Leaderboard

Success ! The radio interference is gone. I improved the inductance and added some capacitors. In order to run several turns trough the ferrite core I went to the motor and transformer winding shop to get some 6mm² winding wire. But they don’t have such. We finally agreed on 2mm² wire that I would use in 3 wire bundles. I bought 10m of it (R40). I also went to the electronic shop to buy 4 0.33µF 310V capacitors (R40). I first thought to have one core for each polarity. But then I realized that the 30A PV current could saturate the core and reduce the inductance. So I decided to run both polarities trough the same core. The two magnetic fields would then cancel each other and prevent saturation. I managed to run each polarity 3 times trough the core. Since the core can be opened it is easy to wind each half separately. I separated the polarities with a piece of card board. One challenge was to strip the 12 wire ends of the tough isolation varnish. The outgoing bundles are hold together with shrinking tubes. I tightened the two half cores together with a strong cable tie to prevent a gap between the core halves. The finished winding is shown in picture below. I had many thoughts how to connect capacitors to the 48V M6 terminals. I finally found the solution shown below. I soldered the capacitor leads to 6X22 washers with a 60W soldering iron. The washers are then installed under the M6 nuts of the terminals. The final installation of inductance and capacitors is shown in picture below. The outgoing leads of the inductance are directly wired to the PV input terminals together with the leads of the capacitors. I had to solder little pieces of installation wire to the capacitors leads because the terminals would not clamp the tiny wire of the capacitors. The other ends are crimped to the earth wire.

D'oh! I'm having the senior moment, thanks. Yes, 20 A per pair should be fine. So 2.3 V drop, or around 3% loss. Pretty reasonable.

Ordinary lead acid batteries don't like heavy discharges; 5 kW would be over 100 A, so over 5C for a 100 Ah battery. This will not be good for long life. They would probably provide that power for a few minutes, at the expense of battery life, if the inverter allowed it to (e.g. if there was no AC-in). But likely the battery voltage would sag so much that the inverter-charger (especially without the KettleKomp™ feature of patched firmware) would immediately switch to grid. 200 Ah (of nominally 48 V) is the minimum recommended size for a 5 kVA (especially a 5 kW) inverter.

It's quite possible that heat is a factor, and 12 panels would definitely generate more heat in the solar charge controller than 3 or 4. Also, yours may be 60-cell panels. Those do need to be wired 3S. But 60-cell panels are much less common these days.

No one rushed to answer this one (and me being suspicious) I posted this on another local forum and the Terrible Tripplett responed: Does this mean that even if you are a registered SSEG CoCT cannot buy your excess power due to the national contact they have with Eskom ?? Correct. Until the Constitution is changed, or it is gazetted, no-one but Eksom is allowed to sell power to anyone. If you are grid-tied, and do go the feedback route, you have to netmeter over 1 year, you owe them some, they owe you nothing. That is about to change ... how, we will have to see. My suggestions, and I've emailed them: 1) Bidirectional meter should be free, not costing me R12k+, offset that cost by paying me a lower rated per kw. 2) If I buy the birectional meter, pay me, ex VAT, Eskom rate per kw. 3) Daily connection fee of wot, +-R14 ex vat per day, nada, no, forget it. Keep the R150 ex VAT connection fee to help offset the ongoing grid maintenance costs. Can only hope that: 1) They do consider the above for there are a lot of homes with spare, who can assist at no cost nor risk, to CoCT. 2) We, the small guys, can make a cent or two ... Thing is though, on a 63amp breaker, you are limited to 3.5kw. But if you can power your house, send the spare back to them, and make R10 per day ... that could be cool.

see attached SSEG tariffs for COCT, got this from the city of Cape Town website, not sure if this is the latest tariff sheet for feed in Tariff.pdf

Ask for their Support department 0120301166, based in Centurion

We have some new pictures. ;)) Will post today. J

awesome. Please keep sending pics