Calvin

You may need to be more aggressive with your pricing. Right here on PowerForum Store you can get a Deyness 14.3 kWh LFP with 10 year warranty for R37 375. Dyness PowerBrick 14.336kWh Lithium Battery

Yes. You would be using about 50% of the yield strength of the rod (assuming grade 3.6 steel), so in theory it would be (just) OK. However, depending on the length of the rod, it will twist significantly as you tighten it. I would recommend an 8mm rod. Another useful calculator: Torque and Preload Calculator | Bossard South Africa

You can use an online calculator to find the clamping force (Bolt Torque, Axial Clamp Force, Bolt Diameter Calculator) That will tell you that 4 x 8mm screws tightened to a torque of 1.2Nm will generate about 3000N (about 300kg force)

Did you take him up on the offer to send you some cells? Reason I ask: an acquaintance of mine has recently bought four similar units (WEST Summit Series 6.6kWh Supercapacitor Storage Module 48v | TYTON Technologies.) The link is the CEO - the same Larry "Chip" Seibert who was a co-founder and CEO of Kilowatt Labs is the co-founder and CEO of Wright Energy Storage Technologies. Different name, same scam. My friend is in denial - nobody likes to admit that they have been scammed. I am trying to convince her to demand her (lots of) money back - any additional evidence you have would assist. I do notice that Arvio no longer describe their "zero degradation after 14000 cycles" batteries as capacitors - they now call them Titan and admit that they are LTO. (Kilowatt Labs still list Avrio as a reseller, so presumably it is the same item)

Correct. The log covers only the last month or so. However, see the totals at the beginning (from the STAT command) Pwr OV Times : 46 (In Pylon speak, a PWR is what we call a battery pack (15 cells) and a BAT is a cell) Pack OV is at 54V for these batteries.

It seems to me that both Pylontech and Voltronics are to blame. Pylontech for requesting voltages that are too high (in the real world, where 2nd rate manufacturers implement poor control algorithms that overshoot) and Voltronics for being such a 2nd rate inverter manufacturer. You will probably find the other batteries are all in advanced stages of degradation. Consider setting battery type to USE and max charge voltage to the lowest that still gets you to 100% - my Pylons work well at 52.6V. Also consider setting the float voltage down to about 50.5V. It will mean that your SOC will drop to about 99.5% as soon as the batteries are full, but it will greatly enhance their lifespan. Of course using an Axpert means that your inverter cannot be relied on to correctly switch to float, unless you are running a version of @Coulomb's patched firmware.

An interesting topic: It appears that Deye has locked Deye branded "grey import" inverters in countries where they have a rebranded alternative: SolArk in USA, Inverex in Pakistam and Sunsynk in UK. Somewhere in the 100-page thread linked by @P1000 Sunsynk in South Africa is also mentioned. This raises flags about potential risks: a. Buying grey imports b. Giving access to your inverter to somebody in China who can lock it without any form of due process. Key take-away: if you are running a Deye that you suspect could be a "grey" import, do not use the dongle to connect to their cloud service!

Do NOT do this. The Kodak OG5.48 Plus has a 145V max SCC. You ideally should wire these 2S. Not so easy when you have 9 panels...

I agree with you, great stuff. I have used it in-wall, under slab and for ceilings. My only gripe is with the ceilings: it can be very noisy. A moth or even a fly flapping against it makes a lot more noise than traditional gypsum ceilings. I am actually considering putting in a noise insulation layer below the isoboard in the bedrooms.

The answer depends on whether the water in the pool is in fact warmer than the surrounding soil. If your pool is heated (with say a heat pump) then the water will be warm relative to the surrounding soil and the isoboard will slow down the dissipation of heat into the soil. If, on the other hand, the pool is not heated it is very likely to be colder than the surrounding soil (due to evaporative cooling, the magnitude of which will depend mainly on RH and wind). In that case the isoboard will slow down the heating of the pool water from the surrounding soil.

There is no point in "balancing" - the fact that they are connected in parallel means that they are all already at the same voltage. The balancing you read about is what is done when adding new batteries to your stack. (To add to the confusion, there is also cell balancing, but that is handled by the internal balancer) You could get Batteryview and connect to the console port of the dud battery. You will likely see that there is one cell that is stuck at 33% charge (the Pylontech reports the SOC of the battery as that of the lowest cell, not the average). Irrespective of what you learn from Batteryview, your next step should probably be to remove the bad battery and send it back to your supplier, hopefully for a warranty claim (assuming it is still covered). Once a battery has a bad cell there is very little that can be done - the pouch cells in these batteries are not readily available, and even if they were replacing them is not a trivial task.

All the heat rejected by your inverter (whether through convection or radiation) will end up heating your house. The question is: is this significant? That depend on the efficiency of your inverter(s) and the amount of power you use. I used to run 3 Axpert Kings in parallel and their poor efficiency meant that I had losses around 10%. That means 1kW of heat if your loads are 10kW - a lot of extra heat in summer, quite nice in winter... (used the inverter room to dry washing in the wet Cape winters...) I now run a 16kW Deye and the losses are less than half at the same loads. So, if you are using just a few kilowatts with a good inverter the heating will at most be only a few hundred watts - similar to a couple of old incandescent light bulbs. Nothing to be too worried about.

