APV

In the user manual of the Axpert SOL-I-AX-8M, the following is stated on page 47: Note: Parallel feature will be disabled when only PV power is available Does this actually mean, that even if I have batteries connected to it and the Utility power is switched off, that I cannot use more than one in parallel? Or does it simply mean that I cannot use the parallel function without both Utility AND batteries? I know from experience that the older 5kW models use the battery leads to share the parallel current and obviously to keep the outputs. Has anyone actually tested this scenario?

Yes, your statement is 100% correct, IF you interrupt the DC from the PV panels under full load. However, in this scenario, the PV panels are disconnected when they are delivering very low power... Nice demonstration though

If you are considering using a Sonoff switch, you will have to change the wiring a bit. I am sure you can do it!!! If you use a Sonoff and a contactor (230VAC coil), it will look as follows: If you prefer to use a relay with 230VAC coil, it would look as follows:

I do not think a Sonoff switch will work, since it only breaks one of the 2 wires. You will still have leakage to earth via the other (unbroken) PV wire. I really think you need to find a device that has a double pole relay built into it so that you can break both wires coming from the solar panels. Alternatively, you can use the Sonoff to control a double pole relay with a 240V coil. That setup will isolate the PV panels completely as well.

If the problem disappears when you disconnect your panels, you need to build an auto-isolator like I designed and posted - that was the only solution that worked for me. It is only applicable to the following situation: <SPAN STYLE='background:dddd00;'> 1. Inverter in bypass mode AND 2. Solar panels are wet. </SPAN> Regards A

Firstly, are you using the model with the very high PV input (up to 450V)? The circuit will only work for these models with PV panels attached. As @Coulomb has mentioned (more than once), the problem can also occur when the battery voltage is too high. Have you taken any measurements when you ran into error 08?

Yes, the large capacity panels (330W+) are all poly crystalline. Mono would be too expensive...

Hallo @charlez Good job! Have you watched it working around 18h15 and 07h15 (depending on the sun)? I especially like the morning startup where the bulb first starts glowing and then the relay kicks in, the bulb goes off and the inverter switches to solar... Your wires exiting the board on the left top side, look a bit thin to me. Remember that the solar panel current flows through all these wires. For 20A, you should use at least 2.5mm². Maybe your wires are that thick and it is just the photo making them look rather thin? Of course the current will only be high when your panels are delivering maximum power, in other words in bright sunlight and the inverter delivering maximum power...

I would suggest that you replace the PV breaker by a PV isolator in any case - it is just good practise. Breaking only 1 wire to the PV panels does not prevent the AC leakage current from flowing from the inverter via the PV panels to earth. The good news is that I believe that my circuit will work for you then.

Is it an isolator (breaking BOTH wires), or breaker (only breaking 1 wire)? You need to completely isolate the panels to prevent Error 08. If you already have an isolator in place, then my circuit is not going to help you, since it only isolates the PV panels. What is very interesting to me, is that your unit keeps on resetting. Mine only did it 3 times and then complete shut down...

Good. So then the circuit should solve your problem. Let me know how it goes...

Hallo @Classna Bypass mode is when the inverter does not run off batteries (or solar), but only from the Utility power....

@Classna You can replace the LD03-16B12 with one of the following: LD10-26B12, or LD20-26B12 The distributors for Mornsun in Australia, are: DLPC Pty Ltd （Australia & New Zealand） Tel: 61 7 3823 4844 FAX: 61 7 3823 4866 E-mail: [email protected] Website: www.dlpc.com.au Fairmont Marketing(Victoria) （AUSTRALIA） Tel: 03 9878 3077 FAX: 03 9878 4522 E-mail: [email protected]

Hallo @Classna I presume you are located in Australia??? Have you experienced the same issues? Error 08 while the inverter is in bypass and it is raining? I found the AC-DC converter on Alibaba as well: https://www.alibaba.com/showroom/ld03-16b12.html?fsb=y&IndexArea=product_en&CatId=&SearchText=ld03-16b12&isGalleryList=G Maybe you can order from them. You can replace it by any AC-DC converter block. The input must be able to handle up to 440V AC (700V DC) and have an output voltage of 12v and a minimum output current of 250mA . The output voltage can be higher, but then you will need to use another relay and Zener diode. So I guess it will be much simpler for you to just stick to the diagram.

Hallo @Classna You can find the relay at Aliexpress at https://www.aliexpress.com/item/32835375697.html?spm=a2g0o.productlist.0.0.e8d73424MccJGE&algo_pvid=7aedc1e2-263b-4d06-af6e-a4b34421831d&algo_expid=7aedc1e2-263b-4d06-af6e-a4b34421831d-23&btsid=0be3743615958382138547685e0790&ws_ab_test=searchweb0_0,searchweb201602_,searchweb201603_ I cannot find the AC-DC converter at Aliexpress though As @charlez has mentioned, it is widely available, e.g. https://www.edgeelectronics.com/ac-dc-converters/ld03-16b12/ I am also uploading the schematic again - the capacitor values were displayed incorrectly!