Is there any significant difference in charging these types of battery to 70% then discharging to 20% and charging to 100% then discharging to 50%? For example, in terms of the life of the battery.
Graham
About charging and discharging batteries
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Dave Foster
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LFP batteries are very resilient and ideally suited to solar charging - they don’t mind being charged to 100%, or 70% but must not drop below 10% minsoc for any extended period of time.
From a battery cycle perspective, the BMS has a watt counter so if you charge to 100% then discharge to 50%, charge to 100% and discharge to 50% you will only have used one battery cycle - and LFP are capable of a considerable number of cycles.
The BMS likes to see a deep discharge (to 10% minsoc) and a full charge to 100% once every month or two - this helps it to train its limits so it can provide more accurate soc and kwh remaining counters,
In general best advice is to use them as much as you can, don’t let them overheat (>50C) and don’t let them drop below 10% minsoc and they will provide many years reliable operation.
From a battery cycle perspective, the BMS has a watt counter so if you charge to 100% then discharge to 50%, charge to 100% and discharge to 50% you will only have used one battery cycle - and LFP are capable of a considerable number of cycles.
The BMS likes to see a deep discharge (to 10% minsoc) and a full charge to 100% once every month or two - this helps it to train its limits so it can provide more accurate soc and kwh remaining counters,
In general best advice is to use them as much as you can, don’t let them overheat (>50C) and don’t let them drop below 10% minsoc and they will provide many years reliable operation.
What I'm reading on the internet (remembering the quote from Abraham Lincoln I read on the internet, viz that "you shouldn't believe anything you read on the internet") is that there's some softness in the lower limit, i.e. from some value a bit above 10% min charge level, there's some reduction of battery life, where that effect increases with lower min charge. What I've not found is anything that gives any real numbers on how much the life is degraded at what min charge and, just as importantly, how often that minimum is reached and for how long it's sustained.
The suggestions seem to be that there's no effect at 20%, and a "significant", but otherwise undefined effect at 10% min. There do seem to be suggestions that the effect diminishes about logarithmically, i.e. there's a much bigger change in effect between 11 and 10 percent minimum charge than between 15 and 14 percent, etc.
I can, roughly, calculate the costs of setting the minimum too high, in terms of how much power I would draw on an average day at a higher tariff, etc. But without knowing the cost of setting it too low, in terms of how much sooner I would have to replace the battery, I have no rational basis for setting the Min SoC.
I'm thinking to compromise by setting Min SoC to 15%, and Max SoC to a level where I get down to 15% a few times a month - mostly on rainy Sundays. The latter being to maximize how much solar power I use rather than export, which I can also calculate a rough cost for exporting power I could have used if I hadn't charged the battery so much at night - I expect I'll have to change the Max SoC a few times a year.
But I'm aware and don't like that those settings are hardly more than a guess.
Graham
The suggestions seem to be that there's no effect at 20%, and a "significant", but otherwise undefined effect at 10% min. There do seem to be suggestions that the effect diminishes about logarithmically, i.e. there's a much bigger change in effect between 11 and 10 percent minimum charge than between 15 and 14 percent, etc.
I can, roughly, calculate the costs of setting the minimum too high, in terms of how much power I would draw on an average day at a higher tariff, etc. But without knowing the cost of setting it too low, in terms of how much sooner I would have to replace the battery, I have no rational basis for setting the Min SoC.
I'm thinking to compromise by setting Min SoC to 15%, and Max SoC to a level where I get down to 15% a few times a month - mostly on rainy Sundays. The latter being to maximize how much solar power I use rather than export, which I can also calculate a rough cost for exporting power I could have used if I hadn't charged the battery so much at night - I expect I'll have to change the Max SoC a few times a year.
But I'm aware and don't like that those settings are hardly more than a guess.
Graham
Graham Fountain
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Dave Foster
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LFP technology is still a relatively new 'technology/chemistry', and unlike Lion there isn't any real life history that back up the manufacturers claim, there are quite a few research papers about that look at the effects of temperature (the most significant effect on battery life) and also ageing from repeated cycle use.
