Webbie

Good idea to buy a solar charge controller on it's own and then add your 2 x 300w panels to that input. Controllers are quite cheap and the more solar you can harness the better in low light times. Glad you got it all working.

you have 2 choices option 1 is to buy a battery charger that's at the right voltage for your batteries (ie 52.3V at 25A) and have that running straight from the genny on it's own circuit. This is what i have, a feed in plug that's outside near the genny and a 15A plug inside next to the inverters. The charger plugs into the genny and only turns on when the genny is running. This then charges the battery at up to 25 amps and the inverters can take what ever they need from the battery's as required as they normally would. This also stops the problem of frequency fluctuation coming through to the appliances and destroying them. The second choice is to buy a second inverter that supports your battery and inputting from the genny into that. This however will be running without any BMS connection so have to set your inverter correctly. I did have this setup using my old inverter until the inverter finally died completely. It worked well on the 2 or 3 times i actually required it but if i didn't have it i would have just done option 1 like i now have. Why pay more for something with abilities you don't require and only will use every now and then. This also has to be installed onto a wall and cabled in. Both options are viable. The only draw back is you have to make sure your inverter is not taking more than the amps your putting in through the charger. in my case thou the 25 amps I'm putting in has about 10 amps lost when the hot water is running otherwise most if not all is straight into the batteries. Hope this helps Webbie

Thank you @RichardvdS for letting everyone know what had gone wrong in the end.

Invest in the Timer. I use a heat pump for hot water but it only runs while the sun is up. so the timer turns it on at 08:30 and off at 18:00. I am completely off grid thou so making sure i have sunlight coming in to power things is a lot easier and cheaper than having lots of extra batteries to hold that power. In your case you would set the timer for when the power you buy is at it's cheapest, So here if i was buying power i would have it turning on at 23:00 and off at 04:00 if i was connected to the grid. Unless your oven is broken i wouldn't be changing it over. Not because i don't like gas, because i do and i have a gas oven, but if your trying to future proof your costs then in the short term you may be better but in the long term with carbon emissions getting more and more attention then the price for the gas will start going up and very quickly i would think. In the short term i will keep using gas but in the long term I'm already planing on what will be needed to have a electric stove in use. If your not off grid then the stove does not need the battery to support it. In short if the oven costs you 1k how much power will that same 1k buy you and then how much cheaper is the gas at today's prices. you may end up using the old oven for 2-3 years before you actually break even on the purchase costs, but will the gas stay the same price for long to keep the ongoing fuel costs a cheaper option?

Good point @Chris Louw Operating voltage of 40V to 115V means no charge happening until full sun voltages are achieve in the 10 panels in parallel. If they are getting charge at 35v odd then they are lucky but wasting so much potential lower sunlight generation. This is something i didn't think about in my reply

I have 2 and 4. My battery cables are 70mm² and the 2nd option does them fine on the brand Lug i use(copper) but no so well on the harder cheap lugs a lot of people buy. the clamp does them but without the leverage the top one offers it's a lot of extra pressure you need to apply. My smaller crimpers look like the one in #4 but i dont have the extra MC-4 stuff with it. I do however have 5 or 6 different Jaw moulds i can change over so they do just about anything up to 25mm² (i think that was the largest crimp anyway) but really only use them for the smaller stuff. I use the other set for anything over 10mm²

Hmm i don't share your opinion. 10 x 275w panels at 38.6VOC = 2750w / aprox 35vmp = 78.57 Amps. That's a hell of a lot of amps going down the PV lines to me. I would really hope these lines are super large in size and super short in length. Do what @jumper has said and make your system groups of 3 panels in series. 3 in series x 38.6V = 115.8V VOC so even with 10% extra on a really cold sunny day there is plenty of margin before you reach the 145V the inverter supports. 4 in parallel x 7.85 amps = 31.4 Amps Much safer loads for the PV cables to handle. So the 3 in series combined with 4 in parallel is by far the safest option for you. Far safer to have higher voltages and lower amps but make sure you stay well under the 145VOC the inverter can handle. Just under is not good enough because at colder temps to the 25 Deg C they rate the panels at the VOC will increase. In my case i get 10% extra voltage at 3 deg c compared to the 25 deg so it is something you need to account for or you learn the hard way like i did when in the middle of winter the inverter shuts down due to the excessive solar voltage coming in.

