Small DIY or plug n play ( Australia)

[Tim Tim]

Tim
Thanks … I’ll look into the giandel
How about the lifepo4 batteries… if I got one 200ah … where do you suggest in aust?
I’m thinking to go w the smaller system and use the generator when running the larger loads..washing machine , vacuum etc.
The generator will need the occasional once a week run anyway
So you’d suggest just go 12v into a good inverter. (3000w)?

Many will say don’t go 12v with a 3000W but the reality is how much power do you want to draw at any one time. You always make allowances for inefficiencies and that is why I bought a 3000W inverter. The biggest appliance I have run is a 2400W kettle which takes a few minutes and did not reach that level of power draw and if I recall it was 199A @ 12v. My two batteries both have a 250A BMS, which is way over the top, and i upgraded my cables to my inverter as the ones that come with them are always light on. You would have no issues running a 1400W washing machine on a sunny day.

 

[Iristocratmusic]

It's just a matter of ensuring your cable is of sufficient gauge.

Cable Size Calculator AS/NZS 3008

Cable size calculator for current rating, voltage drop, loop impedance, earth cable and short circuit, based on Australia and New Zealand standard AS/NZS 3008.

www.jcalc.net

You want to avoid too much voltage drop. With 230 V AC wire doesn't need to be super thick but it will depend on how much current you expect to pump through it.

And importantly, if you ever expect to upgrade the electrical current that cable may need to carry in future then keep that in mind.

Burying cable is a PITA, so better to get it capable of meeting current and future needs. And while you are at it, lay a data cable as well in the same trench (it can be at 200 mm while the power line needs to be at 600 mm deep).

With my system I started with a smaller inverter and my 20 A connections and wire were ample. But eventually I doubled the size of my system and needed to upgrade to 32 A. Fortunately no buried cable for me, but still, new wire and power inlets and outlets.

Thanks…
(I posted this below too after writing this)
I have been seeing several smaller inverters for sale … 2nd hand. A cheaper 2200w giandel $200A ( retails for $300)and a brand called projecta ($300A) 1800w that retails for about $1000. I think these are Australian made.
Both are 12v pure sine wave inverters.
Any comments on which way to go…
Or is it better to get All in one unit?

 

[Iristocratmusic]

Many will say don’t go 12v with a 3000W but the reality is how much power do you want to draw at any one time. You always make allowances for inefficiencies and that is why I bought a 3000W inverter. The biggest appliance I have run is a 2400W kettle which takes a few minutes and did not reach that level of power draw and if I recall it was 199A @ 12v. My two batteries both have a 250A BMS, which is way over the top, and i upgraded my cables to my inverter as the ones that come with them are always light on. You would have no issues running a 1400W washing machine on a sunny day.

Thanks… re inverters… and I’m putting this to the forum too…I have been seeing several smaller inverters for sale … 2nd hand. A cheaper 2200w giandel $200A ( retails for $300)and a brand called projecta ($300A) 1800w that retails for about $1000. I think these are Australian made.
Both are 12v pure sine wave inverters.
Any comments on which way to go…
Or is it better to get All in one unit?
Now reading your post…Or wait to find a good 3000w pure sine inverter
To ensure I have enough power for occasional larger loads…that makes sense

 

[Iristocratmusic]

Calculating my load via the unbound website
(Without large loads)
I got 1780w per day
53 kw p month
And system .51Kw
Does that sounds right for a small system.?

Inverter:
Is a 12v system fine for this?
3000m pure sine inverter ( brand suggestions)
1 x 200Ah lifepo4
Solar regulator ( suggestions)

Do I need a 24v inverter if I go 24v system?
Can a 12v inverter work in a 24v system?
Most 2nd hand inverters are 12v but probably because they’re out of van/ 4wd set ups?

 

[Iristocratmusic]

If I were to be buying a LiFePO4 battery then Aussie batteries would be my choice but I have built my own by buying 280Ah cells and a BMS from from China.

Amy has a good reputation although you do pay a little more but you can also buy your BMS from her which saves on postage costs.

https://szluyuan.en.alibaba.com/pro...?spm=a2700.shop_index.111720.3.7db6273eOKcQh4

https://www.alibaba.com/product-det...html?spm=a2700.shop_index.84.6.7db6273eOKcQh4

Good luck
Tim

You linked Aussie batteries earlier is this Amy ?
I haven’t looked into the cells but I know will has some stuff on this… you join them together…?
And what is the BMS? This is bought seperately?

 

[wattmatters]

I got 1780w per day

Do you mean 1780 Wh per day?

W and Wh are very different.

Assuming you mean Wh, then as 12 V system will manage that easily.

I think if you wanted to run the other high power stuff with an inverter then you might be better to consider a 48 V system.

