Sofar ME3000SP battery storage for solar and off-peak load shifting

[@artypete]

Good vid. I’ve just bought the 3600 version. It completely bypassed me that the Sofar has the option for timed mains charging at cheaper times - thanks for bringing that up, my energy contract runs out in October, so it might be worth looking at a flexible plan.

[@nhikoid]

Very professional and precise explanation. Been looking for a good video on the me3000sp for quite a while and here it is!. There are probably 000's of people in the UK who have strugggled to get MCS installers or have been let down and consequently installed their own max 3.68kw/g98 compliant system. ( like me ). Seems that the only legal way to extend beyond with more solar/wind is to feed DC from off grid controllers directly to the lead/acid bank and rely on the me3000sp + CT's to keep within the 3.68kw. That way you have the benefits of a 3.68kw DIY + storage + more kw's of additional solar/wind. Have you thought of doing that ( or anyone else out there ? ) . Or would this perhaps confuse/upset the me3000sp where it's taking ac coupled energy to feed the batteries while they're also being fed DC from additional solar/turbine controller?

[@AintBigAintClever]

With the right batteries I suspect you may be able to get away with it. The BMS controls whether or not the batteries will accept a charge. The BMS is what tells the inverter(s) what that charge level is. As long as the multiple inverters are on the load side of the BMS and not the battery side, they may play nice. You'd need to get clearance from the manufactuter, though (and hopefully be requesting the info regarding two devices from the same manufacturer).

[@nhikoid]

@@AintBigAintClever Wow, that was a quick reply. Thanks. Yes, I had consided lifepo4 but suspect that good old lead acid would be more tolerant. Will check with Sofar.

[@AintBigAintClever]

@@nhikoid the problem with lead acid is that unless you can get them ridiculously cheap (or free) they work out quite expensive when you look at how many kWh you can get through the pack over its entire lifetime. Depending on the battery construction you may not even get a thousand cycles out of it, compared to 6,000 for LiFePO4. Standby telecom batteries are meant to sit at about 50 volts or so constantly; they're not meant to be constantly cycled.

[@HighTechLab]

In the states, a company called CurrentConnected has this stuff down. Awesome inverters and batteries. Highly recommended

[@AintBigAintClever]

Wow, what a coincidence you commenting here. I looked up "lfp fire" on Google and your spike-through-the-cell video is what I landed on.

[@HighTechLab]

@@AintBigAintClever I’ve been watching your channel for probably 8 to 10 years now. Since photonic induction days.

[@AintBigAintClever]

@@HighTechLab you must be bored senseless by now then :D Some interesting bits on your channel, you've now gained a long-overdue sub :)

[@HighTechLab]

@@AintBigAintClever how cool

[@pdrg]

Great to join you on that journey, really interesting.

[@StuartPittaway]

Good video on the ME3000, I'm just doing an install of that unit myself. I've used FOGSTAR for supplying LIFEPO4 cells - they were in stock in the UK and actually cheaper than DOCAN from China!

[@AintBigAintClever]

That's interesting. When I look up the LF280Ks on Fogstar's wholesale website it's coming back at £2,600 inc VAT which is about £750 more than I paid for the cells from Docan. On the retail site even the B-grade LF280K are coming back at just under £2,400 inc VAT.

[@StuartPittaway]

@@AintBigAintClever ah, the prices must have jumped after USD rate. I had b grade for £1800 (16 cells)

[@edc1569]

I built a similar system, why the addition of the active balancer? I've not had an issue with the DOCAN cells with just the Seplos balancing.

[@AintBigAintClever]

Update 26th January 2023: I have so far received fifteen junk emails from third parties at the address used solely to deal with Seplos (see 14:16 in the video). Posts on diysolarforum suggest this is not a one-off occurrence. *DO NOT* fill in the enquiry form on the Seplos website unless you're happy receiving unsolicited emails from third parties as a result.

[@1stinsightpro101]

Great video quick question can you run that inverter as an off grid inverter only

[@AintBigAintClever]

ME3000SP is grid-tie only.

