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Reducing consumption of electricity by changing to gas cooking makes no sense unless we're looking at 100% off-grid set-up with no Eskom supply. Firstly, you incur capital expenditure setting it all u

They are there to protect the cable and limit the possibility of a fire. I have a solar fuse on each string (12A). If you have a short on one of your strings it will "draw current from the remaining s

Some of the most important things to keep in mind when selecting fuses to be used for PV lines and in line with the batteries - taken from http://www.littelfuse.com/~/media/electronics/product_catalog

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Hi All.,

Hope well. Some Members will be uploading some guides to the Downloads section of the forum.

These guides are tips and tricks they have learned in the trade. It also serves as allowing the new members who wish to get started to make informed decisions and learn from successes of other members. Everyone is free to contribute no matter how small or big.

Sincerely

Jason

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Just now, Energy said:

Hi All.,

Hope well. Some Members will be uploading some guides to the Downloads section of the forum.

These guides are tips and tricks they have learned in the trade. It also serves as allowing the new members who wish to get started to make informed decisions and learn from successes of other members. Everyone is free to contribute no matter how small or big.

Sincerely

Jason

May I add that members that upload usefull guides and tips, Will earn "Units" the forums currency.

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  • 4 weeks later...

Good day to all, I am newbie with solar and is building a new house and will be going as green as I can...;)

I would like to know if this solar setup would be correct?

The daily consumption will be around 3800Wh. 

I want to use a  Axpert 5000VA/4000W Inverter Charger, 8 x 260W / poly solar panel (all connected in parallel) and 8 x 12V/260Ah batteries (connected 2 x parallel strings with 4 x batteries in series) .See drawing and data info as attachments.

I am not sure... what will my output be from the inverter using this battery bank, I do realize that there is a lot a factor influencing the hole setup but would it be able to supply the daily consumption (3800Wh)?

OmniPower Battery.pdf

poly_250-260_en.pdf

BROCHURE HOMIV Invertor.pdf

Drawing of setup.png

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Tooi, welcome to the forum.

Your picture is on the right track. Just add a combiner box between Voltronic inverter and panels, and off course all the fuses between panels and controller, batteries and inverter.

Two things I would do if I build a new house today:
1) Have network points in each room - Wifi is obviously what most use, I do not.
2) Next to each Eskom wall socket, I will add a (blue/black/red) socket dedicated for solar / inverter feed.

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TTT - exactly... I would even maybe consider 12V lighting as an option as well as USB sockets (12V source) for each room for car chargers, etc (instead of cell charges with little transformers inside...

The joys of a new build.  Double gazed windows maybe... etc etc etc

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17 minutes ago, The Terrible Triplett said:

Mark, re. the 12v lighting, how do you overcome the max length from source if it exceeds, wot, 10m?

Haven't thought a lot about it but a thick run in the ceiling (12V conduit) and the thinner cable for the shorter runs...

Otherwise just a bigger inverter and stay with 230V... its going to be free anyway.

Must say - OFF GRID is the way to go... spend the money now and don't bother with municipal connection!!

 

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13 hours ago, Tooi said:

Good day to all, I am newbie with solar and is building a new house and will be going as green as I can...;)

I would like to know if this solar setup would be correct?

The daily consumption will be around 3800Wh. 

I want to use a  Axpert 5000VA/4000W Inverter Charger, 8 x 260W / poly solar panel (all connected in parallel) and 8 x 12V/260Ah batteries (connected 2 x parallel strings with 4 x batteries in series) .See drawing and data info as attachments.

I am not sure... what will my output be from the inverter using this battery bank, I do realize that there is a lot a factor influencing the hole setup but would it be able to supply the daily consumption (3800Wh)?

OmniPower Battery.pdf

poly_250-260_en.pdf

BROCHURE HOMIV Invertor.pdf

Drawing of setup.png

Run your panels in 4 sets of 3 panels, it tends to be a bit more efficient. 

