Hi All,

 

My name is Dex and I joined to gain some knowledge and maybe later help some others.

 

Currently i have a 2000VA sine wave inverter with 4 x 100AH lead acid batteries (24V configuration), as it is now i have only 2 of the batteries hooked up and there is a solar panel with a small pwm solar charge controller and the system works quite well.

I am going to move the system to my garage and connect the batteries all up so that it is all 4 in 2 banks parallel at 24V which imo should give me a total of 4800W, assuming a 50% DoD i will have 2400W available.

I am basically looking to replace the panel completely and add 2 x 300-330W panels and a new solar charge controller which would recharge the batteries even if i went down to 50% DoD which i doubt.

Does that make sense?

From there i basically plan to add a small DB and wire in 2 stand alone plugs to 2 rooms - this circuit will not join my house circuit in anyway at this point, I would like to then have my house light circuits connected to this db in such a way that i can have a switch over between this DB and the existing, thoughts on this?

i have 2 primary concerns, how is this new system going to be grounded? and how do i ground the panels?

 

Thanks in advance.

image for a visual representation of what i want to do. I will also be looking for a reputable electrician to sign off/inspect and possibly handle the switch over in main DB board so for any referrals in the east rand please advise if you are able?

1. Put a changeover after your main switch in the main db. Feed the inverter in there. You must have an RCD on the output of the inverter for safety, so it makes sense to put the changeover right after the main switch, but before the existing RCD. If you don't want to put the whole main DB on backup, then you have to split the loads, put a changeover before the split part, and then you must install an extra RCD on the output of the inverter.

2. All earths must be interconnected. So simply earth the inverter to the earth bar in the main DB.

3. For the RCD to work properly, neutral and earth must be bonded (connected together) on the output of the inverter. First make sure if your inverter supports this. Some of them does this automatically. With some you can safely bond them together yourself. With a small amount of the cheaper ones (usually modified sine wave jobbies from China) you can't bond earth and neutral without blowing up the inverter. Those inverters can not be connected to the house. Don't do it.

4. Get an electrician to do it. With the exception of the bonding part and how inverters do or don't do it, they understand everything else very well. It's the same as for a generator.

thanks plonkster, is an RCD similar to an earth leakage/mains?

I have something that looks that same if i google RCD between my interter and batteries currently, does that seem right (on the red + line)?

Also do you have any suggestion for suppliers? i am finding it really hard to find somewhere that will get back to me or willing to assist currently. preferably east rand or jhb. i just want to be able to speak to someone, go there, maybe ask a question or 2, pay and take the stock.

so I found a place that it seems will actually finally help me though their pricing isn't the greatest and options are a bit limited. the charge controllers i can choose from are:  EP SOLAR 20Amp MPPT for R2650 or a 30 Amp for R3800, any opinions on these? the 325W renewsys panels are R2650 each, which is higher than what i see else where but at least i wont need to pay for shipping or anything as the place is local.

 

Also, it turns out my batteries arent all the same, i have 2 x 100AH and 2 x 105AH, i think i am going to have to connect the same ones in series and then the 2 banks in parallel, i know it isn't the most ideal situation but it is what it is and i beleive like this it will still be ok?

 

Any advice?

15 hours ago, Dex_ said:

i have 2 x 100AH and 2 x 105AH, i think i am going to have to connect the same ones in series and then the 2 banks in parallel

Yes, a 100 Ah string in parallel with a 105 Ah string will be fine. Definitely don't mix 100 with 105 Ah in the same series string.

15 minutes ago, Coulomb said:

Yes, a 100 Ah string in parallel with a 105 Ah string will be fine. Definitely don't mix 100 with 105 Ah in the same series string.

thanks for your feedback

15 hours ago, Dex_ said:

the 325W renewsys panels are R2650 each, which is higher than what i see else where but at least i wont need to pay for shipping or anything as the place is local.

Where are you situated?

Just now, stoic said:

Where are you situated?

east rand - i am considering now looking at the power store for stock. it really is a battle to get decent service it seems anywhere

On 2019/03/22 at 8:37 AM, Dex_ said:

east rand - i am considering now looking at the power store for stock. it really is a battle to get decent service it seems anywhere

https://www.inverter-warehouse.co.za/ Bought all my panels there.... its less than 2k for the panels you want. Service was great. Oh, and it is close to Edenvale so east rand is no problem. PM me if you want some contact details. 

 

Edited March 23, 20196 yr by stoic

15 hours ago, stoic said:

https://www.inverter-warehouse.co.za/ Bought all my panels there.... its less than 2k for the panels you want. Service was great. Oh, and it is close to Edenvale so east rand is no problem. PM me if you want some contact details.

so the panels are at least 2K each... im guessing the equipment on the DC side will cost around R10k, i have tried them but you just get no response...even on direct email

Edited March 24, 20196 yr by Dex_