[@AutoCuePro]

Brilliant, informative video. I have just got a ME3000sp, I am confused re the WORK MODES. Is it the case that you choose to use just ONE work mode, IE: auto OR tou OR timed, or are all three interactive ?. My octopus tarriff is very expensive 16:00 - 19:00, and very cheap 04:00 - 07:00 and 13:00 - 16:00. So in a nut shell, if I charge my batteries in the early hours of the morning ( 04:00 - 07:00 off peak ) then at 10am the sun shine nicely, my PV's wont charge the batts as they are already charged from the grid. So yes, I could use the afternoon cheap rate ( 13:00 - 16:00 ) and that will charge the batts, IF the sun has not already done it. But how the do I get best use of my battery power to reduce PEAK charged grid power ( 16:00 - 19:00 ). If I have to choose just ONE of the modes available ( IE: auto OR tou OR timed ) I don't see how I can achieve what I want, and even if the modes are interactive, I cannot get my old brain around it. Thanks in advance for any help, David

[@AintBigAintClever]

The TOU mode (which overrides auto mode) is very flexible, so you can for example charge to 80% by 7:00, knowing that when the sun comes up any excess you're not using in the house will go into the battery. There's one firmware version which allows multiple TOU schedules in one day, so you could also program a top-up charge in that 13:00-16:00 as well. Some of this depends on the size of your battery, I manage to get enough between 2:00 and 6:00 to run the house for most of the day in winter. In summer I'll use a different TOU to put less in overnight as I'll be getting more from PV and I don't want to export any.

[@AutoCuePro]

@@AintBigAintClever HI Thanks for the advice, what really makes my brain hurt is, I really want to use my battery power to reduce or eliminate my grid usage between ( 16:00 and 19:00 ) as my rate for this peak time is double the standard rate. So in an ideal world I would charge 1st from solar, then if not fully charged, charge from off peak grid, but then use the batt power mainly in that 3 hours peak period when the price is double normal.

[@AutoCuePro]

@@AintBigAintClever I understand that TOU overrides Auto, BUT - If I select TIMED mode, does that mean that Auto and TOU are non used and irrelevant. ?

[@AintBigAintClever]

@@AutoCuePro Put a TOU schedule in to fully charge by 16:00 and you''re guaranteed to have plenty in the tank for the three hour expensive window, during which the ME3000SP will be doing its best to stop your meter turning.

[@AintBigAintClever]

@@AutoCuePro I don't know, I just use mine in Auto with a nightly TOU.

[@karltube99]

I've just bought a used one, and I'm more concerned about the threat of blackouts than most! So: When the ME3000 'Load' output (grid down) supply comes into play- it will drain the batteries (in your case red socket loads). Hence, no more benefit of solar. But if a grid tie PV inverter was also switched to this red socket...can the ME3000 'Load' deal with it, or be made to deal with it? I've seen small off grid inverters trick large grid tie inverters into working, but without a sufficient load they start to island themselves to death. Any thoughts?

[@AintBigAintClever]

I think the only way it would work would be if you can guarantee to be drawing more than the panels are putting out, possibly by using CTs on the panel inverter to monitor the ME3000's EPS output and configured with a "zero export" grid profile. I wouldn't try it as I wouldn't want to risk blowing the inverter.

[@chriswykes2319]

Do you need a specific cable for connecting the inverter to the bms or will a standard ethernet cable work? . Cheers

[@AintBigAintClever]

The ME3000 comes with the correct cable if new. If secondhand it may not but you can roll your own RJ10-RJ45 cable, which I did. www.boards.ie/discussion/comment/118426115

[@chriswykes2319]

Thanks

[@ollied1981]

Great video! Is the active balancer essential or does it just speed the balancing up?

[@AintBigAintClever]

Some say yes, some say no. It's a more efficient method of balancing than the passive balancing of the Seplos BMS.

[@ollied1981]

@@AintBigAintClever thanks for the reply. Did you have to change the software in the ME3000 to get the coms to work or only the BMS? Are they connected over rs485 or canbus?

