Sophon

I already have the UKK80 terminal blocks, what I am looking for are blanking strips that can block the opening in the DIN box front plate in front of the UKK80 blocks. Like these (for a Schneider box):

Thanks again. I have been searching Lazada/Shopee/AliExpress but have been unable to find anything. Maybe they are there, but unfortunately I don't know what they are officially called. The only thing I can find are "blanks" like these: But they don't work if the spot is already filled with a UKK80 terminal block. Of course, I can make something myself, but it won't look very nice.

Completely unrelated question. Isn't there such a thing as blanking strips/plates for DIN mount CUs? I will have two boxes in the solar installation, but in one of them some of the spots will not be filled or filled with UKK80 terminal blocks that don't fill out the gap in the front plate.

Thanks. Verify with my meter how, by measuring the resistance between panel and supports?

How have you guys grounded your solar panels? My solar panels will be ground mounted and each panel will be attached to the support metal structure (which will be bonded to the ground rod) with 8-10 screws/bolts. Will that be enough grounding, or should I run wires from the panels to the metal support or even to the ground rod?

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Why pay USD 36 for a 200AH battery, when you can get a 280AH battery for USD 20 from the same seller: The seller seems to be genuine and has very good reviews, but there is definitely something funky going on with some of their pricing.

I wonder if the calculator from the European Commission is biased towards colder climates: If we compare the numbers from January and August, I would be producing more than 4 kWh per day more in January than I would in August. That is reflected in the fact that the calculator expects me to fully charge my battery 29 days in January against only 22 days in August. However, the calculator for some reason also expects me to run out of battery every single day in January but only on 21 days in August. That makes no sense to me. The only reason I can think of is that the calculator expects me to use more energy in the winter for heating (it has the battery running out every night in November, December and January), or that it somehow expects that the battery is used for an extended time because of longer nights. That is not really the case in Thailand, where we as a general rule probably use more energy during the night in August (Air condition), and where the difference in day/night hours doesn't wary much from summer to winter. Maybe the calculator has some constants in the calculations that are more relevant for Europe than Thailand. It is after all an calculator supplied by the European Commission. Can anyone come up with a plausible explanation?

Where in Thailand is the Global you use?

Probably sound advice from a financial point of view, but personally it would have no interest to me. If this was just about saving money I wouldn't bother with the project, the savings wouldn't be that substantial anyway. The primary purpose isn't saving money, I just like the idea of being (mostly) independent from the grid, and not being in the dark when the grid is down. Of course, I don't like the idea of burning money so installing solar has to make at least some kind of financial sense. I am happy if I can achieve savings in the region of 10% annually of the initially invested amount.

If I end up going with the 390W BlueTech panels, it won't be to save money. The panels would actually be more expensive, both per watt and in total, than the option from Global. But I would get a better panel (mono crystalline and half cut), and that would be worth the extra money to me. What's holding me back is the risk of having to deal with panels broken in transport, so if I could find a brick and mortar shop selling this panel for a comparable price, I would definitely go pick them up myself. I have been scouring the internet, but haven't been able to find any solar shops in the Chiang Mai region. Lots of companies doing big projects, but none that just sell the equipment. So if someone knows of a shop in or around Chiang Mai with a good selection of solar panels (and other equipment), I would definitely go check it out.

