Noob from Harare checking in

[Boombastic]

Hi everyone!

Zim is going through some serious loadshedding .  Off at 4am and back at 10pm every day.  So I have decided to go the solar route.  For the past 2 months I have been reading up on solar whenever I can.  I have engaged with over 15 solar suppliers in Harare, some established and some not so.  And yes, in case any of you are wondering, those stolen Leoch batteries featured on Carte Blanche have landed up here.  I've seen them with my own eyes and reported it to Averge Technologies (got to do the right thing init?).

About 6 years ago I put up a Microtek 24v 1500Va inverter and 2 lead acid deep cycle batteries.  I had it connected to power only my lights, a few plug points in the bedrooms, TV, decoder, laptop and PC.  With the onset of load shedding, the 6 hours of power we did get in a 24 hour cycle wasn't enough to charge my batteries to full.  They ran flat and hence, permanently damaged.

I purchased 4 Suntech 325W solar panels along with a 40A MPPT controller, 6mm solar cable, the Unistrut rails, brackets and anti-theft clips.  I had a reputable company come and put up the panels and connect everything up but am very unhappy with their shoddy job hence posting to the forum and wanting to sort it myself.  I have a few of questions:

• I am aware that the panels have to be connected in parallel.  Youtubing here and there and found you should only connect 2 panels in parallel using MC4 connectors.  Is this true or can I connect all 4 of my panels using MC4 branch connectors?  The installers shaved the insulation off the cable to expose the bare wire underneath and joined them up and taped them together.  And I know this is wrong .
• Should there be a space between the panels to allow for expansion of the panels?
• If yes to the previous question, where might I find the mid-clamp brackets (spring nuts come to mind)?  The installers didn't put any end-clamp brackets either.  It's not a problem for me to source these items from South Africa.
• I have a 41x41 slotted Unistrut rail (C- or U- rail) and the ARaymond PowAR Snap S anti-theft clips fitted to the panel and rail but they are sliding up and down the rail.  With the mid- and end-clamps, what kind of screw may I use?  All this is to prevent theft or make it difficult to remove.
• I have the brackets but they weren't screwed into the roof beams so what kind of screw may I use to fasten them to the beams?
• The rail came in a 6m length but was cut in 2 for ease of transport.  Where might I find a splice kit (U bracket) for it?

I have more questons but this should be enough to start me off.  Thank you all for your help.

Edited August 20, 2019 by Boombastic

[Guest]

Welcome @Boombastic

@Jaco de Jongh would be the best person to answer.

What I did, and I can go 4 in series, 5 parallel, was a combiner box like so - today only 2 series and 5 parallel. 

[Jaco De Jongh]

6 hours ago, Boombastic said:

Should there be a space between the panels to allow for expansion of the panels?

Hi the space is normally created by your mid clamps. 

6 hours ago, Boombastic said:

If yes to the previous question, where might I find the mid-clamp brackets (spring nuts come to mind)?  The installers didn't put any end-clamp brackets either.  It's not a problem for me to source these items from South Africa.

When i was still using uni-strut for my mounting rails i bought these from GC solar in Centurion (Pretoria) These are designed specifically for uni-strut. They are fairly cheap. 

 

[Jaco De Jongh]

6 hours ago, Boombastic said:

With the mid- and end-clamps, what kind of screw may I use?  All this is to prevent theft or make it difficult to remove.

I have used similar to these 2 before, you will need a M8 x50. 

With the first type you will shear off the head after you have tightened it, making it almost impossible to remove, with the other one you get a special tool to fit the head so that you can remove it later should you need to. 

6 hours ago, Boombastic said:

The rail came in a 6m length but was cut in 2 for ease of transport.  Where might I find a splice kit (U bracket) for it?

In the picture in my fist post you will see a plate, its not the correct one but it will give you an idea. In my installations I joined the rails with a plate double that lenth with 4 holes. 

I would put the end of the rails together, then put the plate into the rail at the bottom with 2 holes in one rail and 2 holes in the other. I would then put bolts through to hold them together, This works fine if the joint it in the middle somewhere, but not that good on a joint close to the end of the rail. 

6 hours ago, Boombastic said:

I have the brackets but they weren't screwed into the roof beams so what kind of screw may I use to fasten them to the beams?

I currently use they and they are great.

 

[Jaco De Jongh]

17 hours ago, Boombastic said:

I am aware that the panels have to be connected in parallel.  Youtubing here and there and found you should only connect 2 panels in parallel using MC4 connectors.  Is this true or can I connect all 4 of my panels using MC4 branch connectors?  The installers shaved the insulation off the cable to expose the bare wire underneath and joined them up and taped them together.  And I know this is wrong .

The correct way is to take 2 wires from each panel/string to a combiner box as @The Terrible Triplett has pointed out above. In the combiner you will typically have a fuse for all the strings, a surge arrested and an isolator. Having multiple strings connected together like yours isn't good and might create some issues should one panel short out. 

[___]

I now have this song stuck in my head...