It sounds like you know this already but you have to be very careful when looking at studies as they are chemistry specific, Lithium Ion has very different characteristics to Nickel Managanese Cobalt (NMC) and LiFePO4 (LFP).
The FoxESS LFP batteries are warrantied / rated at a 90% depth of discharge for a specific number of cycles (the manufactures sometimes quote the lifecycle as a maximum throughput) - and yes the better you treat them, the longer they will last - but as already mentioned the most significant effect on ageing is charging at high temps so avoiding high charge rates when the batteries are very hot will have the most effect on their life.
In practice it will depend on how you use the batteries, if like me during winter you will be charging them from a low cost tariff (Octopus Go etc..) having the minimum SoC set to 10% is less of an issue than if you only charge from solar when there is not much surplus. These batteries have an internal drain of approximately 3% per month and so if they are not going to be in charge for any sustained period it is best to have them charged to 50% beforehand.
Also going back to winter, low temperatures have an effect on their capacity (not their lifetime) this is only a temporary effect and they recover when temperatures recover. But low temps can in operation cause them to drop below the minimum minsoc of 10% as they will not allow a charge to take place if very cold.
The usual advice I give is to go with a 15% to 20% minimum SoC in winter, but in summer months drop that to 10% when they are not likely to reach that low/and if they do it won't be for very long, and, the temperature will be good (~20C) ; and most importantly always follow the manufacturers specifications around temperature.
A final thought is whether you have the EPS function enabled, this is effectively where the inverter provides critical circuits with power during loss of grid power - if you do you may wish to have a higher 'minsoc on grid' than minsoc so that there is some margin to be used in the event of power fail.
It sounds like you know this already but you have to be very careful when looking at studies as they are chemistry specific, Lithium Ion has very different characteristics to Nickel Managanese Cobalt (NMC) and LiFePO4 (LFP).
The FoxESS LFP batteries are warrantied / rated at a 90% depth of discharge for a specific number of cycles (the manufactures sometimes quote the lifecycle as a maximum throughput) - and yes the better you treat them, the longer they will last - but as already mentioned the most significant effect on ageing is charging at high temps so avoiding high charge rates when the batteries are very hot will have the most effect on their life.
In practice it will depend on how you use the batteries, if like me during winter you will be charging them from a low cost tariff (Octopus Go etc..) having the minimum SoC set to 10% is less of an issue than if you only charge from solar when there is not much surplus. These batteries have an internal drain of approximately 3% per month and so if they are not going to be in charge for any sustained period it is best to have them charged to 50% beforehand.
Also going back to winter, low temperatures have an effect on their capacity (not their lifetime) this is only a temporary effect and they recover when temperatures recover. But low temps can in operation cause them to drop below the minimum minsoc of 10% as they will not allow a charge to take place if very cold.
The usual advice I give is to go with a 15% to 20% minimum SoC in winter, but in summer months drop that to 10% when they are not likely to reach that low/and if they do it won't be for very long, and, the temperature will be good (~20C) ; and most importantly always follow the manufacturers specifications around temperature.
A final thought is whether you have the EPS function enabled, this is effectively where the inverter provides critical circuits with power during loss of grid power - if you do you may wish to have a higher 'minsoc on grid' than minsoc so that there is some margin to be used in the event of power fail.
Thanks, that looks a fairly comprehensive cover of the general rules. I'll need to study it for a while, though.
I take it that the temperature I should be concerned about is the battery temperature as monitored on the app. However, it worries me that, as someone else has noted, I’m seeing higher ambient temperatures than battery temps; especially when charging at 5 kW overnight. Is it possible/likely the sensors are swapped?
As to whether I have EPS enabled, I assume not - I assume that requires modifications to the main fuse box, so the fuses supplying the freezer and the CH boiler, etc., are supplied separately from the inverter. And I'm not aware there were such mods made, and certainly can't see any. But we have a reasonably reliable mains supply (if saying that is not tempting fate): we've only had significant cuts in the past when the Gas Board have been out digging. Even so, I have wondered what will happen if we do have a cut; especially if we would be exporting at that time.