[@AintBigAintClever]

@@ollied1981 No software change, the ME3000SP was already on 3.16 prior to changing to LifePO4. Changed the CAN protocol on the BMS to "Sofar", not much else. The active balancer doesn't communicate with anything, it just sits across the cells pushing power about if required to keep them in balance whatever the rest of the system is up to. Just a CANBUS link from BMS to ME3000SP.

[@ollied1981]

@@AintBigAintClever all sounds very doable! Thanks again :)

[@AintBigAintClever]

@@ollied1981 Doable and well worth it when you work out the cost per cycle of imported LFP cells, especially important if also using the pack as an off-peak load shifter. Hardest job is probably getting hold of a cheap ME3000SP now as they seem to be in short supply. Plenty of charlatans about when it comes to battery importing, but Jenny's one of the good ones hence the link in the video description.

[@mattcole6230]

Brilliant video this. I've been looking at this inverter to go with my existing grid tied system and pylontech batteries. Hoping its almost plug and play! I've also got an EV which charges on night tarrif. I assume the inverter can be timed to top up the battery even when simultaneously charging my EV? I assume it can which would be ideal for me.

[@AintBigAintClever]

Yeah, it's pretty-much plug and play, the wiring is basic for someone competent to do so, it just sits hardwired into its own circuit (or an existing circuit as long as it's appropriately breakered). As long as you tell the ME3000 to do a time-of-use charge all the time the EV is likely to be charging up (e.g. the entire off-peak period) the EV won't slurp from it, leaving the ME3000 to do the house during peak rate. That's how mine's set up, unless I pause the charging to have a shower (16A charge plus 13A charge plus other house odds and sods plus a 30A shower, all on a 60A service fuse? I'd rather not :D

[@mattcole6230]

@AintBigAintClever smashing! Hoping to get going with my setup in the next few weeks.

[@justindavid571]

Excellent video. And very informative, thank you. I think this is the way I'm going to go, as my growatt inverter on my pv array isn't battery ready. Just one question, is it essential (or just wise) the MS3000 inverter needs to communicate with the battery? I have a couple of LG chem ESS packs I was going to use and the BMS' I've ordered for them don't have comms ports 😒

[@AintBigAintClever]

Without comms it's relying on battery voltage to figure out what's going on, so I'm not sure how well it would fare.

[@justindavid571]

@@AintBigAintClever Thanks for taking the time to answer . I was thinking about this after I posted. I’m putting the batteries outside in a fire rated enclosure so I definitely want some decent comms, especially temperature readings.Guess I’ll use the BMS I’ve bought already for another project!

[@AintBigAintClever]

@@justindavid571 worth putting a tubular heater in the enclosure as well, along with a frost thermostat to keep it above freezing. I've got the whole lot in my shed which has a tubular heater but the activity of the inverter and batteries takes the edge off in there so I think it'll only come on when I spin the dial to see what the temperature is in there.

[@colinm6251]

Hi I have the same inverter it has the discharge option but doesn't discharge any ideas? Thanks

[@AintBigAintClever]

As in the forced discharge regardless, dumping out to the grid if necessary? No idea (I can see its use if you have a generous SEG tariff and cheap off-peak). Try asking at facebook.com/groups/2477195449252168

[@iansummerfield]

mine uses cheap rate to charge overnight but then sends it back to the grid in the morning, do you know why?!

[@AintBigAintClever]

Loads of it or just a couple of watts either way? Have you frozen your CT clamp settings so it doesn't confuse import with export and start feeding out?

[@CrAzY-tt7dw]

Hi, sorry new to this but loved the video, I have the same setup inverter and batteries. I can see you have wired up a plug (red one in the video) to the EPS, have you taken a cable from the EPS port straight to the red plug e.g normal 3 core (L,N,G)? Or have you a bunch of fuses etc or is this wired back to the house. Interested in doing the same but not sure on how this is wired, hope you can show more :)

[@AintBigAintClever]

3 core from the inverter's EPS output straight to the red socket.

