jbroo

@PhotonSmart I have the same inverter. Been using it for about 3 months now with no issues. I have 2 x 200Ah LFP batteries (Securi-Prod brand from Regal). Also no issues so far. My charge settings are: Battery type: User Bulk charge: 28.4V Float charge: 27.2V More info below: I set the above after a lengthy calibration exercise to make sure the inverter reports the correct battery voltage, as referenced against the balancer reading and a multimeter. The balancer you can get here. I prefer the HA11 which has bluetooth so I can monitor from phone (you can get the cheaper dumb balancer or the one with LED display). Feel free to ask me any questions about this inverter, or check my other posts on the forums for mods, monitoring and other adventures.

Hi all, I'm new to the solar component of the game, I'm hoping to get some practical advice from the experienced solar folks on the forum. First, a breakdown of my current system: Synapse 3.0V+ 3000VA/2400W 24V inverter 2 x 12v, 200Ah LFP batteries in series (total 5.2kWh) HA11 battery balancer Raspberry Pi 1B running SolPipLog for monitoring The above is professionally installed via my DB board, with COC, etc, and provides great backup power for load shedding and outages. It excludes geysers, stove, kitchen appliances, and pool pump, but does include fridges. My consumption is generally between 200-600W at any given moment, with occasional peaks up to 2000W. I'm not in a position to rip and replace with a more robust Sunsynk 48V system, as has been suggested to me a number of times - I'd just like to make the best of what I have. Now, the inverter (an Axpert type) is quite limited in terms of solar capability. Below is the spec of what it can take: The panels I'm keen to get are the Jinko Tiger 475W: I've used @Chris Hobson's brilliant solar calc tool, and it looks like the best I can do on the above spec is 2 x 450W-ish panels in parallel. Panels in series exceed the permissible cold VOC and VMP: Below is solar production analysis from the PV Calculator app, 30 degree roof tilt, -110 degree azimuth (facing South): Based on the above, I would be producing about 3.2kWh per day (1151 kWh per year, ~96kWh per month). Assuming 6 hours of PV production time per day. Based on my very loose average system consumption of 400w, I am using about 9.6kWh per day (excluding geysers, pumps, outbuildings, etc which are not on the system). It looks like I would therefore cover about 1/3 of my consumption with the PV I want to add. My questions: Are my assumptions that I can only do 2 x 475W panels in 2 x single panel strings correct? Are my calculations more or less correct? Is it it worth me adding just 2 panels to my setup given the production and consumption estimates above? Can I use a separate MPPT controller instead of the built-in one on the inverter, so that I can add more panels? Can I use a separate MPPT controller in conjunction with the built-in one? If I used the built-in MPPT controller, would the infamous "premature float" bug kill my LFP batteries prematurely? Am I wasting my time with this idea overall? The reputable solar installer who installed my system has quoted me just shy of R20 000 for the additional panel install, with COC, etc. This excludes the cost of the panels themselves which I will buy separately. The initial install cost about the same, and I bought the inverter and batteries myself. My goal is not to be self-sufficient here. It is merely to supplement my power demands, with the idea that I could charge my batteries off solar instead of Eskom (SBU mode), and perhaps cover my idle load (assuming and average of 9.6kWh per day). I also really like the idea of having some production capability in the event of an extended power outage (a bit of Mad Max thinking here 😄). Any opinions and advise are welcome, and thank you for reading this far.

@GVC did you ever finish this software or make it available?

Looks great! My eyes are happy. Thanks @Energy-Jason

I said "likely", not "definitely". I didn't check the inverter's specs in depth, so don't know if those parameters are adjustable on that model. The spec sheet doesn't rule out that they're NOT adjustable either. The battery type is however listed clearly in the spec sheet...

I suspect they do this to catch out the less knowledgeable people out there. I agree, it's bordering on dishonest.

Sure enough, I should RTFM 🫣

Sorry, I don't know anything about either of these, but the below might help you: https://www.solar-europe.co.za/wp-content/uploads/2021/09/Lux-Power-5KW-Off-Grid-SNA5000WPV-User-Manual.pdf https://powerforum.co.za/topic/15281-manual-for-nenergy-at48100/

You should start with providing your inverter and battery models and specs. It might also be a good idea to call your supplier for help.