Graham
I take it that the temperature I should be concerned about is the battery temperature as monitored on the app. However, it worries me that, as someone else has noted, I’m seeing higher ambient temperatures than battery temps; especially when charging at 5 kW overnight. Is it possible/likely the sensors are swapped?
As to whether I have EPS enabled, I assume not - I assume that requires modifications to the main fuse box, so the fuses supplying the freezer and the CH boiler, etc., are supplied separately from the inverter. And I'm not aware there were such mods made, and certainly can't see any. But we have a reasonably reliable mains supply (if saying that is not tempting fate): we've only had significant cuts in the past when the Gas Board have been out digging. Even so, I have wondered what will happen if we do have a cut; especially if we would be exporting at that time.
Graham
Graham Fountain
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Dave Foster
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You would know if you had the EPS installed as it would have a seperate consumer unit for the critical circuits and when the mains grid fails it automatically fails over to the EPS circuit on battery - As you don't have it you can set both your min soc's to the same value.
You are right to be a bit sceptical about the 'battery temperature' it's actually the inner temperature of the BMS itself which is usually a few degrees warmer than the batteries.
If you are really interested in the analytics, getting a Home Assistant would really benefit you - it is a small micro-processor based device running a bespoke home automation OS that connects directly to the Inverter via it's RS485 connections and provides access to a considerable number of sensors that you don't get on the app/website.
Without wishing to send you down a rabbit hole (they are very addictive), this is just some of the sensors my Inverter is reporting in near real time.
With this information you can get early warnings of over-heating, modify the minimum SoC's automatically, change the charge periods, a great many things.
My home assistant is running on a Raspberry Pi4B with small SSD drive, so a fairly low cost investment and provides me with all the statistics I could ever need.
You are right to be a bit sceptical about the 'battery temperature' it's actually the inner temperature of the BMS itself which is usually a few degrees warmer than the batteries.
If you are really interested in the analytics, getting a Home Assistant would really benefit you - it is a small micro-processor based device running a bespoke home automation OS that connects directly to the Inverter via it's RS485 connections and provides access to a considerable number of sensors that you don't get on the app/website.
Without wishing to send you down a rabbit hole (they are very addictive), this is just some of the sensors my Inverter is reporting in near real time.
My home assistant is running on a Raspberry Pi4B with small SSD drive, so a fairly low cost investment and provides me with all the statistics I could ever need.
I've thought about the home assistant option, but it looks more involved to implement than I want. I don't mind buying a Pi and SSD, and probably aren't worried by the physical installation and cabling etc. - even running an Ethernet cable into the loft wouldn't phase me. But I don't want to get into Linux and software installation, and I'm not putting a VP on my laptop for any reason.
Graham
Graham
Graham Fountain
If I was to install and connect a Linux machine running home assistant to the inverter, would I be able to monitor that from and extract data to a Windows machine over the wifi, e.g. via a browser?
Graham
Graham
Graham Fountain
The data is logged on the Linux host running HA, but you access it via your LAN, using the web interface or the app.
As for Linux, if you install the fully integrated OS version of Home Assistant then you don't have to worry about any of the Linux side of things at all. It's all done via the web GUI.
I'm wondering what you mean by a VP in this context?I'm not putting a VP on my laptop for any reason.
As for Linux, if you install the fully integrated OS version of Home Assistant then you don't have to worry about any of the Linux side of things at all. It's all done via the web GUI.
Sorry, I meant virtual machine, i.e. logical partition, not virtual partition.
But if I can install a Linux box near the inverter running HA, and see the data that records from a separate Windows 10 machine, that would do. So what app would be running under Windows 10 to log the data and apply control?
