twingall1 Posted August 25, 2020 Posted August 25, 2020 Hi, I have a 2018 Infinisolar E 5.5kw hybrid inverter from VoltaconSolar. And a pylontech us3000 recently added. I have issues connecting this to BMS, Have modbus card in intelligent slot and this is working well with my smart meter. But when i try to connect a BMS box via the serial port and link the pylontech comms (with the correct cross cable and baud rate setting), nothing registers. Could anyone tell me if this is possible to fix this, maybe with a firmware upgrade? Or some other method of connecting to the BMS? currently connected just with battery cables: it works to an extent but has issues with battery not waking up in the morning, and the SolarPower software misreporting SoC and failing to discharge the battery fully. Another issue i have with this inverter is a seeming limit on peak power: Even on a sunny day, the power from PV (2 strings) maxes out at 2100W x2: a max of 4200W for a 5.5kw rated inverter seems too low. I connect one string alone on a sunny day and it gets up to 2500W+ so clearly the inverter is the limiting factor here.. Any advice on this, or should i just accept 4200W as the effective maximum for this model? Quote
twingall1 Posted August 25, 2020 Author Posted August 25, 2020 these are my settings on SolarPower.exe: Any pointers would be greatly appreciated, getting this system to work well/automatically is proving difficult! Quote
francois Posted August 25, 2020 Posted August 25, 2020 (edited) I think the modbus card has different dipswitch settings for smartmeter vs battery comms? Edit: I am not sure of this. Perhaps @Youdacan advise? Edited August 25, 2020 by francois Quote
twingall1 Posted August 26, 2020 Author Posted August 26, 2020 i didn't think i could use modbus card for bms comms, no mention of it in manual: https://voltaconsolar.com/DOWNLOAD-FILES/Modbus/Modbus card II-manual_20150127.pdf Quote
Youda Posted August 26, 2020 Posted August 26, 2020 (edited) @twingall1 Quote I have issues connecting this to BMS, Have modbus card in intelligent slot and this is working well with my smart meter. But when i try to connect a BMS box via the serial port and link the pylontech comms (with the correct cross cable and baud rate setting), nothing registers. There are two cards available: Modbus Card - for the communication with the energy meter BMS Card - for the communication with the Pylontech For a shame, there's just ONE SLOT and none of the two cards is able to provide both functions at once. Quote Could anyone tell me if this is possible to fix this, maybe with a firmware upgrade? Or some other method of connecting to the BMS? Buy a BMS card instead, throw away the meter. OR, if you want to have both functions together, just contact Voltacon support. But from my experience it's not possible. An alternate way would be to ulitize 3rd party solution to communicate with the Pylontech and control the inverter. For example Manie's ICC. ICC does support some InfiniSolar models, but I'm not sure whether InfiniSolar E is supported too. Just ask Manie first. Quote currently connected just with battery cables: it works to an extent but has issues with battery not waking up in the morning, and the SolarPower software misreporting SoC and failing to discharge the battery fully. Yes, incorrect SoC is obvious, same for the incomplete charging. 3rd party monitoring solution will fix this. Just have to warn you about sleeping/waking up the batteries. That "sleep" is in reality an emergency action of BMS. It means that you've discharged your batteries too much and the cells are starting to suffer from low-voltage. Every time you let this, you are gradually killing the batteries. Buy more batteries or switch to the grid much sooner, so the batteries will not be drained every day. Quote Another issue i have with this inverter is a seeming limit on peak power: Even on a sunny day, the power from PV (2 strings) maxes out at 2100W x2: a max of 4200W for a 5.5kw rated inverter seems too low. I connect one string alone on a sunny day and it gets up to 2500W+ so clearly the inverter is the limiting factor here.. Any advice on this, or should i just accept 4200W as the effective maximum for this model? The MPPT of InfiniSolar E can take up to 6500W, but it's built-in battery charging circuit is limited to 2880W. All the remaining power has to go into the AC loads. So, if there's not enough loads, the power output of the inverter will be limited. In order to check this, just connect some more loads and watch the power going from the PV strings. By the way, you've picked the worst model from the whole InfiniSolar line. For example, InfiniSolar 5K Plus (or InfiniSolar 10K 3-phase) is much better. Next time, go for a Victron solution or carefully choose some all-in-one hybrid from the GoodWe product line. Edited August 26, 2020 by Youda twingall1 1 Quote