There seems to be a fair amount of information on the internet, depending on what you search for. https://www.informit.com/articles/article.aspx?p=31105&seqNum=12 https://www.youtube.com/watch?v=Utxdioq4lNk https://www.velocitymicro.com/blog/top-10-signs-of-power-supply-failure/

🦗🦗

No problem. This post may be of use to you then: https://powerforum.co.za/topic/17359-diy-3kw-trolley-inverter-system/ I'm sure there are others on this forum and the internet.

Not really. Unless they are exhibiting problems or reporting errors, they are probably fine. Not really sure what you're looking for here...

I don't think so. Looks like they only come with SLA batteries, though you could likely replace them with LFP when they wear out and adjust your charge voltages on the on the inverter to suit them. Again, depending on your budget, but this might suit you for a LFP plug and play trolley system. You might outgrow this however, if you want to add more than your TV, Xbox, etc in future... so it depends on your plans. For something bigger, this would also work. Otherwise you can always buy everything separately and build yourself or get it installed, but a good installation will cost you.

Well I'll be damned. Thanks! I was looking at the error codes in the manual but didn't think of this!

I think it's fairly obvious - assume lead acid unless otherwise specified. They would be sure to tell you if it was LFP.

You didn't say what your budget is, quite important I think. Why not just get one of these? https://www.rctzone.co.za/rct-mp-t1000s Or the bigger version: https://www.rctzone.co.za/power-solutions/inverter/rct-mp-t2000s It will end up cheaper than building something similar up from parts, would probably look better and it covers your requirements. A friend of mine has a similar combo and it's a permanent fixture in his lounge, with the TV, computer and things always running through it.

See how it goes after a good charge on that Bosch charger if it has a desulphate setting. It sounds like your batteries have just reached EOL however. SLA/AGM batteries just tend to nosedive in terms of backup time when they get worn. If your batteries were used together in the same conditions, it makes sense that they would age in unison and both show symptoms at the same time.

@Coulomb maybe you know why this happens? I can send the PBEQA1/0 commands to activate/deactivate equalisation on my Synapse inverter. It accepts the commands and it begins to charge at the specified equalisation voltage (28.8 in my case), but the screen flashes an E9 error. Everything else appears fine and the error disappears when I deactivate equalisation. No errors or warnings are reported otherwise. By the way, I've established these Synapse 3.0V+ are rebranded VM-3000 machines (they report this model on a QMN reply).

You don't need a surge protector after your inverter. It's not going to play nice with square (modified) wave. Your computers are fine if they still power up. https://electronics.stackexchange.com/questions/10340/is-it-safe-to-use-surge-protector-with-12vdc-mobile-power-inverter

Hey @Gino i. nice project! FYI, your Github link is broken, not sure if you deleted the project... The axpert-pd software was one of the first things I tried when I got my inverter. Unfortunately their server side app puts my Pi into a bootloop, so for me it was unusable. I did speak to one of the devs at the time but they had no idea. Hence I moved on to the Manio project, which I've had to coerce to dump data to json via my shell scripts. I also don't use any database and my historical data is kept in json files. I limit them to 10k rows each, which is roughly 24 hours. What did you use to parse your data and draw your graphs? I must confess, although I put in a lot of time an effort into my monitoring solution, I've since moved on to SolPipLog using HomeHabit for monitoring on my phone. It has the advantage of being able to easily send commands, so I can switch modes, equalize on demand, change bulk and float voltages, etc from my phone. I do miss the graphs I was getting in my own homebrew solution, but I may still attempt to export the SolPipLog data to EMONCMS and load them as a webpage widget in HomeHabit.

Seems about right: See here: https://erikthiart.com/tools/calculate-battery-runtime-using-watts.php

Try a RS232 To USB converter.. Then install the software from the CD and see if it detects it.

@Roshe maybe obscure your home address on the screenshot...

I'd be very reluctant to open this can of worms again. As much as I would love to know the exact correct procedure, I've got the voltage readings so close now, that unless I run into other calibration issues in future (adding PV, charging issues), I'm going to let sleeping dogs lie. If anyone else on the forum is willing to experiment, maybe they can add some clarity to the process further. Thanks for all your helpful responses @Coulomb.