Having decided to go ahead with the project, I have started ordering some of the smaller stuff from AliExpress. The solar system will be located on one of the wetter parts of our land, so building the structure for the panels will not be done until we are into the dry season - so sometime in October/November depending on the weather. But as we know, deliveries from AliExpress can sometime take a couple of months or more. As we still have 2-3 months to go, I will be spending the next few months looking for good prices on the PV panels, Inverter and batteries and pounce if I see a deal I like. I was considering if I should buy the JinYuan panels from Global while they are on sale until the end of this month): I can't find a spec sheet for this panel on the web, the closest I got was specs from JinYuan's own website for the panel series JYXXXP72, but that only covers the 320W, 325W and 330W models. According to Global: Voc: ? Vmp: 38.2V Imp: 8.94A According to seller on Alibaba (and his information correlates with the JinYuan spec sheet for 320W, 325W and 330W): Voc: 47.1V Vmp: 38.7V Imp: 8.79A Price per Watt: 3,490 Baht/340W = 10.26 Baht/W I would buy 12 panels for a total cost of 41,880 Baht for 4,080W of panels. I would have to arrange the panels in two strings of six panels (S6P2 configuration), as 12 panels in series would total Voc of 565V, more than the maximum PV array open circuit voltage rating of the inverters I am looking at (max. 500V). The combined Vmp of the panels in series of 458V/464V (depending on who you trust) would also exceed the MPPT's voltage range of 120-450V. I have also been looking at this panel: From the spec sheet: Voc: 46.2V Vmp: 38.2V Imp: 8.90A The Vmp/Imp doesn't quite add up with it being a 345W panel (comes out to 340W), but using the 345W figure the price per Watt would be: 3,700 Baht (210 Baht shipping)/345W = 10.72 Baht/W Again, I would buy 12 panels for a total cost of 44,400 Baht for 4,140W of panels. Like with the JinYuan panels, I would have to arrange them in a 6S2P configuration to avoid exceeding the inverters maximum open PV array open circuit voltage and stay within the MPPT voltage range. The third and final panel, I am currently considering, is this one: From the spec sheet: Voc: 49.3V Vmp: 41.1V Imp: 9.49A Price per Watt: 4,400 Baht (210 Baht shipping)/390W = 11.28 Baht/W. If I go for this panel, I will buy either 10 or 12 panels for a total cost of: 10 panels: 44,000 Baht for 3,900W of panels. 12 panels: 52,800 Baht for 4.680W of panels. Like before, 12 panels would have to be in a 6S2P configuration, but 10 panels could theoretically be connected in series. The total Voc of the string of 493V would be awfully close to the inverters maximum PV array open circuit voltage rating of 500V, though. To err on the side of caution I think I would go with a 5S2P configuration. The producers of these panels Jinko (JinYuan) and Risen (BlueTech) are both major producers of solar panels, so I would expect that the quality of the panels would be more or less on par. The JinYuan panels is the cheapest option, but for only 10% more per watt I am very tempted to go for the 390W BlueTech panels. With them being Mono crystalline and half-cut, they should supposedly perform a little better under low light, very hot and partially shaded conditions. It also gives me the flexibility to start with 10 panels with only a 200W decrease in total power of the array, and then later add two more if needed. On the flip side, I do like the idea of inspecting the panels when I buy them and taking them home myself, which buying at Global offers. That way you don't have to deal with panels broken in transport or the seller sending the wrong items. And should a panel be defective, Global is very good at taking products back and refunding you. What to do, what to do, what to do.... What would you do?

In theory a 5.5kW inverter should process a maximum of 24A on the AC side, and even if it allows a 10% overload that would only bring the max. to about 26A. So 6 sq.mm in/out wires should be plenty on the AC side. However, if the inverter really just shifts to bypass mode in case of an overload, that would mean that the AC in/out wires could theoretically be exposed to currents of up to 50A, at which point the 50A breaker on the incoming supply from PEA would cut out. So since I have 16 sq.mm. wires left over from when we built the house, I think that I will run 16 sq.mm. the whole way from incoming supply to the inverter, and out from the inverter to the wires for the house (assuming the ports in the inverter can handle the size). Is my reasoning sound, or am I missing something?

I was leaning towards the Y connector. The extra 10cm of wire or so might mean that the wires from the two strings could reach without having to extend one or both of them.

So if you have two strings of PV panels that you want to connect in parallel, which of these connectors would you use?:

It is after 45 days, i.e. during the last 45 days of his 90 day permission to stay.

I saw a video on YouTube from a guy who had done just that. The conclusion was that the East and West facing panels did produce a little more in the morning/evening than the south facing ones. however, because the sunlight is not strong at that time of day, the extra production early morning/late afternoon far from outweighed the reduced production from the panels during the middle portion of the day. He had better results when turning the panels from East and West to instead pointing South-East and South-West, but even so he didn't increase his total production, he just had a little more power early and late in the day (which was his goal). This was a guy living somewhere in the U.S. with snowy winters, so the results could possibly be different in Thailand. but I think the overall principle stays the same. You get the best production from a stationary panel if it points due South.

That's a good price for the panels, were they the BQ Solartech from your local shop you talked about?

There are about 30 different settings, but I have only included the ones that are different between the older and the newer model. It's true that there is not a specific option to select Lithium battery, but the user manual for the newer inverter does say this under features: And under the battery type setting you would then select "User-defined": Since there is not specific Lithium battery setting, this might require you to adjust settings 26, 27 and 29 in order to optimize battery management, but I am hoping that maybe the changes to default settings they have made are partly to address this: For those with inverters with specific Lithium battery settings, what are the values in your inverter for bulk charging voltage, floating charging voltage and low DC cut-off voltage?