 

[Guest]

11 hours ago, Jaco de Jongh said:

... combiner you will typically have a fuse for all the strings, a surge arrested and an isolator.

Interestingly thing I learnt recently and also why I don't have fuses is that if you use, as in my case, 16amp NoArk breakers on each string, they serve two purposes:
1) each NoArk being a isolator per string - so I can test each strings production by flicking a few breakers.
2) and you don't need fuses - I quote, after translation: Fuses are there to respond quick on over currents. NoArk does the same, just maybe a bit slower.

But ok, 1 breaker and 5 fuses is cheaper than 5 x breakers.

Bar the testing convenience, I also planned for potential future Eskom woes OR if ever we get paid to feed back.

To this effect, the same combiner box can go double i.e. from 3.5kw to 7kw by going from 2S / 5P to 4S / 5P seeing that the amps will stay the same, just the volts will increase.

Note: To go 7kw I need a 48v inverter and a 250/100 MPPT with either a huge big battery bank OR being paid to feed back to the grid.

[Jaco De Jongh]

4 minutes ago, The Terrible Triplett said:

Interestingly thing I learnt recently and also why I don't have fuses is that if you use, as in my case, 16amp NoArk breakers on each string, they serve two purposes:

I do that if the clients are willing to pay the price. No-Arks increases the price by 40% per string. 

[Guest]

2 minutes ago, Jaco de Jongh said:

I do that if the clients are willing to pay the price. No-Arks increases the price by 40% per string. 

Jip. But I would not say per string but more succinctly that a NoArk breaker is wot, 40% (?) more expensive than a fuse holder and a fuse?
And if you fuse both Pos and Neg sides of each string AND you use those cool fuse holders with that LED in them, that the price difference then becomes less than the 40% difference between a fuse holder and fuse and a double pole breaker.

But rightfully said, it all depends on where you want to spend your monies.

Me, I have paid for a combiner box and then had to redo it when I wanted more panels.
Now I have a spare small combiner boxie lying in a cupboard and the wife is eyeing my cupboard, MY cupboard ... I tell you. 
And I have a bunch of 63amp NoArk breakers also lying around ... in MY cupboard ... 

[Jaco De Jongh]

2 minutes ago, The Terrible Triplett said:

And if you fuse both Pos and Neg sides of each string

That costing was done on a 1000 VDC double pole fuse holder with 1000VDC fuses on + & -., then the fuseholder and fuses is 60% of a No-Arks price.  

[Jaco De Jongh]

4 minutes ago, The Terrible Triplett said:

in MY cupboard ... 

And they can put up a great fight trying to convince you it was their cupboard to start off with....  my understanding was so much different when I bought the house, but let me rather keep quiet.....

[Guest]

8 minutes ago, Jaco de Jongh said:

That costing was done on a 1000 VDC double pole fuse holder with 1000VDC fuses on + & -., then the fuseholder and fuses is 60% of a No-Arks price.  

Apologies, just did the sums.

The 16amp NoArk's are quite pricey. In my case it was an additional +-R1129 more than the fuses.

 

15 minutes ago, Jaco de Jongh said:

... my understanding was so much different when I bought the house

Ditto. AND less we not mention "they" go back on previous agreements on a whim too!
And when you do capitulate and give back graciously "the cupboard" ... then they don't use it because then they "feel bad". 
Conclusion: MY cupboard. Move along and don't open it if it bothers you. Tata.
(Jip, came very close to visiting the ER that day ... and she is half my size and blond but dang, don't mess with her!)

[Riaanh]

On 2019/08/20 at 3:04 PM, Boombastic said:

And yes, in case any of you are wondering, those stolen Leoch batteries featured on Carte Blanche have landed up here.  I've seen them with my own eyes and reported it to Averge Technologies (got to do the right thing init?).

Just when they though with Carte Blanche expose, no one will touch these, maybe only in SA, the thieves just expand their market.

https://rekordcenturion.co.za/lnn/776752/crime-syndicates-steal-mobile-service-providers-blind/

[Dougiedanger]

They have been finding a ready market in Zim for awhile now, also seeing plenty of the Narada 200ah batteries which I believe are also ex Telcom units. 

[Riaanh]

20 minutes ago, Dougiedanger said:

They have been finding a ready market in Zim for awhile now, also seeing plenty of the Narada 200ah batteries which I believe are also ex Telcom units. 

Correct, one can even in the image in the article see the Leoch's in front (Black) and the Narada's (White) in the background.

I don't think there is an easy solution to put an end to this

[Guest]

57 minutes ago, Riaanh said:

I don't think there is an easy solution to put an end to this

I agree with you.

What I hope to see is that they don't replace the batts so when power is off, no-one has cell signal.
So then the people get upset right?
Now the cell Co's reply by standing together and keep on pointing out these thefts in the media, over and over.
End result? The people around these towers start keeping an eye on the equipment.

Because to keep on replacing increases the costs of cell connectivity inexorably.
You cannot protect the batts at all. No structure will keep the thieves out.
You cannot put security on all the sites.
So make it a community problem. If that does not work, well, then tough when Eskom goes off.