I still want to compile that data with the CSV file data from Octopus in Excel, as the consumption and export data values there are integrated ones, not point in time samples multiplied by the sample intervals, with all the inaccuracy that implies. To put it another way, those are the data on which I get charged.
What I really want from the data from the inverter is solar energy (kWh) generated over the day and SoC. I currently have to get the solar energy values from the stats display for the S2000 and S1500 inverters in the app. I'll live with the solar energy data being from point samples, not integrated.
I also want to set Max SoC from the Windows machine, where I understand that needs an RS485 connection to the H1 inverter.
So, are the specs I need for the Linux box to run HA anywhere, i.e. how fast a processor, cores, RAM, and NV Storage, etc. I'd probably go with a Pi as having the biggest support base. So, in that case, which model would do, and could the NV RAM be an SD card, or does it need an SSD, and how big?
Graham
But if I can install a Linux box near the inverter running HA, and see the data that records from a separate Windows 10 machine, that would do. So what app would be running under Windows 10 to log the data and apply control?
I still want to compile that data with the CSV file data from Octopus in Excel, as the consumption and export data values there are integrated ones, not point in time samples multiplied by the sample intervals, with all the inaccuracy that implies. To put it another way, those are the data on which I get charged.
What I really want from the data from the inverter is solar energy (kWh) generated over the day and SoC. I currently have to get the solar energy values from the stats display for the S2000 and S1500 inverters in the app. I'll live with the solar energy data being from point samples, not integrated.
I also want to set Max SoC from the Windows machine, where I understand that needs an RS485 connection to the H1 inverter.
So, are the specs I need for the Linux box to run HA anywhere, i.e. how fast a processor, cores, RAM, and NV Storage, etc. I'd probably go with a Pi as having the biggest support base. So, in that case, which model would do, and could the NV RAM be an SD card, or does it need an SSD, and how big?
Graham
Graham Fountain
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Dave Foster
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If you use a Raspberry Pi, it's totally self contained, you don't need to worry about Linux it's all hidden below the Home Assistant application (unless you want to deep dive).
You access it via a web browser on your windows pc, and it will have all the statistics you're looking for - it records all key stats in its energy database all of which are accessible via a normal web browser, or you can load an app on your phone, tablet and view it on there.
That's what the energy dashboard looks like for me today (not very sunny), and it does that 'out of the box' with very little configuration required, other than the decision of how to connect - via the cloud API (which used the FoxESS servers and it's 5 minute update cycle), or via RS485 for real time and local control.
If you have the mobile app on your phone you can send notifications to yourself, so for example if the solar forecast isn't enough to charge the batteries and you haven't set a charge etc..
if the inverter is connected via RS485, you will also have the ability to set charge periods, min socs, and you can do it automatically by writing your own automation.
With a bit of minor adaption you can create your own dashboard which shows only the key sensors, statistics and graphs you are interested in.
You shouldn't need to export data to your pc as it is a self contained system, backups yes but not really the data - but if you want you can export the data to csv and analyse it on your PC or NAS.
It is recommended to have a Raspberry Pi4B with min 2GB ram (with preferably 4GB) and a smallish 128GB SSD drive which connects to it's USB port - you can run off the SD card but it's not recommended.
You access it via a web browser on your windows pc, and it will have all the statistics you're looking for - it records all key stats in its energy database all of which are accessible via a normal web browser, or you can load an app on your phone, tablet and view it on there.
If you have the mobile app on your phone you can send notifications to yourself, so for example if the solar forecast isn't enough to charge the batteries and you haven't set a charge etc..
if the inverter is connected via RS485, you will also have the ability to set charge periods, min socs, and you can do it automatically by writing your own automation.
With a bit of minor adaption you can create your own dashboard which shows only the key sensors, statistics and graphs you are interested in.
You shouldn't need to export data to your pc as it is a self contained system, backups yes but not really the data - but if you want you can export the data to csv and analyse it on your PC or NAS.
It is recommended to have a Raspberry Pi4B with min 2GB ram (with preferably 4GB) and a smallish 128GB SSD drive which connects to it's USB port - you can run off the SD card but it's not recommended.