To many variables in there to be a standard shopping list. I.E inverter size, battery size, charge/discharge rates, exposed/hidden in walls and distance required will determine your battery cable size. Same goes with panels for cable sizes. each has to be worked out based off real data for your intended setup. Plenty of people start with cables that are two small for the loads they actually use. in the short term it works in the long term though this is how fires start. For me i always look at the highest figure so your 5kw inverter might be able to handle 8kw for 5-10 seconds. This 8kw is what i would use to base my cables off and then add 15% extra. Yeah it costs more up front but it means as the cables degrade with time I'm not having to worry about replacing them or a fire starting out in one. Distribution boards are sized according to how many circuits you want in them. Once again i do things the expensive way and have way more circuits then most homes the same size. To me this is making the home future proof as homes built even 50 years ago didn't have the power loads we have today so more circuits gives me more options in the future. Easier to add the power lines at the one time rather than adding them years down the track kind of mentality. But that said I'm building my own place and not retrofitting so more options open to me than most. Real world data is the most important information you require. Buy a power meter that you can plug in and start looking at what loads your devices actually use and when they are all used. Then start working out what inverter size you need, as a 5kw inverter is useless if a peak load of 9kw is happening even for a few seconds. Best money is spent on the cheap meter to get the right system rather than spending thousands on a setup you think will do what you want and find it was all to small from the get go. Once you have all that work out what you think and then post it on here and plenty of people will be able to check your maths and give you feedback that's actually going to work. We all look at things in different ways so also knowing where your planing on going helps. ie starting with 1 inverter but plan to add a second later when funds are available will change the size of cables i would be working on from the start rather than having to upgrade the cables when you add the second inverter and throwing away the old cables. Hope this helps you get started Webbie

I first started off with a Must 5kva inverter, 9.6kva batteries (Gel) and 1.5kw worth of panels with no grid connection at all. The inverter didn't have to worry about half your gear and worked mostly for the loads we put onto it. The problem comes when your not able to control the loads. Ie fridge, freezer kicking in. With what you are listing i would think you will probably be running into problems. I.e pool pump running for 4 hours, dishwasher requiring 3 hours it becomes very hard to balance your energy load. We had a 50L hot water system that when i turned it on, if the pump was running and the fridge turned on then it would overload the inverter. of course this depends on the appliances as my new 600l fridge draws 1/4 the power of my old 430L fridge did. You could use this as a starting spot but things like the inverter which you can parallel to increase the power might have gone out of production and you can't parallel units that are not the same, when your ready to upgrade. If i had that lot of gear and wanted that setup then i would start by making a separate power circuit which is just the solar and start putting the things that run all the time onto that circuit. This would reduce your energy costs and give you a good starting with what you can and can't do with solar off grid. to start with off grid was all about load balancing and having to choose what you required as a higher priority. Also the difference between summer and winter in terms of power is big. 4 less hours of sunlight = more power running things from the batteries required. Keep a diary for a week and list what is running at what time of the day. I would recommend buying a cheap load meter which you can move from device to device and see what loads they actually do require. See what start up load and running loads each device uses and then work your system based on what you actually have already in use and the way you are currently using them. it might be a pain for a week keeping track of everything but the better you know that the better you can prepare. I.e if you have 1 person running the microwave, 1 person having a shower and 1 person using the hairdrier even if it is for only a few seconds of cross over could be the difference between inverter handling the load vs tripping from overload. Things like the pool pump and dishwasher i would only run during sunlight periods. Overcast or winter days though PV input may not be as high as you would like so the more your running on those days the less recharge is going into the batteries. End of the day it is well worth the $20 to buy the meter and run around for a week seeing what your loads really are and when you doing it all. Better the mathematics going in the better the mathematics will be coming out. It may just be better for you to spend more money on a bigger solar array and change to using all the power hungry gear during the day when the solar is free power for you and only buying the small loads for overnight. I know a few people who wanted to go off grid and i advised them to go this way instead just to see what completely off grid feels like before they have the expense of batteries and rewiring. For some the found the power bills dropped enough that they no longer cared about going off grid. Others decided working to a sun's up so i can do stuff rule was simply to hard so continue to pay the big bills. There is no easy one size fits all so please do the math's. Putting a good PV system on the roof now means you already have panels ready for when you switch to off grid later, so it's not a one way or the other sort of idea.

