We all know that investing in a residential solar system involves a substantial financial commitment. But given the many advantages to moving off the grid, the initial financial investment is more than worthwhile – especially over the long term. However, if the solar PV system you pay for is not well designed or has been sub-optimally installed, this could erode the future cost savings you should be enjoying. 

At SSESA, we were called in to assist a frustrated homeowner who had an existing Solar PV system that was not designed optimally and had been installed without following PV Greencard or SANS10142 requirements. These were the specs of the existing system:

• 8.8kVa Sunsynk Inverter
• 5.12kWh Dyness battery
• 8 x 550w panels (4.4kWp) 

When we inspected the existing system, we found the following faults:

1. Incorrect design
   The system should have contained at least two of the 5.12kWh batteries. This meant that the inverter could overload the single battery when loads exceed 5 kVa (100A).
   
2. Incorrect inverter settings
   The inverter settings did not allow for night-time battery usage. 
   
3. Non-standard cables
   The cables installed from inverter to fuse holders and fuse holders to batteries were only 25mm. These are insufficient as per SANS10142 standards, and severely limit the system when more batteries are added. Non-standard cables can also cause fires and damage to equipment by overloading.
   
4. No warning labels were applied
   This is a regularity and safety compliance offence.
   
5. AC and DC was mixed instead of being separated. 
   
6. The Automatic Transfer Switch (ATS) was burnt out
   This was due to two loose connections in the installers sub-board, which can be seen in the image below:

7. Sub-standard switchgear
   Some of the electrical switchgear was sub-standard to support Solar PV systems.

After our initial analysis, this is how we then upgraded the system:

1. Additional battery
   We installed another Dyness 5.12kWh battery parallel to the existing Dyness 5.12kWh battery, which ensures that the system can now perform with optimal output as well as maximise the battery storage. 
   
2. Reprogrammed settings to ensure optimal energy usage of the entire system.
   
3. Replaced cables
   We replaced all the 25mm cables with 50mm and 35mm cables respectively, ensuring that the system can now handle the loads and is compliant as well as safe for use.
   
4. Applied all necessary warning labels on the trunking and sub-board.
   
5. Separated the AC and DC by running the two separate conductors in separate wire ways.
   
6. Corrected connections and replaced the cover damaged by the burnt conductors (at an additional cost).

When installing an additional battery, we also completed the following:

• Upgraded fuse holders and fuses for the batteries from 120A to 250A.
• Bonded the additional battery to earth: we installed an ethernet cable between the master and slave battery.
• Configured the batteries with the inverter: maximum output is now 180A (rating of inverter) from the existing 100A (maximum of a single battery).

After upgrading the system, we also advised the client that they could in fact add another 4.4kWp of Solar PV array for extra capacity.

In cases where a solar PV system is installed incorrectly, we believe that the original installer should correct the issue. However, for various reasons this is not always the case. While upgrading or reinstalling your system may involve an additional cost, it’s well worth the peace of mind that your residential solar system is safe and efficient, and that it will last for many years to come.

Are you looking to invest in a residential solar system? As this case study shows, it’s important to make sure you always use a reputable installer so that your system is safe to use, works optimally and doesn’t cost you money to fix it down the line. Looking for a quote on a quality residential solar system? Contact us today.