I'd argue the most widely supported platform is x86, and there's loads of mini PCs on eBay that support the minimum (or even a generous) spec for HA. Same as the Pi, once installed you don't have to touch the Linux underpinnings.
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Dave Foster
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Yes I wouldn't disagree and they have far more hp than the Pi, probably around the same price to put one together - I just like the Pi's self contained nature and low 6W power usage.
Your average ex corporate SFF PC is arguably just as self contained as a Pi? But yes, it will almost certainly have higher power consumption. If you think you might want to get a bit more involved (maybe logging to InfluxDB and analysing with Grafana?) then that increased power usage might be justifiable. But yeah, if you just want a data logger for some basic solar data then the Pi option is going to be (marginally!) cheaper to run in the long term.
So, something like this https://www.ebay.co.uk/itm/256038764507 ... 3b9d197fdb with an £8ish 120Gb SSD? I assume I can download HA to a USB stick and transfer that way. Cloning the SSD that's in it might be a problem if it's an M.2.
As to exporting the data to the Windows 10 laptop, I really think I do want that. But CSVs will do, even if there are data for more parameters than I need.
What I think I want is to put the box running HA in the loft with the inverter, etc., and do all the control and analysis from my laptop, more or less as I do now, but with better (and local) access to the data and control of Max SoC, etc. If I have to have something like a vt100/tty emulation on the laptop, that's ok.
I have a Gigabit Ethernet switch on the landing that connects to the WiFi hub and so the laptop. So it's no big thing to run a cable into the loft.
But part of the problem is that my home-office/workspace is one end of the kitchen-dining table, so there's a limit to how much stuff I can have there.
The alternative to the HA box in the loft and a Windows laptop on the table might be an Ethernet connection between the inverter and the hub, and something like another laptop running HA over Linux on the table. But I'd then have to re-learn what I have learned to do in Excel in some other spreadsheet (open office?) to do the level of data analysis I want. And I'm fairly sure there are programs, apps, and stuff, I want to keep using on the Windows laptop. So that's a lot less than ideal for me. I also suspect it's a bit more expensive than an HA box in the loft, etc.
Graham
As to exporting the data to the Windows 10 laptop, I really think I do want that. But CSVs will do, even if there are data for more parameters than I need.
What I think I want is to put the box running HA in the loft with the inverter, etc., and do all the control and analysis from my laptop, more or less as I do now, but with better (and local) access to the data and control of Max SoC, etc. If I have to have something like a vt100/tty emulation on the laptop, that's ok.
I have a Gigabit Ethernet switch on the landing that connects to the WiFi hub and so the laptop. So it's no big thing to run a cable into the loft.
But part of the problem is that my home-office/workspace is one end of the kitchen-dining table, so there's a limit to how much stuff I can have there.
The alternative to the HA box in the loft and a Windows laptop on the table might be an Ethernet connection between the inverter and the hub, and something like another laptop running HA over Linux on the table. But I'd then have to re-learn what I have learned to do in Excel in some other spreadsheet (open office?) to do the level of data analysis I want. And I'm fairly sure there are programs, apps, and stuff, I want to keep using on the Windows laptop. So that's a lot less than ideal for me. I also suspect it's a bit more expensive than an HA box in the loft, etc.
Graham
Graham Fountain
You can also define your own sensors if there's calculations you want done that HA doesn't do by default. You can also define "utility meters" to give you consumption by day, week, month, whatever you like.With a bit of minor adaption you can create your own dashboard which shows only the key sensors, statistics and graphs you are interested in
My point being, done right HA has the potential to render your Excel analysis workflow redundant, and give you better granularity, accuracy etc.