[@Pete-detail]

@@AintBigAintClever brilliant video. I've had my sofar3000me with 9.6k pylontech for a number of years now without critical load due to the Manuel stating that I needed a special board . Your guide is the first I've seen that actually shows I can wire a plug directly to the critical load EPS. Thank you so much.

[@AintBigAintClever]

@@Pete-detail if you want a briefly-interruptible power supply you can fit a DPCO contactor with 240V coil. Wire it with NC pins to the mains, NO and coil pins to the EPS output and COM pins to the protected load. If you just want something that's quicker and cleaner than dragging out a generator, EPS straight to a socket :)

[@МихаилЗатерка-щ5ы]

Hello. What is real efficiency of the inverter working from the batteries? For example for UPS Eaton "paper" efficiency is about 92% working from the batteries. But real efficiency is 50-70% So in 1550 VA UPS you take 432VA battery, load it 200W and get 54 min of run time. Heat disposition for 1500VA UPS is about 200W, for 3300VA it is 800W!!!

[@AintBigAintClever]

It's difficult to calculate. The DC side efficiency is about 97%, based on a day going from 20% to 90% and back down to 20%. The AC side is trickier to determine as some of the day's load will have been drawn from the mains, either during the charge (car charging at the same time as the inverter), excess (running a shower) or when the battery is discharged (beginning/end of the day), all of which will skew the figure upwards. On top of that you've got PV generation, some of which may be going into the battery (although not much at this time of year). I've run a few calculations and it seems to come out at around the 82-85% mark. That's done by totting up the amount of power consumed by the house while the system is either discharged or charging at the start of the day, plus the amount of power purchased throughout the day once the inverter starts, and lopping this total off the total consumption figures to determine the bit that flowed in and back out through the inverter.

[@МихаилЗатерка-щ5ы]

@@AintBigAintClever according to the specs there is no inner fun, so heat desposition is the smallest than any other dc ac inverter.

[@AintBigAintClever]

@@МихаилЗатерка-щ5ы yes, they're fanless, although some people add fans to increase airflow if they're in a warm environment. The rear heatsink can get hot if it's running for a long time at full power, but with the batteries being separate it's less of an issue. Over a full charge lasting about 4 hours the heatsink rises from 19°C to 54°C, the battery pack from 16°C to 23°C.

[@icyfox2011]

That's a neat system you have there! Do you have any experience of putting the inverter in passive mode and controlling it remotely? I'm thinking of building a similar system, without solar, just to cut down the energy cost by shifting the load to the "cheap" night hours. In passive mode, through Sofar2mqtt it should be possible to remotely tell the inverter to start charging/discharging at set rates. I wonder, if I set the discharge rate to let's say 2000W, will any excess get exported to the grid if the load is less than 2000W, or is the value a maximum rate that the inverter will stay below? Also, if I want to completely cover the whole house consumption in a three-phase house, that would require installing a CT sensor on each phase, L1, L2 and L3, wouldn't it? Will the ME3000SP sum the readings and ramp up its single phase output to cover for the other phases (up to 3 KW)? That would be ideal, thanks to the net metering we have.

[@AintBigAintClever]

I don't, but check out facebook.com/groups/2477195449252168 When discharging mine only supplies what's needed by the load. It can be put into a discharge-regardless mode but I think that's for testing. If you wanted to export single phase to match three phase usage then that's definitely going to require additional equipment to add the three out-of-phase CT readings together and provide a combined, fake figure back to the inverter. Big can o'worms there.

[@icyfox2011]

@@AintBigAintClever I think I found the answer to my question, why did I not read Sofar's website before... On their website it says: "It has 4 CT input ports to easily measure the PV generation power of any PV inverter brand on site, as well as the 3-phase power flow to and from the grid." So it would indeed seem that the inverter can match the total consumption over three phases as long as it's below 3KW.

[@AintBigAintClever]

@@icyfox2011 you'd probably be best contacting Sofar to find out whether the information is used by the inverter or just for display. For single-phase CTa is used, plus CTpv to monitor any solar production. CTb and CTc are on the bottom of the unit but aren't mentioned in the English version of the manual. A German one found online mentions them, translated as "Mount current transformer (CT). Open the converter and mount and connect around the current phase L1=CTa, L2=CTb, L3=CTc.CTpv=supply line from the inverter (optional, this terminal is only used to display the current production.)Caution CTa must be on the same phase as the 230V AC supply of the ME3000."