c) High Voltage: If charging voltage above 54V, battery protection will turn on. Solution: Check whether voltage is too high or not, if it is, to change the settings on power supply side. That is right in the Pylontech US2000 Battery Manual on page 22 out of 23 in mine. Pylontech's response to me was in fact in relation to the protection features reference above. To me the fact a error occurred and the system just resets itself is a major problem. How is a user going to know the problem has occurred to correct the settings in the system? Passive vs Active BMS on cell balancing i don't give a rats ass about as that is not protection that is balancing. But when protection is required then all BMS's should be Active. This is the only way to make a situation change from unsafe to safe and make the user aware that something needs to be checked out. If the BMS is Passive in regards to the protection than Pylontech should be honoring there warranties where over voltage has occurred due to misleading information. Maybe the clear warnings you remember seeing was added by your supplier but there is nothing that really stands out in any of the documentation i have from any of my batteries (2 V1.1, 2 V2.4 and 1 V3.4) End of the day with all the regulations and standards quoted in the world it is simply to easy for all these companies to side step them. I will never buy another Pylontech product. This creates a problem for me as i had planned on doubling my bank in the coming 2 years and now i will have to look at replacing them instead.

If you are running 3 phase equipment then a problem can occur, but most don't run that sort of equipment and really only need a single phase. Most Grid suppliers will tell a installer which phase they would prefer the inverter to be installed on so they can balance the phases. With 3 phase and some equipment a difference of a small number of volts between the phases can cause havoc hence the reason why they choose where it goes. Some companies are allowed to test the phases and then add to the lowest phase but this will depend on your area. Most simply convert there whole house to run on a single phase (the same phase as given above) as it's a lot easier and never have to worry about balance issues and makes things simpler for all parties envoled.

@RoannG i had a Must PV1800 previously but do not have it anymore as it finally died after years of faithful service. My PV1800 inverter supported lithium batteries but it had no BMS communications built into it. So you just set the inverter to lithium in the battery choice and manually set the values the inverter will use to charge and discharge. As for using it with Solar Assistant you require a USB to serial adapter and then the serial to custom RJ fitting depending on the model. you will find the pin outs for the custom cable in the battery's manual. Should be easy enough to get someone to change the serial plug over in any hobby electrical store. Hope this helps

Personally I went with the smaller ones. having two batteries means one can be damaged and the other keeps you going in a limited capacity. Having only one battery means if something goes wrong you have nothing to keep you going. 2 x smaller units cost more and has more cables needed but still a better choice. If later on you can always add a larger battery to the mix if you want more juice.

Just wanted to let you all know that i have reported Pylontech to the ACCC over this matter. Though they won't help my situation, i do think if anyone who has had the same warranty denied by pylontech reports it to the ACCC, then maybe someone else might actually get the warranty they paid for from Pylontech. The more people who do report them the better the odds of the ACCC taking action. Here is my reasoning. 1) If the battery BMS is passive only which Pylontech have informed me, then the battery protection is only for a very short time (as my logs show a 4 second window between entries in some cases) and not a true disconnect as i would expect, then a lot of the errors they claim void the warranty would not have occurred at all. All the extra over voltage entries occurring due to this, would lessen my entries 30 fold if i didn't make changes to the inverter and just restarted the batteries no knowing what had happened. 2)If the battery does not disconnect how is a end user to know when a over voltage event has ever happened? Is the user required to sit in front of the unit staring at the little red error LED waiting for it to go on for the 3 seconds that the error is happening over before the BMS resets and things return to normal status? 3) Pylontech does not make the Batteryview software publicly available for people to check the errors on the batteries to find any faults to correct. 4) having a passive BMS that does not disconnect the battery is misleading and unsafe. I and I'm sure plenty of others purchased these batteries because they thought the BMS would protect the battery against most of the potential problems that do damage to the cells. 5) Saying you have to have an approved inverter when they don't publish what inverters they do support up front. And if they did and they change what brands they support would your support inverter at time of purchase be claimed as a unsupported inverter years later when you try to make a claim? Good luck @OzzyMozzy