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Dave Foster
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That kit you linked on ebay sadly won't do it, it's basically an emulator that runs the raspberry pi dashboard - not a raspberry itself - for the Pi you would need the physical hardware as this is regularly tested to work with Home Assistant. It will run on a Pi 3B+ (you must get the + if you want to connect it to an SSD).graham wrote: ↑Sun Aug 06, 2023 4:08 pm So, something like this https://www.ebay.co.uk/itm/256038764507 ... 3b9d197fdb with an £8ish 120Gb SSD? I assume I can download HA to a USB stick and transfer that way. Cloning the SSD that's in it might be a problem if it's an M.2.
As to exporting the data to the Windows 10 laptop, I really think I do want that. But CSVs will do, even if there are data for more parameters than I need.
What I think I want is to put the box running HA in the loft with the inverter, etc., and do all the control and analysis from my laptop, more or less as I do now, but with better (and local) access to the data and control of Max SoC, etc. If I have to have something like a vt100/tty emulation on the laptop, that's ok.
I have a Gigabit Ethernet switch on the landing that connects to the WiFi hub and so the laptop. So it's no big thing to run a cable into the loft.
But part of the problem is that my home-office/workspace is one end of the kitchen-dining table, so there's a limit to how much stuff I can have there.
The alternative to the HA box in the loft and a Windows laptop on the table might be an Ethernet connection between the inverter and the hub, and something like another laptop running HA over Linux on the table. But I'd then have to re-learn what I have learned to do in Excel in some other spreadsheet (open office?) to do the level of data analysis I want. And I'm fairly sure there are programs, apps, and stuff, I want to keep using on the Windows laptop. So that's a lot less than ideal for me. I also suspect it's a bit more expensive than an HA box in the loft, etc.
Graham
It will work on a number of different platforms listed in here (https://www.home-assistant.io/installation/) - because of the recent past chip shortages Raspberry Pi's have been difficult to get hold of and the second hand market is high - the board is now back in stock https://thepihut.com/products/raspberry-pi-4-model-b butit'll be a while before the second hand prices come down to sensible levels.
As Calum said an ex corporate SFF mini pc is a good option and may well be the better price point at the moment - and you could run a second laptop with a VM running home assistant as well.
If, by "You can also define your own sensors" you mean you I can include data imported from a CSV, then that could make the Excel analysis redundant if I transpose the calculations from Excel to HA. I've said why I think I need the Octopus data in the CSV files. But even if I can import the CSV data into HA and transpose the calculations to it, Excel is an easy way to experiment [play] with the analysis, and one I'm already very familiar with. So, for at least as long as there are different things I want to analyse the data for, I think I want to use Excel for that.calum wrote: ↑Mon Aug 07, 2023 9:04 amYou can also define your own sensors if there's calculations you want done that HA doesn't do by default. You can also define "utility meters" to give you consumption by day, week, month, whatever you like.With a bit of minor adaption you can create your own dashboard which shows only the key sensors, statistics and graphs you are interested in
My point being, done right HA has the potential to render your Excel analysis workflow redundant, and give you better granularity, accuracy etc.
But I may have found a solution to the HA box in the loft: I remembered I have an old HP laptop with a Broadwell i3 (5010U) and 8GB of RAM. The battery is a bit tired, so I'll probably run without it if HA can be made to autorun on boot-up - with the BIOS set to boot on AC -; and I'll have to swap the HD for an SSD - it was too slow and still has stuff on it I may want. But that laptop owes me nowt, and I reckon it should do for Linux/|HA if it gets a Wi-Fi connection in the loft. I can at least get it set-up, connected to the Wi-Fi, and talking to the Windows laptop while it's downstairs.
I think I would connect that to the inverter by USB, as the RS485-USB IF units are very much cheaper than RS485-Ethernet TCP-IP ones in the UK - though I would have to redo the connection if I found I really did need to connect direct to the hub.
But all that still depends on the Windows machine being able to remotely access the data that the HA box has garnered. And I'm still not sure I understand how that would work.
Graham
Graham Fountain
I was wondering about installing Linux on that directly and running HA under that.Dave Foster wrote: ↑Mon Aug 07, 2023 10:59 am
That kit you linked on ebay sadly won't do it, it's basically an emulator that runs the raspberry pi dashboard - not a raspberry itself
So, with the x86 machine, I have to run Windows and a VM to run HA?
