Nonlinear

Done. Good luck and let us know how it goes.

I'm surprised no-one has replied. I'm not an expert but here goes: A1: There is software from Pylontech called batteryview which you can use. It is linked in various places here and in the AEVA forums, so a quick search should reveal it, see A3 for more. A2: As far as I am aware the setting is not in ESS but rather in the GX device (Cerbo, CCGX etc.), you can set it under alarms and you can also disable audible feedback, you cannot disable the alarm on the Multiplus/Quattro itself (i.e. if an LED is flashing it will continue to do so). A3. As per above use batteryview; it is a windows application. If you are a confident Linux user then you could also open a console to the battery via serial and query just about anything. The same may be possible under Windows but I can't give much guidance in that regard.

Hi Dewald, Thanks for the reply. I'm a little concerned that these may be clone inverters as I need to run on @Coulomb and @weber firmware and the chances are good that it will brick the unit if I try to flash it and it is a clone. Looking at the label I would say it almost looks like a Voltronic but reading on the AEVA forum it seems these may be clones. Where did you get these?

Item Wanted: Mecer SOL-I-AX-5p or equivalent RCT Packaging Essential: No Desired Age: 3 years or less Location: Centurion Willing to accept a shipped item: Prefer to pick up within reasonable distance (<500km) Ballpark/Budget Amount: R10k Must have a parallel kit. Am willing to take two. These are the 5kW/5kVA units (i.e PF1.0) with an 80A MPPT with max open circuit voltage of 145V. Will also consider the equivalent Axpert King (will need to be two though).

I have a set of Mecer Axperts in parallel and am slowly migrating to the blue side. I still retain a keen interest in the Axperts because I maintain they are acceptable for most people who run them within their capabilities. Also, having lived with them for a number of years I have experienced the highs and the lows of owning Axperts.

I am quite aware of that, I was hoping to use that as a gentle introduction to the topic.

What is the firmware revision?

It was a struggle (to put it mildly). For bonus points I can confirm I used the regulation SANS cable too which was even harder to do. Correct. The problem though is small differences can have a large impact when resistance is already low. So, for example, with a very large (say 16mm2) cable the resistance on each could be very low, about 0.02Ohm. Now a small difference due to terminations could make the one cable 0.025 and the other 0.015. Now you can see that the resistance differential is potentially a problem. If you use smaller cable (say 6mm2, which would still be legal) then the nominal resistance would be about 0.1Ohm, now a small change in due to terminations would only change that from 0.105 and 0.095. So now a small resistance change is not a problem. On my two inverters I have noticed that despite my best effort at getting the cable lengths exactly the same, and terminating exactly the same way, the one inverter always runs with more load. There may be other reasons for this that I am unaware of. Indeed it is.

Having read through this with some interest I would say that your best bet may actually be Victron Quattro units 6x10kW. Coupled with each would be 250/100 MPPTs and each with about 40kWh of storage. The reason for going even larger than the 8kW would be the fact that air-conditioners are particularly unpleasant loads at start-up. Additionally the Quattro gives you the option of connecting generating power as a secondary AC input and they have the option of running PV on both the AC and DC side which allows you to connect some of the panels (via a Fronius) on the AC side thus sparing you the need to couple all PV on the DC side. The Victron website has a few reference projects using Quattro units at roughly this scale. Disclaimer: I do not work for Victron and don't run them in my setup.

I'm not sure if it is of any benefit here: For a few years I ran two PF0.8 5kVA inverters in parallel until a lightning strike right outside toasted their communications boards. They were replaced by new Mecer units that are PF1.0 5kVA. I can confirm that the newer units are significantly louder than the older units. As Coulomb puts it, objectionably loud. I can also confirm they are always loud even though the temperature is never high and solar production is always well within the nameplate capability of the units. The WAF on these units dropped from 10 to 1 as a result of the noise.

Interesting topic. I have something similar. Two parallel inverters. Breaker on the supply side of each and breaker on the output side of each. Breakers on the supply side are 40A each and on the output side are 50A each. Single pole (common neutral) on the supply and double pole on the output. I currently have one isolated and removed (long story) and the other is operating seemingly well. I tried to match wire lengths on the input and on the output. My mistake: I think I oversized the wires on the output because I had a future upgrade in mind. My wire size is 16mm2. I'm fairly convinced that even though I attempted to match the wires as best as I could I think with wires that size small differences can make a big difference. Opinions? I can say that in most other respects the system seems to work well and has worked well for quite a long time (barring a lightning strike).

Hi, thanks for the quick response, sent you a WA.

Hi, are all the units still available?

Ouch. OK, that is on the other side of the country. Let me see what other options I have. Does it have a parallel comms kit?

Where are you based?