Use a Solar combiner box with 12A "10x38" fuses

On the battery side a 160A fuse, per battery would be recommended. 
And use surge arrestors, both in the Solar combiner box (Class 2 recommended) and before + after the axpert inverter. Here a Class 1, or Class 2 would be used, depending on your house's surge protection. Generally, if you have a surge / lightning mast, and "pits" on the roof, you would use a Class 1 surge arrestor. 

9 hours ago, The Terrible Triplett said:

Mark, re. the 12v lighting, how do you overcome the max length from source if it exceeds, wot, 10m?

don't run 12V lights in the house ;) It aint worth-it. Copper is too expensive. 

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20 minutes ago, SilverNodashi said:

don't run 12V lights in the house ;) It aint worth-it. Copper is too expensive. 

That was what I thought. Use the 220v existing circuits, much easier and all is already in place, after you have replaced all the bulbs, spotlights and tubes with LED's. 

Tooi, I had a double pole switch installed for the lights circuits. Can switch both live and neutral from Eskom to inverter and back if I need to.

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That was what I thought. Use the 220v existing circuits, much easier and all is already in place, after you have replaced all the bulbs, spotlights and tubes with LED's. 

Tooi, I had a double pole switch installed for the lights circuits. Can switch both live and neutral from Eskom to inverter and back if I need to.

Can you explaine a bit more in detail

Sent from my SM-G920F using Tapatalk

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Story behind the switch, where electrician damaged my UPS.

If your system is off-grid like mine, live and / or neutral from inverter, can NEVER mix with live and / or neutral from Eskom. NEVER. First time what they did was they thought that only the live can be switched, leaving the neutral on Eskom. Very bad move.

Way I eventually made the electrician understand, I told him to take light circuit LIVE and NEUTRAL from the DB board, keeping the trips in place, for I want to put a 3 point plug onto them wires. That was the aaah moment.

So now you have live and neutral of the lights in your hand, trips still in place in the DB board on the live wire. Now you can feed them power: Eskom OR Inverter.

I had a similar switch installed. Shore is Eskom, Generator is Inverter.

 

Double pole.jpg

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19 minutes ago, The Terrible Triplett said:

Story behind the switch, where electrician damaged my UPS.

If your system is off-grid like mine, live and / or neutral from inverter, can NEVER mix with live and / or neutral from Eskom. NEVER. First time what they did was they thought that only the live can be switched, leaving the neutral on Eskom. Very bad move.

Way I eventually made the electrician understand, I told him to take light circuit LIVE and NEUTRAL from the DB board, keeping the trips in place, for I want to put a 3 point plug onto them wires. That was the aaah moment.

So now you have live and neutral of the lights in your hand, trips still in place in the DB board on the live wire. Now you can feed them power: Eskom OR Inverter.

I had a similar switch installed. Shore is Eskom, Generator is Inverter.

 

Double pole.jpg

That's a common change over switch, which is commonly used for generators. Most inverters shouldn't ^need^ this unless you want a backup for when the inverter / batteries / PV needs to be serviced/replaced. 

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Thanks for all the feed back... I really appreciate it and will modify my setup until it all is good on paper before installation (practical never work out as in theory....:))

I asked a lot of friends and had a long thought about the 12v lights but I think the best way out is with  220v - LED lights and gas water heaters/stoves.  

Unfortunately the ridge of the roof is north/south and I do have a slight problem with mounting the panels...but I was thinking to mount it on a bracket and have it track the sun as it will optimize the output of the PV's.... any ideas?

Thanks 

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1 hour ago, Tooi said:

Thanks for all the feed back... I really appreciate it and will modify my setup until it all is good on paper before installation (practical never work out as in theory....:))

I asked a lot of friends and had a long thought about the 12v lights but I think the best way out is with  220v - LED lights and gas water heaters/stoves.  

Unfortunately the ridge of the roof is north/south and I do have a slight problem with mounting the panels...but I was thinking to mount it on a bracket and have it track the sun as it will optimize the output of the PV's.... any ideas?

Thanks 

What would a tracker cost?