Graham
Graham Fountain
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Dave Foster
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You possibly could install Linux, and then run HA under a VM container - I guess it all depends how much spare time you have, and how well you know Linux, this is probably the hardest but most re-warding install.graham wrote: ↑Mon Aug 07, 2023 12:07 pmI was wondering about installing Linux on that directly and running HA under that.Dave Foster wrote: ↑Mon Aug 07, 2023 10:59 am
That kit you linked on ebay sadly won't do it, it's basically an emulator that runs the raspberry pi dashboard - not a raspberry itself
So, with the x86 machine, I have to run Windows and a VM to run HA?
Graham
Yes on the x86 machine it's a windows machine and you install the Home Assistant Operating System (which is Linux based) as VM, you don't need to know/learn Linux it's all well hidden away from you and all you have to concentrate on is getting the sensors and visual dashboard designed the way you want.
Oh, I assumed I could run HA directly over a native Linux OS - I don't know Linux well at all, but I was told by a man who says he knows what he's talking about that there'll be no issues installing it on an HP Pavilion Notebook 15-ab040sa from 2016.
So I was going to install Linux on the new SSD I'm getting for the old laptop, and then add HA. But I suppose I can extract the Windows key from the old HD installation, and reuse it to install Windows on the SDD. I only bought an £8, 128GB drive, so I hope that's enough for both OSs and the data storage.
My problem with installing HA on my personal laptop is I don't want a VM on it. I did once have a VM installed on a previous Laptop, which caused such problems that I can't ever go near that ever again. What those problems were is complicated, but assume it's a life-threatening issue.
In this case, with a machine that's in the loft, I can have a VM if I must. I'm just a bit concerned about the issues in having it autorun HA after a power cut. But if I had to, I guess I can fix those.
And I still don't get how I access the data HA has on that machine from another windoze machine.
Graham
So I was going to install Linux on the new SSD I'm getting for the old laptop, and then add HA. But I suppose I can extract the Windows key from the old HD installation, and reuse it to install Windows on the SDD. I only bought an £8, 128GB drive, so I hope that's enough for both OSs and the data storage.
My problem with installing HA on my personal laptop is I don't want a VM on it. I did once have a VM installed on a previous Laptop, which caused such problems that I can't ever go near that ever again. What those problems were is complicated, but assume it's a life-threatening issue.
In this case, with a machine that's in the loft, I can have a VM if I must. I'm just a bit concerned about the issues in having it autorun HA after a power cut. But if I had to, I guess I can fix those.
And I still don't get how I access the data HA has on that machine from another windoze machine.
Graham
Graham Fountain
There's a hiccup in the plan to use the HP laptop, in that the advanced bios access is locked by HP, and they want more than it's worth to unlock and make it boot on AC power. But, maybe, boot on LAN will do instead, as we don't see a lot of power cuts. I'll test that today. There are suggestions on the internet that the advanced bios access being locked also means I can't run Linux as the native OS, and will have to have HA on a VM under Windoze.
But just to check: If there is a power cut, then is the house load met from the battery and solar for as long as possible, and then shuts off when SoC gets to Min? Also, out of interest and if that's correct, what then happens if there continues to be solar - but by implication not consistently as much as the house load - and the battery SoC goes back up above Min? For example, how far above min before the inverter starts outputting power to the house?
Also, presumably HA is directly monitoring the inverter. So, if the laptop loses power and runs out of battery (the battery is part of why it's spare), is any data HA would normally gather lost, or is it stored in the inverter?
Graham
But just to check: If there is a power cut, then is the house load met from the battery and solar for as long as possible, and then shuts off when SoC gets to Min? Also, out of interest and if that's correct, what then happens if there continues to be solar - but by implication not consistently as much as the house load - and the battery SoC goes back up above Min? For example, how far above min before the inverter starts outputting power to the house?