[@chriswykes2319]

Great video thats the exact same setup I have ordered 😁😁. Where did you get the sofar protocol software for the the bms ?

[@AintBigAintClever]

It was one of the on-screen options within the Seplos software, possibly in the CAN pull-down top-right you'll see at 21:01.

[@chriswykes2319]

@@AintBigAintClever thanks for that. I was under the impression that I needed to flash a firmware for the sofar integration.wasnt aware it was already in the program. Cheers for that 👍

[@AintBigAintClever]

@@chriswykes2319 I was going to suggest looking for the "Sofar Solar Inverter - Remote Control & Smart Home Integration" group on Facebook, but I see you joined last week :)

[@AnthonyLepecha]

Do you know what happens if the grid CT is disconnected?

[@AintBigAintClever]

The perceived power consumption of the house will fall to zero, so the power delivered by the ME3000 will also fall to zero.

[@AnthonyLepecha]

@@AintBigAintClever that would make sense but when testing the unit it does not do that

[@intelmacs]

If you don’t mind me asking, how much did the lifepo4 cells cost?

[@AintBigAintClever]

It was £1850 including shipping (Delivery Duty Paid) but the price is quoted in US dollars so will fluctuate depending on the exchange rate used by your bank at the time of placing the order.

[@jam99]

Very nice. Well done for all the hard work. A shame you couldn't have stuck with old batteries but I can see why that is not going to be an option for most people (I think Powervault do a recycled EV home battery - access to these recycled EV batteries for DIY packs may become a thing as more EVs mature but I am not sure many companies will want to take the fire liability risk for over the counter cell sales). I think an EV was a good solution for me - batteries came included! But there is the limitation of the minimum 1.4kW charge power because of the EV charging protocol, and the car has to be at home when the Sun is out. My solar diverter (relatively cheap iBoost bought many years ago) for water heating uses the excess solar when below 1.4kW and for when the EV is away from home though I could do with a bigger immersion tank. It's only a good battery solution for a vehicle that spends most of the middle of the day at home like those who work at home and, of course, you can't pull the power back out of most EVs so most efficient when you use at least as much as you store, but even the smallest EVs I think now have battery capacities approaching about 40Kwh. I was doing things manually with a variable granny charger but now have a Zappi installed with three CTs which appears to be working brilliantly so far and automatically manages things sensibly with the car plugged in all the time it is home. The only occasional problem is overvolts on the mains because our DNO gives us really high mains that occasionally touches 258V. And I could really do with the lichen being taken off my PVs.

[@AintBigAintClever]

Have you raised this as an issue with the DNO? European supply voltage is supposed to be 230V +10% -6%, so 216.2 to 253 volts.

[@jam99]

@@AintBigAintClever Thanks. I have been meaning to for a while, on behalf of the whole village but nobody else has raised it locally to my knowledge. I just want to check a couple of neighbours' supplies first to make sure it is not just me (can't see why it would be). I haven't ruled out correlation with solar; it seems to fluctuate a lot. Do you know of any cheap(ish) standalone plug in gadgets to log a record over time?

[@AintBigAintClever]

@@jam99 you missed a LEM Analyst 2050 which went for £100 on eBay a fortnight ago. I picked up my rebadged LEM Analyst 3QC for I think £230 because (a) the listing didn't have much info, (b) the version being sold (Minipa ET-5060C) was pretty unheard of over here and (c) the listing ended at 4am so nobody around to snipe the auction. It's basically a Fluke 1735 with more bells and whistles.

[@jam99]

@@AintBigAintClever Cheers! I shall look out for one. At home I am using an APC SmartUPS with PowerChute to record but it is bound to miss the extremes and I can't use it in someone else's house. Better than nothing though. Just don't want to get fobbed off by the DNO. However, I expect they will have some excuse up their sleeve. We'll see.

