Stage 1 assessment.

I did the initial assessment at the guest farm and what a surprise as how thing's are done. The inverters and battery combo was purchased through a reputable solar company but the installation was done by local electrical contractor that i would rather not name.

This farm cater for around 30 to 36 guests at any time with 12 guest cottages no self catering, 3 meals done from kitchen that is gas reliance. Each cottage was initially supplied by a 1000va inverter powered from a 12v 100ah AGM battery installed inside the cottage right next to the main bedroom and the fan never switched off. After many complaints the inverters was moved outside, but still audible in the quiet, tranquil environment. So next step put a label on the inverter to switch it off if noise becomes unbearable. Below pictures i took when staying over and believe me the noise was irritating.

 

 

 

Read the label above🤣

 

Stage 2 the new installation.

4 x 12kw3Ph Sunsynk inverters supplying independently. 3 x inverters servicing the cottages and 1 supplying the dining room. 4 x 20kwh FW in parallel supplying the inverters. 60 x 460w Seraphim Siv Series solar panels connected 15S1P 4 strings(30xNE and 30x NW) each string connected to Mppt1 on each inverter. Each string Voc 622.8V+16%(-20°C)=722.5V.  It appears the  lowest  temperature that has  been recorded  in Southern Africa was  in  one  of the valley's  of Lesotho, just to the west  of the escarpment (near Sani Pass) close to the guest farm hence the reason for such a low offset on solar. 

This time around i used good old fashion cable racks to accommodate the 95mm² battery cables running some length to each inverter.

I used exactly the same solar panels (Seraphim Siv 460wp)in the Checkers CL 33 install as they perform very well.

I occupied their "sort off" board room for the inverters and batteries 😜

Sort of "board room"

 

 

 

 

 

This above distribution was re-done twice hence the labelling "work in progress"

4 curcuits used 2 spare. 

The most difficult and annoying part off this installation was the laying of the 165 meters of 16mm² SWA cable different lengths different directions.😩

 

 

 

This is the new style of installation no airflow!!!!

Edited February 1, 20242 yr by TaliaB

Did they Cement in some BigJim toolboxes?

2 hours ago, PsyWulf said:

Did they Cement in some BigJim toolboxes?

Yep Rawl bolted to the wall

On 2024/02/02 at 8:53 PM, TaliaB said:

Yep Rawl bolted to the wall

Oh...well that's...a creative solution to putting an indoor unit outside I guess

26 minutes ago, PsyWulf said:

Oh...well that's...a creative solution to putting an indoor unit outside I guess

Except the inverter will overheat inside a sealed enclosure and to make it worse it is laying horizontallish.

Edited February 4, 20242 yr by TaliaB

Nice 👌

Would appreciate a few close up pics of the inverters + the cabling. 

Just a question or two, 

1. Why did you'll choose 4 x 12kw opposed to going HV, eg one 50kw inverter? 

2. How do the inverter battery comms work in this case if the inverters are all running independently, are they running on voltage mode with no comms? 

Edited February 4, 20242 yr by abd7

1 hour ago, TaliaB said:

Except the inverter will overheat inside a sealed enclosure and to make it worse it is laying horizontallish.

I didn't say it's a good solution 😆

On 2024/02/01 at 8:11 PM, TaliaB said:

that i would rather not name

Pity some other sucker who ends up using these idiots.  Apart from the outrageously poor design this installation could pose serious fire and electrocution risks.

I am a great believer in "name and shame" where the evidence is so compelling.  One does of course need to stick to indisputable facts when doing so.

7 hours ago, abd7 said:

Would appreciate a few close up pics of the inverters + the cabling. 

I wiil go through my foto gallery and see which close-ups i can post.

7 hours ago, abd7 said:

1. Why did you'll choose 4 x 12kw opposed to going HV, eg one 50kw inverter? 

I did originally advised to install the ATESS system but the Guest farm owner was adamant to have seperate power sources, as i should have mentioned they get a lot of lightning strikes on the farm. The "board room" is almost a Faraday cage as there is four ATS(air terminations installed) with 8(DCS) down conductor systems installed using 25mm² wires to 8 difrrent earth spikes.

 

7 hours ago, abd7 said:

2.How do the inverter battery comms work in this case if the inverters are all running independently, are they running on voltage mode with no comms? 

The batteries One(top left) LiTE is programmed as the Master and the other as slaves. The parallel LiTE’s is connected to each other via the CAN Bus using standard LAN cable. Non Can interface with inverter back to grid 51v inverter utility charger set to 53.5v and the SCC set to 55.8v.

Is there not supposed to be a 10cm gap between the panel and roof or is that just for tiles or is that just hearsay?

Same question, been doing it as high as possible always for airflow and heard or read 150mm gap is needed. However for some mounting systems such as galv roofing and the brackets they maybe 50mm high. I assume the railing companies know the law better in their designs but again the PV industry hoarse bolted before much industry teaching could happen. 

4 hours ago, Lee2 said:

Is there not supposed to be a 10cm gap between the panel and roof or is that just for tiles or is that just hearsay?

@Lee2Good deduction from the foto. Yes normally the air gap between roof and panel should be between 100~110mm. I had a structural engineer consulting on this project as the solar array added 1400kg to the roof structure. After consultation he advised that the roof structure was sound to accommodate the extra weight but he had concerns about the wind load in the geographical area( Winterton). We then decided on the lower mounting that would result in less wind load to the roof.

The reason for the 100mm air gap is for module efficiency but seeing that the average temps in the Drakensberg escarpment is quite moderate the decision was made to go for the lower mounting. 

 

On 2024/02/04 at 9:24 PM, TaliaB said:

The batteries One(top left) LiTE is programmed as the Master and the other as slaves. The parallel LiTE’s is connected to each other via the CAN Bus using standard LAN cable. Non Can interface with inverter back to grid 51v inverter utility charger set to 53.5v and the SCC set to 55.8v.

I'm interested in this due to a an issue I'm having a plant of ours, and am looking at using voltage based control on the inverter rather than BMS comms. 

1. Have you noticed any negatives using voltage control without BMS comms?

2. How are you monitoring the actual battery SoC? 

On 2024/02/04 at 9:24 PM, TaliaB said:

 inverter utility charger set to 53.5v and the SCC set to 55.8v.

Can you also clarify what exactly is meant here, 

As per Sunsynk inverter we have the settings :

Float V

Absorbtion V

Equalisation V

@TaliaB am loving the install, brilliant, well done. Now what happens to regulatory safety eg.:

1. Smoke detector
2. Fire hydrants / retardants - yes am mindful that once thermal runaway begins, really not much can be done, to be honest
3. A maintenance contract by yourself and your team to ensure cables are still intact - heating and cooling of connections can result in some becoming loose over time or if they have a problem with rodents seeking warmth chewing on cables...🤣
4. Cameras with external recording to ensure any vandalism is recorded
5. Signage on to ensure access is restricted to AUTHORISED PERSONS ONLY - BEYOND THIS POINT

There's an install in Nigeria where a staff member became quite unhappy with a new install such as this, having been done, because it meant his days of pilfering fuel for the generator and his revenue from theft were taken away and he began sabotaging the install (hence my idea of cameras).

Edited February 12, 20242 yr by Moffat

Great install. I like the multiple inverters as it gives yiu redundancy, and for that reason I also like 5kw battery stacks.

Top notch work. Many can criticize, few can do