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It might work the way you described it. Each inverter synchronizes to the phase it is connected to. However if the grid fails (load shedding) they will no longer have a 3 phase reference and output non synchronized phases. Your 3 phase geyser would work in star connection but not well in delta. 3 phase motors would probably have problems.

Since your system has no grid connection settings 12 and 13 have no meaning. These determine when the system should switch to grid and recharge the batteries from grid when battery voltage is low and switch back to battery (back-to-discharge) mode at the set higher voltage. If there is no grid present the system will not switch. Make sure all possible automatic restarts are enabled. Low battery cut off (29) at 45V seams reasonable but check with the battery specs. Setting 16 "charging source priority" should be set to OSO (solar only). But if you want to recharge from a geni you need to set it to CSO.

Hi all, my house is not ideally oriented for solar harvesting. It has a large 26° roof slope oriented 60° to Northwest (300°) and a small slope Northeast (30°). I installed 4 arrays (3s) on the large Northwest slope and one array on the Northeast slope. So I harvest some in late morning from the Northeast slope (few in winter) and the main part starting about 13h from the Northwest slope. The 26° tilt is too slow for winter sun, it should be 45°. But that would require important support structure and expose the panels to the winds. So I decided to install an array vertically on my windowless Northeast face. The result is amazing. I get almost full power from them from about 09h in the morning until 13h. It is electrically in parallel connected with the Northeast roof mounted. During these winter months the sun remains low therefor shines at a good angle on the vertical panels but less favorable on the roof panels. On the other hand being low the solar radiation is weakened by having a longer pass trough the atmosphere. As the season goes on the sun gets higher, thus the radiation angle becomes less favorable but on the other hand the radiation becomes more intensive. I am amazed. "Decoration" of my Northeast face. Looks almost like windows. The small door on the left bottom is the access to the shack where the inverters and batteries are installed. If someone is interested in the DIY mounting structure just let me know, I'll be happy to share.

It is my assessment that packs internal resistance differences are far greater than cable length differences at 25mm² or even 16mm². My newest pack, same type, same manufacturer, is connected last in row, thus has the longest cabling yet it shows the highest charge and discharge currents. I presume it has significantly lower internal resistance than the others probably due to improved manufacturing procedures. A propo equalizing: I observed that Packs do equalize during charging when reaching full charge. This is due to the physics of batteries and Ohms law.

I have set battery mode to USE and set all parameters to battery specifications. As the specs on my batteries say the BMS cut off voltage is 40.5V I set 29 to 42V.

Welcome to the forum! It looks like your inverter is a genuine or clone Voltronic. Try setting 01 to SbU. I would recommend setting 05 (battry type) to USE. Then set 12, 13, 26, 27 and 29 to battery specifications.

I don't know about Deye, but Voltronics rebrands require that parallel inverters must be using one and the same battery. You might add battery packs of different brands respecting the requirements that TaliaB outlined.

Well, I could also sing such a song. I installed the 4th pack of LEOCH 48100 TB a year later than the previous ones. Its BMS has soon gone out of sync although the currents are reasonable, considering it has significantly lower internal resistance. I do not attach too much importance to it as to me the pack voltage is the important reading. Also the individual cell voltage readings look normal, only one cell shows consistently a few mV higher than the others, but within tolerable range. The inverters manage the charging on the base of battery voltage and do it well. All packs show still 100% SOH.

Why not just monitor with the BMS? I installed some 7 meter of RS485 cable to my office, connected it with an adapter to USB of my laptop. I monitor with PmodbusToos. It can also be done with WiFi.

Could it be the "back to utility bypass" voltage, Nr 12 in Voltronic rebrands settings? And "battery re discharge voltage" would be the "back to battery mode", setting Nr 13. I set 12 to 47V, 13 to 50V (15 cells packs).

Skin effect is a phenomena of high frequency alternating currents. On batteries we are dealing with DC (direct current). And - to prevent skin effect with high frequency on stranded cables, each strand would have to be insulated individually. (Radio technology)

I found them! At Herholdts in Bloemfontein: JAM60S20-375W/MR 6,00 EA R1 023,00 R6 138,00 (+VAT) JA Solar Black Framed White back Module 120 cel +shipping R350.

Most of these appliances are driven by induction motors. By nature these motors draw up to 5 times rated current for startup if the terminal voltage is maintained. If you measure less it's due to voltage drop in the feeding line caused by the high current. This applies also to fridges and freezers.