I love a really well reasoned intellectual discussion. Guess I will have to look elsewhere.

UPS port is the same as load port or essential loads. Power is sourced from PV, grid and/or battery. If you do not have a battery then with these inverters you need your loads to be connected to the grid/non-essential port, not the load (UPS/essential loads) port. My setup is like you describe (all loads on load port, only grid on grid port, with batteries) and everything works exactly as one would expect/hope. The only thing I cannot comment on is the export function - I do not sell back to the grid.

Agree 100% - this plan is certainly not new, and I have not seen any evidence that it is designed to "punish solar users". My understanding is that ESKOM is behind international best practice in their slow transition to fixed monthly changes. My own example: a few neighbours and I share a long 11kV line that is often damaged during storms. I cancelled my Landrate account 5 years ago (about R5000 per month fixed fee) and went with solar and a prepaid connection (as essentially a no-hassle generator). Works wonderfully, but my ESKOM usage is now about R2000 p.a. - certainly not enough to cover my share of even their maintenance costs. You are all cross-subsidising me (thank you) but I would have thought that you would welcome ESKOM's efforts to level the playing field.

Are these batteries all exactly the same age? The reason for asking is that the cycle counts are very different. If they are the same age it could be due to unequal cable lengths. Are they connected correctly - positive and negative at opposite ends of the pack? I run 10 pylons and never see difference like these....

PBMS is for Pace BMS - for Pylontech use BatteryView. (available in the download section)

Fair enough - I was thinking of my own preference which is to have a spare on-site, or I would simply buy another one if needed. Waiting weeks for repairs is clearly not an option if you are off grid.

@Toxxyc I have a similar setup to yours: a smallholding, used to be on Landrate 3 phase 25kW supply wanted to get off grid. One thing to consider: ESKOM has a product called LandLight: a single phase 20 or 60A pre-paid with no fixed charges (for now anyway..). The unit cost is high (but less than diesel), without the noise and hassle. I converted to this and have never run my generator... I ran 3 Axpert Kings in parallel for 5 years and have had a thousand issues. I have recently upgraded to a 16kW Deye and it really is worth the extra money. One great thing about the Sunsynk/Deye option for off grid is that you can limit the power it takes from the generator (and from the grid if you e.g. run a 20A Landlight supply). The Voltonics inverters (Axpert/Mecer/Kodak/RCT etc) do not have that ability - the generator also supports the loads. As loads vary, the generator speed changes resulting in the inverter rejecting the input. So you need a generator not only capable of supporting all your loads, but also able to handle sudden variations in the load. (you will find many threads on this forum discussing this issue) I used this logic with my 3 Axpert Kings, but it did not really work well for me. Whenever one developed a problem (there were many) the whole lot shut down and needed an electrician to disconnect / reconnect a new inverter before it would start up again. 3 points of failure meant 3 times more interruptions.... I now use one of my old Kings as an offline UPS to see me through if the Deye should develop a problem.

When USR (AGM) is selected there is by definition no "comms". the cable may or may not be the right one, but the inverter will not attempt to use it. It will use the manually specified voltages. Looking at the settings in your first post (56.4V charge), the inverter is set up for a 16 cell battery. The combination of the above 2 items is lethal. Your battery has been systematically overcharged - that would explain its inability to now hold a charge.

It is quite simple: The load port is actually the UPS port - it needs a battery to be functional. You need all your loads to be connected to the grid port, which is both an input and an output port. From Sunsynk training manual: IMPORTANT: When using our inverter without batteries, you can only connect to the grid connection, which is both an input and output, similar to a standard string inverter. Many users misunderstand this point and mistakenly connect the outputs to the ‘LOAD’ and the input to the ‘GRID’ connection when there are no batteries. This is simply wrong, and the inverter will not function correctly. In Figure 4 and Figure 5, you can see a ‘GRID’ input and a ‘LOAD’ input. Do not think that the ‘GRID’ is the input and the ‘LOAD’ connection is the output. The ‘GRID’ is an input and an output, and the ‘LOAD’ is a UPS. Therefore, when you have batteries, you will connect only essential loads such as lights, security devices, routers, and computers to the ‘LOAD’ connection and, with the ‘GRID’ connection, you will connect the nonessential loads such as most sockets, air conditioning, heaters, etc. However, if you do not have batteries, you will not use the ‘LOAD’ connection. You must connect all your loads to the GRID input.

This is no longer strictly correct. I have 3 Kings in parallel and the Dynamic Charge Control not only does not work but causes wrong data - I reported the symptoms to @Coulomb some time ago. Having said that, all the other features work very well, exactly as advertised. Great improvement over the normal firmware.

@JT1 I am obviously not expressing myself clearly - let me try again: Of course the batteries in each inverter pack are at approximately the same voltage - they are after all connected in parallel. The busbar I am talking about would be there to connect all the different packs together, so that all the packs are also at the same voltage. You need one large battery pack for your 4 paralleled inverters, not 4 separate ones at potentially different voltages.

Maybe a little harsh: they did replace 2 batteries under warranty, despite them being installed incorrectly.

Except, if you look at the last picture in his first post, there was a 0.7V difference across the 4 batteries shown with very little current flowing. Difficult to imagine if they are all connected in parallel.