My neighbor built himself a sun tracker a few year ago, spend about R70k on it, mounted 9 panels on it, I think it was 250w. Later on he added some more panels on the roof, and then again some more. So I asked him one day if the tracker really made a difference and he said no, the amount of money he spent to gain 20% was too much - it was cheaper to add more panels to deliver the same 20% additional energy. 

On a solar farm with thousands of panels, it might be worth while using one. I've seem some commercial trackers selling for R400k+. For that price I'd rather build a carport facing north at the right angle for my location and add 30% more panels than I think I would use. i.e. on a 10kw installation that would only be 3kw more panels. At R10/watt (good/bad guesstimate) that's only R30k more! Plus about R4k for cabling, MC connectors, etc, mounts, etc. 

On a 5Kw installation you could get away with another 1.5Kw, or probably even 1Kw. 

 

 

w.r.t the 12V lights in the house, you need to use fuses on all the cables, perhaps some "self re settable fuses could work" and use DC cable. And then you have volt drops to worry about. Let's say you have a 5W, 12V LED that's 60m away from the DB board. The LED requires about 0.4A. Using a 2sqmm (mm2) cable you will suffer about 2%V. 

But if you have, for example 6x 5w down lights in your passage, the picture changes quite a bit. Now you need to run a 8sqmm cable, just for these 6 downlights. 

All our rooms have ceiling fans with 4x 3W or 4x 6w LED lights. The fans won't run on 12V so I would have had to modify the fans and run two sets of cables, in two different conduits. 

Normally a house has a single cable from the DB board to feed multiple lights and you can have all of them on at the same time without issues. With DC, if the cable is too thin, it will get hot / overheat and you could burn your house down if the fuses aren't correctly spec'ed. 

 

IMO the amount of work + cost of copper, new conduits, fuses, etc doesn't save much money in a house. Perhaps in a small place like a garage, garden shed, rural dwelling, etc. 

And then you need a good source of decent 12V LED lights - generally this is very limited. 

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On 3/19/2016 at 11:22 AM, SilverNodashi said:

What would a tracker cost?

My neighbor built himself a sun tracker a few year ago, spend about R70k on it, mounted 9 panels on it, I think it was 250w. Later on he added some more panels on the roof, and then again some more. So I asked him one day if the tracker really made a difference and he said no, the amount of money he spent to gain 20% was too much - it was cheaper to add more panels to deliver the same 20% additional energy. 

On a solar farm with thousands of panels, it might be worth while using one. I've seem some commercial trackers selling for R400k+. For that price I'd rather build a carport facing north at the right angle for my location and add 30% more panels than I think I would use. i.e. on a 10kw installation that would only be 3kw more panels. At R10/watt (good/bad guesstimate) that's only R30k more! Plus about R4k for cabling, MC connectors, etc, mounts, etc. 

On a 5Kw installation you could get away with another 1.5Kw, or probably even 1Kw. 

 

 

w.r.t the 12V lights in the house, you need to use fuses on all the cables, perhaps some "self re settable fuses could work" and use DC cable. And then you have volt drops to worry about. Let's say you have a 5W, 12V LED that's 60m away from the DB board. The LED requires about 0.4A. Using a 2sqmm (mm2) cable you will suffer about 2%V. 

But if you have, for example 6x 5w down lights in your passage, the picture changes quite a bit. Now you need to run a 8sqmm cable, just for these 6 downlights. 

All our rooms have ceiling fans with 4x 3W or 4x 6w LED lights. The fans won't run on 12V so I would have had to modify the fans and run two sets of cables, in two different conduits. 

Normally a house has a single cable from the DB board to feed multiple lights and you can have all of them on at the same time without issues. With DC, if the cable is too thin, it will get hot / overheat and you could burn your house down if the fuses aren't correctly spec'ed. 

 

IMO the amount of work + cost of copper, new conduits, fuses, etc doesn't save much money in a house. Perhaps in a small place like a garage, garden shed, rural dwelling, etc. 

And then you need a good source of decent 12V LED lights - generally this is very limited. 

Sorry our internet was down for some time now (offshore), but yes it makes all sense if you take the costs of only getting a few more watts out the PV's. I think I will stick with 220Vac for my lights. 

Thanks 

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