twingall1 Posted August 26, 2020 Author Posted August 26, 2020 Thanks Youda. Really appreciate it. 2 hours ago, Youda said: There are two cards available: Modbus Card - for the communication with the energy meter BMS Card - for the communication with the Pylontech For a shame, there's just ONE SLOT and none of the two cards is able to provide both functions at once. Am looking at getting this part exchanged by Voltacon for the 5.5kw plus so I can get the bms functionality: Voltacon tech said that the 5.5kw plus can take both cards: one in the slot and one in box form connected to serial port of inverter. If that proves too expensive, will look into ICC subscription. 2 hours ago, Youda said: Yes, incorrect SoC is obvious, same for the incomplete charging. 3rd party monitoring solution will fix this. Just have to warn you about sleeping/waking up the batteries. That "sleep" is in reality an emergency action of BMS. It means that you've discharged your batteries too much and the cells are starting to suffer from low-voltage. Every time you let this, you are gradually killing the batteries. Buy more batteries or switch to the grid much sooner, so the batteries will not be drained every day. Ok, will tweak the start discharge and stop discharge voltages carefully each day to get max battery discharge without causing emergency sleep mode. 2 hours ago, Youda said: The MPPT of InfiniSolar E can take up to 6500W, but it's built-in battery charging circuit is limited to 2880W. All the remaining power has to go into the AC loads. So, if there's not enough loads, the power output of the inverter will be limited. In order to check this, just connect some more loads and watch the power going from the PV strings. Regarding the power to the loads limit. I have had this for a year running without battery and feeding to grid, and all the while never saw pv output power exceeding 4200W. Will test again with max load but I suspect it will not exceed 4200w. If so, what could be limiting this? and am i right it should definitely be higher? Thanks, T Quote
Youda Posted August 26, 2020 Posted August 26, 2020 23 minutes ago, twingall1 said: Regarding the power to the loads limit. I have had this for a year running without battery and feeding to grid, and all the while never saw pv output power exceeding 4200W. Will test again with max load but I suspect it will not exceed 4200w. If so, what could be limiting this? and am i right it should definitely be higher? Grid feed-in is limited to 3500W because of legal requirements of most of the countries. Therefore, the inverter will never push more than 3500W to the grid. Now it depends where you have your loads connected. If you connect some more loads to the AC-OUT side of the inverter, you should be able to get more power from the inverter. Contrary, if all your loads are connected to the AC-IN side of the inverter, they will never use more than 3500W of PV. Especially, if these loads are connected BEFORE the Inverter's energy meter which is a common mistake that I've seen in some other installations. Since your system is grid-tied installation with grid feed-in enabled, I assume that most of your loads are on the grid side (AC-IN). So just check whether they are connected before(wrong) or after the meter (correct). Moving some of the loads to the AC-OUT is the quickest test to see whether you can draw more power from the panels. BTW, you CAN change the limit of 3500W to 5000W for example, but that would be illegal in most countries. Therefore, don't do it please. Quote
twingall1 Posted August 26, 2020 Author Posted August 26, 2020 (edited) Hi, ah i see. So limit of 3500w to grid would tally with pv input power (see image: reading from this display on SolarPower.exe) being max 2100w+2100w? (accounting for losses?) Well at least i know now that it is probably this. Will live with the cap, its only on the most sunny days that it is reached anyway. Thanks, T Edited August 26, 2020 by twingall1 Quote
RikH Posted September 1, 2020 Posted September 1, 2020 On 2020/08/26 at 9:15 AM, Youda said: Next time, go for a Victron solution or carefully choose some all-in-one hybrid from the GoodWe product line. Now what? You have 3 of these (5K, ok..) Voltronic products and you're advising not to buy these, how come? I remember when I ordered my 5K from MPPsolar it was not in stock and they tried to convince me to buy the 5.5. Happy I didn't. Reason: no possibility to parallel them. So far I'm happy with it. Another question Youda, when the inverter is connected with a meter it will try to compensate for consumption on the AC in side as well. Is this only when the inverter is not allowed to push back into the grid? And will it use the battery as well to compensate for the loads on the AC in side? And beyond that, use the battery to feed in to the grid? Curious... Quote