[@AintBigAintClever]

@@jam99 ooo, good call on using the SmartUPS. If it's got a SmartSlot then the cards log data every 10 minutes with maximum and minimum voltage encountered during that period.

[@jacopo.scarpellini]

Hi, I just bought the same inverter which I’ll be connecting to a DIY LifePO4 280Ah 48V pack I have bought a JBD BMS for just over £100, but I think it won’t be able to communicate with the inverter (doesn’t have RS485). Do you think I should return it and buy the BMS you have? Was it easy to make it talk to the Sofar inverter?

[@AintBigAintClever]

Does the JBD support CANBUS? That's how mine's connected.

[@jacopo.scarpellini]

@@AintBigAintClever no, I don’t think so; what bms do you have?

[@AintBigAintClever]

@@jacopo.scarpellini the Seplos one in the video.

[@jacopo.scarpellini]

@@AintBigAintClever can you point me to a place to buy it?

[@AintBigAintClever]

@@jacopo.scarpellini it's already in the video description.

[@jacopo.scarpellini]

Hi, what have you set the charging power to? I’ve set mine to 3000W but only 45A are going into the battery, meaning I can’t charge it in only 4 hours

[@AintBigAintClever]

Mine's set to 3000W but is topping out at 57A, with most of the charge being at about 53A. That's between 2.85kW and 2.9kW for mine as it's a 16-cell, 51.2V pack. I expect the BMS will be calling the shots in your case, it'd be worth seeing what can be configured on it. Also check that it's constantly doing 45A and this isn't just a charge current encountered when the battery is at a very high or very low state of charge. At the moment mine is cut off at 20% and does a nightly to 92%.

[@jacopo.scarpellini]

@@AintBigAintClever it was 45.68A at 30% SoC with total voltage 53.82V; that’s 2458W; I also suspect it’s the BMS (Seplos)

[@jacopo.scarpellini]

Also I just noticed that if I go to ‘System information’ it shows ‘Max charge (A): BMS: 50A Set: 65A’ Apparently it thinks the BMS is limited to 50A but there isn’t such a parameter in the Seplos BMS

[@AintBigAintClever]

I'll take a look at mine later this afternoon as I want to pull some logs from it. I just noticed that 20% seems to be dipping below 49V, possibly since I adjusted the top-end to 92% instead of 90%.

[@AintBigAintClever]

@@jacopo.scarpellini try the Single BMS 1.0C setting, details here: diysolarforum.com/threads/seplos-can-bus-rs485-48v-200a-8s-16s-bms.20051/page-46#post-672337 Also of note, the inverter reports a real-time value from the BMS, you'll see it throttle at the top-end of the charge if any cells hit the overvoltage threshold. Mine's currently bouncing off the 9 amp threshold as I'm topping off the pack.

[@JohnSmith-vz8pc]

10:20 You're kidding?? 😲 2022 and it has no non-volatile memory for the settings!??

[@AintBigAintClever]

It has NVRAM otherwise it would lose everything on a power cycle, but if you go in to change battery settings the existing settings get cleared.

[@JohnSmith-vz8pc]

Use LiPo cells instead. you can cycle them more, and 2x DoD. I can sell you 20Ah (prismatic EiG) cells for £15 each. plus busbars, with I can help you with.

[@AintBigAintClever]

That works out almost twice as much as the 280Ah x 51.2V LiFePO4 pack I built for £1800, plus I wouldn't trust LiPo not to burst into flames and take my shed with them.

[@Agavarc]

High power battery bank, on carpet, surrounded by wood. Not the best place for storage 😜

[@AintBigAintClever]

I wondered how long before someone picked up on that :D The alternative would be to put the pack in the house (nope) or outdoors (also nope, they can't charge when freezing and I don't want them pinched). The shed is cheaper to rebuild than the garage (also carpeted). The wood should fare better than the plastic crates these batteries also get packed in in home setups, anyway. Also, LiFePO4 are safer than other lithium-based battery chemistries as if you short them out they'll sooner melt their terminals away than catch fire.