt neg. It should go to the system neg of the shunt.

You need an ANL/CNN or MEGA fuse on the positive lead of the inverter and the solar charge controllers. One for each.

Need a Class-T fuse on the positive lead of EACH battery.

I suggest getting a couple bus bars, one for system negative and one for positive, so you're not attaching inverter and solar charge controller directly to the battery terminals.

 

[Koyaanisqatsi]

Depending on which solar charge controller you get, you might be able to connect the panels as 4S or 2S2P, rather than 4P. It would result in higher voltage and lower current on the MPPT input, requiring smaller gauge wire for the same job

 

[Koyaanisqatsi]

Also, if you're buying the batteries and the solar charge controller and inverters new, you might as well just go with 24 volt to begin with. There's no reason to start at 12 volts and then change to 24 volts unless you have 12 volt equipment that you need to support and can't or don't want to buy a DC to DC converter.

If you do start with 24v get a 24v battery, not two 12v batteries. Batteries in series require balancing, and that can be a pain.

 

[ScrodusGargleRotten]

Need a Class-T fuse on the positive lead of EACH battery.

I think that is not needed since the system is 12 v

 

[ScrodusGargleRotten]

Hold on now. I was reading 12v but your diagram is wired in series for 24v

What is it??

 

[Koyaanisqatsi]

I think that is not needed since the system is 12 v

Class-T is needed even at 12V

 

[HotHeadFubar]

Hi all

Thanks for detailed answers, really appreciate the advice and you taking the time.

Its a 12v system at the minute, 4 x 12v panel parallel, 2 panels into 1 connector 2 connectors into 1, 1into SCC. 2 x 100ah battery parallel.
The original setup instructions has it wired in like this: , the Inverter is nowhere near up to the job, which i should of realized originally.



SCC is a 12/24v. Actually this one SCC

Regarding the fuses, would these ONES work? I'll add fuses to the shopping list...lots of fuses

So updating with the suggestions it would look better like this? I've missed a fuse between the battery Positive and the bus bar though



Hopefully that makes things a bit clearer

 

[Koyaanisqatsi]

Are your batteries Lead/Acid or LiFePo4?

Battery fuse setup is a little wonky in the new pic.

With lead/acid, you only need one fuse for both, between the battery positive and the bus bar. Batteries connected to each other in parallel.

But for LiFePo4, each battery positive should be connected through a fuse to the positive bus bar. And each battery negative connected to the same bolt on the shunt. Wires on the batteries should all be the same length, to help balance current between them.

Also, these bus bars and fuses are awesome (if a bit pricey): BEP 2024 Catalogue

 

[HotHeadFubar]

They are both LiFePo4 batteries. Thanks for sticking with me and checking the plan, really appreciate it.
I've made the changes on the wiring plan and will check out those bars and fuses. I'll get the new cupboard built for it all and start ordering some bits i think,

Thanks again for the advice everyone