Youda Posted September 1, 2020 Posted September 1, 2020 3 hours ago, RikH said: Now what? You have 3 of these (5K, ok..) Voltronic products and you're advising not to buy these, how come? Yeah, I know that it might sound strange but I'd like to stay objective whenever comes to judging something (or someone). Some other people are not able to criticize a product if they just spent a huge amount of money on it. For example, a Mercedes owner rarely tells you that there's something bad on the car and that if he had a second chance he would go for a Bentley instead. Also, some people are recommending a product just because they don't want to be only ones who's using it. Even if they know that the product is a bit sh*tty. The case with my InfiniSolars is that I'm okay with them. I know how to manage these machines in my setup, I know how to remotely read operational values and execute commands. But there's a lot of drawbacks and painpoints too and it took me a while to found out. Based on the experience that I've made I have to say that for almost every use case there's a better product available. For example, Axpert is much more efficient and way cheaper for the offgrid solutions. GoodWe is more efficient, more compatible, more intelligent as a hybrid. Victron has much bigger scalability, frequent firmware updates and has a complete ecosystem of devices for automation, monitoring and other accessories. So, yes, I'm happy with my inverters too, but if I will build another house in my life, I will choose a different hardware. Not sure what exactly, but at least I know what features I want and what pitfalls to beware of Calvin 1 Quote
Youda Posted September 1, 2020 Posted September 1, 2020 3 hours ago, RikH said: Another question Youda, when the inverter is connected with a meter it will try to compensate for consumption on the AC in side as well. Is this only when the inverter is not allowed to push back into the grid? And will it use the battery as well to compensate for the loads on the AC in side? And beyond that, use the battery to feed in to the grid? Curious... In my opinion, the best hybrid mode is "Grid Tie with Backup II". Eastron meter is needed in order to get this mode to work correctly. In this mode, the inverter blends Grid+PV+battery power together. It allways try to compensate grid to zero: If there's too much PV power, the inverter lowers it's output in order to reach zero export. If there's a huge load on the backup or AC side, the inverter uses PV first, then battery, then the grid. You can also limit the amount of Power (watts) that will be pulled from the battery. If there's a need for more power than this limit, the remaining watts will be pulled from the grid. Logic: If you have some loads connected to the AC IN side of the inverter, these load will benefit from the PV, Battery and the Grid too. Once the grid is down, these load will go down too. They are not backed up. These load can be huge, there's virtually no limit on Amps. Whatever is connected between the grid and the Eastron meter, will NOT benefit from PV, nor from the battery. If you have some loads connected to the AC OUT side of the inverter, these loads will benefit from PV, Battery, Grid. These loads will be backed up even if the grid goes down. These loads have a current limit of approx 21A. For a shame, this mode does not work with NetMetering because it aims at 0 export. If you have an excess power generation, fully charged batteries and small AC loads, the inverter will lower it's output. If you want to use NetMetering, the best mode is "Grid Tie with Backup I" In this mode Eastron meter must NOT be installed. The logic is very same like in the previous mode, but with two exceptions: All the loads in the house will benefit from PV+GRID, no matter where they are connected. If you have excess PV generation, all of it will be fed to the grid. In most of the countries, there's a limit of roughly 3700W set in the inverter's configuration. Feeding the battery to the grid By default, feeding the battery to the grid is disabled in all the modes. However, if you really want to, you can manually tick "allow grid feed-in" + "allow feed-in battery to the grid". Then the inverter will send all the excess PV generation to the grid, up to a defined limit (normally 3700W). And if there's not enough PV, it will discharge the battery to the grid too. Again, up to a total limit of 3700W by default. For a shame, it's not possible to control battery discharge based on the SoC. It simply discharges the battery up to a point where the low-voltage threshold kicks in. RikH 1 Quote
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