The Event log files do not seem to record all the details. IE to me the most important event that should be recorded was a date of first use, startups and shutdowns. but they only record "warning and alarm level events". There is a history file that also can be downloaded from the batteries but they only show the last 30 days of activity at 30 minute intervals. This log does show power ups but not any power downs in that time.

Just to update you all This is the reply i got today from Pylontech "Let me clarify that it is not because your battery has reported a fault that your 10 year warranty has disappeared, it is because the 54V has exceeded the maximum charge voltage indicated in the battery manual and this is considered improper use and therefore we cannot offer a warranty for subsequent failures, customers have the right to decide how to use their batteries, but our warranty can only be offered to batteries that have been used properly." So searching for the warranty and manual i received with the batteries i go as i don't recall any of that. Looking through the manual i got with the batteries there is no maximum charge voltage of 54V listed. In 2.2 Specifications on page 4 it does state charge voltage 52.5 ~ 53.5 (I take this as a suggested charging range) but certainly no mention of a maximum charge of 54 volts listed here but maybe it is implied 53.5V is the maximum? On page 22, under trouble shooting 5.2 c) High Voltage: If charging voltage above 54V, battery protection will turn on. Solution Check whether voltage is too high or not, if it is, to change the settings on power supply side. So the battery protection should have shut the batteries down if the voltage is over 54V and a manual reset should have been done to correct the problem is the way i see this. The fact this error occurred two or three times in a row, 4 seconds apart from one another, says no battery protection happened to make a person aware there was a issue to look into at all, as i would expect to happen, but because of this my warranty is voided according to them. This is the very reason why i think a warranty claim on the defective product is required more than ever. I Don't know about you OzzyMozzy but i sure feel like i threw away 13K on these batteries. I Wish you better luck than what I have seen.

Funny enough i have had a issue with 2 US2000 batteries. I had to shut the system down because i knew i didn't have enough power to last the night and wanted to preserve the charge for the next morning to use. Shutdown at 34% SoC and startup 7 hours later showed 2 batteries at 4% SoC. Logs showed before shutdown the charge was at 34% and 4% the next entry hours later. Contacting Pylontech they had me download and send them the logs. which i done over 2 days as they took so long for the first two batteries to download and bad weather meant i wanted to conserve power. They have said "We actively hope to solve your problem, but two of your batteries have been recorded as frequently overcharged and I have found that your inverter MPPsolar 7248Max is not in our compatibility list, these are signs of improper use and will not be covered by the warranty." I responded staiting that the inverters are in fact Voltronic axpect rebadged which are on their supported list and that any over voltage should have been handled by the BMS to prevent any damage. The really annoying part of this though the over voltage in my case was done 3 years ago before i even brought the batteries and not a ongoing problem (no over volt in the 2.5 years i have had the units and only 4 other events in this period). There response "Our battery's passive protection mechanism, MOSFET, is only activated when the battery parameters are extremely abnormal (Short circuits, high currents, high voltages, etc. that can damage the circuit and may cause safety events). The battery BMS only uploads its own voltage, recommend charge and discharge current to the inverter,, and the time to stop chargind/discharging is controlled by the inverter. Therefore, if the battery is still being charged despite reaching the alarm value, the voltage at the inverter must be higher than 54V (otherwise there would be no voltage difference between the battery and the external power source and it therefore would not be charged) as well as inverter does not react to the data uploaded by the battery according to the preset logic." So to me the high voltage (54v) that the batteries received over a 17 day period in 2020 were not a high enough value for their BMS to worry about so meaning a very low chance of a problem occurring, causing them to say the warranty is not valid is just wrong. Will be watching to find out how they treat you.