Also, presumably HA is directly monitoring the inverter. So, if the laptop loses power and runs out of battery (the battery is part of why it's spare), is any data HA would normally gather lost, or is it stored in the inverter?
Graham
Graham Fountain
Unless your installers have specifically set up your system to automatically (or manually, for that matter) switch over to Emergency Power Supply (EPS) mode, if the power goes off the whole system shuts down and you are just as much without power as you would be without the solar or batteries.
Not sure about the advanced BIOS situation, as long as you can temporarily change the boot device to boot from a USB device, you should be able to install HA. The only concern is if you can deactivate Secure Boot as Debian Linux which is the underlying OS for HA won't work with Secure Boot. There seems to be some possible workarounds here that might be worth a go: https://techartful.com/access-advanced- ... ttings-hp/
If HA loses power then it stops gathering data. Most of what it's recording are snapshots of the values of registers inside the inverter's microcontroller, which change several times a second.
The inverter does have some internal counters for, I think, total lifetime PV output and maybe Lifetime power output? Dave Foster would know for sure.
Not sure about the advanced BIOS situation, as long as you can temporarily change the boot device to boot from a USB device, you should be able to install HA. The only concern is if you can deactivate Secure Boot as Debian Linux which is the underlying OS for HA won't work with Secure Boot. There seems to be some possible workarounds here that might be worth a go: https://techartful.com/access-advanced- ... ttings-hp/
If HA loses power then it stops gathering data. Most of what it's recording are snapshots of the values of registers inside the inverter's microcontroller, which change several times a second.
The inverter does have some internal counters for, I think, total lifetime PV output and maybe Lifetime power output? Dave Foster would know for sure.
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Dave Foster
- Posts: 1298
- Joined: Thu Oct 13, 2022 7:21 pm
The majority of people that have HA on an old laptop have it running under a VM, so I think that's the way to go - hopefully means that if you do have a power cut it's only for a short time and the laptop's battery will keep it running for the duration.
As Calum said because the inverter is grid tied, when you lose the grid the inverter goes into isolation and waits for it to return so in effect you will lose all the power in your house until the grid returns.
If you connect the EPS (it is a separate output connector on the inverter which would be feeding an separate consumer unit) anything attached to that can be maintained during the grid off period as long as you have enough battery to keep it going. During grid outages the inverter can still charge your batteries and if you have EPS it will feed that load.
If your HA machine powers off, you will lose any of the sensors that are real time for the period it is off as it will have missed that data, some of these sensors are used by the energy dashboard to track your usage, generation, feed in etc.. so there will be a missing hole in the data.
There are a number of 'total ' sensors that the inverter maintains and so things like battery charge/discharge today, load energy today, PV1 / 2 totals and solar generation today will all be maintained there so you would be able to work out what is missing - and you could poke them manually into the statistics so your day totals are still ok (i've done that a few times for people).
As Calum said because the inverter is grid tied, when you lose the grid the inverter goes into isolation and waits for it to return so in effect you will lose all the power in your house until the grid returns.
If you connect the EPS (it is a separate output connector on the inverter which would be feeding an separate consumer unit) anything attached to that can be maintained during the grid off period as long as you have enough battery to keep it going. During grid outages the inverter can still charge your batteries and if you have EPS it will feed that load.
If your HA machine powers off, you will lose any of the sensors that are real time for the period it is off as it will have missed that data, some of these sensors are used by the energy dashboard to track your usage, generation, feed in etc.. so there will be a missing hole in the data.
There are a number of 'total ' sensors that the inverter maintains and so things like battery charge/discharge today, load energy today, PV1 / 2 totals and solar generation today will all be maintained there so you would be able to work out what is missing - and you could poke them manually into the statistics so your day totals are still ok (i've done that a few times for people).
@Graham, when you get your HA set up you might want to have a look at this https://community.home-assistant.io/t/n ... ard/369450
Allows for export of selected history data to .CSV.
Allows for export of selected history data to .CSV.