So, on to the other changes mainly in the settings and information display software. As I mentioned, the overall impression is that the manufacturer has tried to simplify things by removing settings/options that you would not want to use anyway. Feature 2019 model 2022 model Verdict (IMO) Physical differences: USB communication port Yes No Advantage old model. I don’t know if this is helpful in real life or not. Battery connection Screw connector Ring terminal connector Advantage new model. I imagine a ring terminal connection is more secure. On/Off switch On the side On the bottom Advantage old model. Purely objective, but I prefer the on/off switch to be away from all the wire connections. Inverter settings: Output source priority UTI (utility) mode No UTI mode Neutral. While it can be argued that having more options is always good, I don’t see ever wanting to use a UTI mode. Power saving mode N/A If no or small load the output of the inverter will be off Neutral. I don’t see the point and wouldn’t turn it on Output voltage 220V/230V/240V N/A Neutral. I wouldn’t want to change from the default 230V Charger source priority CUT (utility first) mode No CUT mode Neutral. I would never set the inverter to charge from PEA as first priority Record fault code Enabled as default Disabled as default Neutral. I can just change the setting Low DC cut-off voltage Default 40V Default 42V No opinion. I have no idea which is better, but it can be changed. Battery equalization Enable/disable plus many sub-menus N/A Neutral. As I understand this, it’s only relevant to lead-acid batteries Information screens: PV current Screen shows PV current N/A Advantage old model. Could be useful information. PV power Screen shows PV power N/A Advantage old model. Could be useful information. Charging current Screen shows charging current for utility + PVs with diagrams that show if it’s utility or PV charging. Shows only total MPPT charging current. Only one diagram. Neutral. I wouldn’t charge from utility anyway. Charging power Same as for charging current Same as for charging current Neutral. Load in watt Screen shows Load plus Battery voltage Shows Load plus Input voltage Neutral. The added information is available elsewhere. Battery voltage plus output voltage Screen shows these values N/A Neutral. These values are already available in (several) other screens. The newer model is a little more expensive, but not enough that it would be a deciding factor. I am leaning towards the newer model, mainly because I get the impression that the manufacturer has made an effort to improve battery management. But I would appreciate input from anyone that actually understands what the changes to the DC cut-off and warning values have actually achieved, and whether the changes are an improvement or not. As mentioned earlier, I would like to believe that the changes are a step in the right direction (why else would they do them), but who knows. So for anyone who have actually made it through both this and my previous post, would you go for the older or the newer model? Edit: I see that the formatting of the table came out a bit wonky, but at least it's readable.

So I have decided against going for the Powland hybrid On/Off-grid inverter I posted about on the 12th of August. It turned out, that the second manual the seller sent me was for another inverter, and the manual for the Powland inverter is just lacking in details. There is nothing about the different settings, and being new to solar inverters, I don't want to have to guess what the different options in the settings do. The two Inverters I have narrowed it down to (at least for now), are both cheap Chinese hybrid off-grid inverters. Inverter number one: Inverter number two: The two inverters are basically 95% identical, just different model years with minor updates. The first one (which I believe is the one BritManToo has) is the 2019 model and the second one is the 2022 model. It seems like they have tried to simplify things in the 2022 model, so they have removed settings and information screens, that doesn't necessarily make sense. They have also tried to optimize battery charging (at least that my interpretation of the changes), maybe to make it more compatible with Lithium batteries. Neither model has an option to select Lithium in battery type, but where the older model never mentions Lithium batteries the newer one at least states that it will work with that battery type. In the following I will go through the differences between the two models. The older model is on the left and the newer on the right: The only difference is under the "Output Short Circuit Protection: The new inverter is slightly more efficient. There are also changes to the DC warning and cut-off voltages. I have no way near enough knowledge to determine if these changes are an improvement or not, but one would like to think, that when they make the effort to change things it's for the better. They have added some additional information for the new model, but the only real change is that max. PV charging current has gone up from 100A to 110A. The newer model is a little bigger and heavier, and can apparently work under slightly hotter conditions. So all in all fairly minor changes in the spec. sheets between the two models. Beyond what is mentioned in the specs. there are a few other noteworthy physical changes and quite a few software changes between the two models. But as this post is already quite long, I think I will split those into a separate post. Ignore the below pics. I am unable to delete them.

Our load going over 5.5kW is an unlikely event, but it could theoretically happen in the winter when the water is cold (we live in the north), and if other major loads like a rice cooker is on at the same as we crank up the temperature on the shower heater. At the moment our total load, including all the normal background loads, is around 3.5kW when the shower heater is on. But it will go up somewhat when the water gets colder.. It's definitely not something that would be worth upgrading the system over, if it turns out to be a problem, we will just make sure that we don't take warm showers when other big loads are running. I am just trying to understand, what will happen if we do go over the rated power. The inverter in question has this setting: If I change that to "Bypass enable", would that mean that the inverter would automatically change to PEA power if overloaded, and would it automatically return to normal mode when the load falls below the rated limit?

When it says this in the specifications for an inverter; does that mean that the inverter can operate at 110% of rated capacity for reasonable periods? So a 5.5kW inverter could operate at 6kW during, for instance a 15 minutes shower, when both pump and shower heater is on?

Because I don't have your knowledge about electrics, I am the opposite. In order for me to visualize how things should be put together, i need to map out the exact connections. Putting pen to paper (or electrons to display) also helps me think through what equipment I will need and where problems may arise. Producing the diagram also gives me confidence that I have thought about everything, and that I will actually be able to do this myself. I think my biggest challenge will not come when putting everything together, but if/when something suddenly goes wrong six months down the road. Thank you for taking the time to review my plans.