I make no comment on the inverter options, I don't know much about those 12 V inverters.

 

[Rednecktek]

Calculating my load via the unbound website
(Without large loads)
I got 1780w per day
53 kw p month
And system .51Kw
Does that sounds right for a small system.?

Not unreasonable at all.

Inverter:
Is a 12v system fine for this?
3000m pure sine inverter ( brand suggestions)
1 x 200Ah lifepo4
Solar regulator ( suggestions)

100ah BMS will limit you to 1200w of inverter, 200a BMS will limit you to 2400w. To feed a 3kw inverter on 12v you're looking at a minimum of 3 batteries in parallel to feed it.

Do I need a 24v inverter if I go 24v system?
Can a 12v inverter work in a 24v system?
Most 2nd hand inverters are 12v but probably because they’re out of van/ 4wd set ups?

An inverter must be matched to the nominal voltage of the batteries so if you're on a 12v system you MUST use a 12v inverter, likewise a 24v inverter can ONLY be used with a 24v battery system. 12v will not run and just shut off on low voltage and a 48v battery will release the magic orange smoke.

 

[Tim Tim]

I do have 1700w selectronic sine wave inverter and a decent solar charge controller from the old system I could re commission. Then I can focus funds on a couple of quality lifepo4 batteries.
These units are about 15 yrs old though … so I May need to beef up my budget and buy some new gear like victron. What do you think?

Sry but I just saw the photos of your existing system. If it is just the batteries that have failed then why don’t you just replace the AGM’s plus add a few extras. Is that a 12v or 24v system that is currently installed? The system will probably run your washing machine, and probably your vacuum depending on the wattage but you could use your generator if need be in any case.

If you were to change over to LiFePO4 batteries then in all probability you would need to change your solar controller unless your current model one is compatible.

I have both Epever and Victron solar controllers.

Amy is the Alibaba link to buying cells from China. If buying cells you also need a battery management system (BMS). All LiFePO4 batteries have one inside. If you want to set up quickly and without lots of works I suggest you look at the Aussiebatteries link I posted. It then comes down to whether you want a AGM’s or LiFePO4, the latter meaning an upgrade of the solar controller, and whether you really need to go to a 24v system. Personally I wouldn’t bother with the loads you are drawing for limited time.

 

[Iristocratmusic]

Sry but I just saw the photos of your existing system. If it is just the batteries that have failed then why don’t you just replace the AGM’s plus add a few extras. Is that a 12v or 24v system that is currently installed? The system will probably run your washing machine, and probably your vacuum depending on the wattage but you could use your generator if need be in any case.

If you were to change over to LiFePO4 batteries then in all probability you would need to change your solar controller unless your current model one is compatible.

I have both Epever and Victron solar controllers.

Amy is the Alibaba link to buying cells from China. If buying cells you also need a battery management system (BMS). All LiFePO4 batteries have one inside. If you want to set up quickly and without lots of works I suggest you look at the Aussiebatteries link I posted. It then comes down to whether you want a AGM’s or LiFePO4, the latter meaning an upgrade of the solar controller, and whether you really need to go to a 24v system. Personally I wouldn’t bother with the loads you are drawing for limited time.

Hi
Yes I have looked a little at this… going to test the solar panels this weekend. The system is 24v.. I have thought to do as u suggest…change to lifepo4…and change solar charger or see if it’s useable. I spoke to selectonic about the inverter…def 24 v… so I need a 24v battery…apparently power plus in Melbourne sell 24v batteries . Any other ideas welcome .
As we’re not there all the time …I’m hesitant to spend too much … maybe build a small system for light loads … till we decide if we will live there .

 

[Iristocratmusic]

Not unreasonable at all.

100ah BMS will limit you to 1200w of inverter, 200a BMS will limit you to 2400w. To feed a 3kw inverter on 12v you're looking at a minimum of 3 batteries in parallel to feed it.

An inverter must be matched to the nominal voltage of the batteries so if you're on a 12v system you MUST use a 12v inverter, likewise a 24v inverter can ONLY be used with a 24v battery system. 12v will not run and just shut off on low voltage and a 48v battery will release the magic orange smoke.

Thanks…good info. I’m checking the pv panels this weekend. Will post pics and results .

 

[Iristocratmusic]

Do you mean 1780 Wh per day?

W and Wh are very different.

Assuming you mean Wh, then as 12 V system will manage that easily.

I think if you wanted to run the other high power stuff with an inverter then you might be better to consider a 48 V system.

I make no comment on the inverter options, I don't know much about those 12 V inverters.

Watts and watt hours…
The 1780 wh (?) from an online page… but I’ll
Check the unit of measurement again. It was light loads batteries / house lights/ ceiling fans… and considering days of poor/ no sun.