Brave performance My system consists of 2 Synergji/Axpert MKS5K 5kW off grid inverters in parallel, total 10kW. I have a total of 400Ah LFP battery and some 4kW solar panels. Lately the municipality changed tariffs and introduced a base charge depending on the max power allowance. In order to save money I had it reduced from default 60A to 45A. That amounts to 10.35kW. This function is built into the prepaid meter. One day at dinner cooking time the cooks managed to draw close to 6kW while accidentally the geyser ran with 3kW. The system normally runs off grid and the batteries were well charged. However the heavy load of close to 9kW pulled the battery voltage down, the kettle effect, below 47V where my setting for "back to grid" is. So the inverters switched to grid bypass mode. So far so good, however then the battery chargers kicked in with 2kW. The total charge was then close to 11kW, off limit for the meter that tripped. With the grid power cut off the inverters acted like an UPS and switched again to battery mode. After a while the meter automatically resumed power delivery. The inverters recognized the presence of grid power and with battery voltage below 47V switched back to grid bypass mode. The game started over a couple of times until I turned off the geyser. Conclusion is that the inverter system has well performed, there was no blackout in the house. And we have to watch the geyser being turned off during cooking.

So far good experience (4y) with Synerji/Axpert, true Voltronic rebrands, sold by Herholds. They have outlets all over the country. Recommend the MKS 5K, 5kW off grid with 4kW MPPT.

Important is they must be of same chemistry (same type) and the same number of cells. However they may have different Ah size.

I have 2 Axpert/Synerji MKS 5K inverters in parallel. On one are 9 335W 72 cells panels 3s3p connected that deliver 3+kW. The MPPT has 4kW rating. On the other I have one array of 3 345W 60 cells panels 3s connected. I would like to upgrade with a second array of 3 panels. As one can only parallel panels of same number of cells with same operating voltage I'm on the surch for 60 cells panels. I have inquired all solar outlets in the region with no success. Is there anyone that can help me to find such panels? Perhaps someone wants to get rid of such? The actual panels are Canadian Solar CS3L-345P. 32.8V, Voc 39.8V. Thank you in advance.

Thanks you for all your reporting. However the differences of internal resistance between packs are likely to be far greater than differences in lead lengths. My newest pack is wired at the end of the packs wiring, has the longest leads, yet draws the highest currents due to its lower internal resistance.

As I have written in other posts, I have 4 LEOCH 48100TB packs with uneven internal resistance. In particular the last one purchased has significantly lower resistance that results in higher charge and discharge currents. The BMS report SoC accordingly, however the newest one reports havoc. However I observed that parallel connected packs equalize themselves when reaching full charge. This is a natural phenomena given by the physics of the batteries. That is as long as there is no fault in any cell. So don't worry, just charge them all together to bulk charge voltage and then lover to floating voltage. The correctly set inverters do it themselves. Don't get disturbed by the BMS SoC reporting. I trust the battery voltage more than the BMS. (Read "Are BMS reliable?")

Battery heating is provoked by high currents due to their internal resistance. 1C currents are poison for that reason. I conceived my system to remain under normal circumstances within 0.2C, with exceptions up to 0.4C. Ambient temperatures that human beings can support are OK for batteries. Perhaps she rather invests in an additional pack to lover the shared currents than in an airco.

I have not digged yet into EV technology. But it is my understanding that EVs do store regenerative braking energy in the batteries of actual technology. Am I wrong? The actual batteries are fully capable to take this recharging power. The breaking power is however limited by the power capacity of the motors.

I'm not convinced with this. First, capacitors do not have electrodes but plates. Second, carbon is a material with high electric resistance. That creates high losses at high currents. Then - the claim for ultra rapid recharging is an illusion because it would require ultra high power at size of a power station to recharge i.e. a car battery. That simply is not available at service stations. Let alone the limited current capacity of charging cables and plugs.

Are they capacitors or are they chemical cells? If the later why talk about capacitors?

Right. It's not the size of the battery that dictates the cable size, it's the load. If you have 10kW inverter it can draw at maximum 200A at peak load. But that happens most likely seldom if at all and for very short time. The mean load in my household with electric cooking is around 3 to 4kW with peaks up to 6kW. My batteries are happy with 25mm² cables.

Thank you for your considerations. That total discharge already happened accidentally together with all packs. Noting changed. Some time ago I observed when its SoC suddenly switched from about 60% to almost 100% while approaching full charge voltage. But that didn't happen again. It looks like the SoC accounting is screwed up. I just don't pay attention to it, the inverters act on battery voltage. And the pack currents tell what's happening.