meetyg

Well, my Anenji had been working great for the past few months, ever since I got it. I am amazed at how quiet it is, compared to many other all-in-one inverters I've tested. It also works great with 2NO/2NC contactor for N-G bonding when grid is out. (one NC port is not used of course). It's charging algorithm for Lifepo4 isn't perfect, but works alot better than others. It also tends to over-report it's solar production by around 10% (reports around 100w more than actual, when supplied with almost 1000w of PV). But other than that I'm pretty happy with it. I think my quest for searching of the best 24v all-in-one cheap (Chinese? ) inverter is finally over!

The Anenji 4000w 24v is also a nice unit, if @ericson is looking for 24v specifically. It's also one of the quieter all-in-one inverters I've tested. No need to change the fans on this one, and it support higher PV voltage than the Vevor 3500 (although externally they look similar). Do note that it supports only around 3500-3800w maximum from battery alone. If you add PV, then it can support the full 4000w.

From my experience with various inverters that have SOL mode, you need to pay attention to the wording in the manual: Your manual states that when solar is available, it will be used along with battery to power the loads (if battery voltage is above the setpoint), like SBU. But after sunset, or when when solar is not available, loads will be powered solely by the utility/grid (like UTI mode). Other inverters may use the SOL term similar to SUB (SOLAR-UTILITY-BATTERY) mode. In this case, the wording will state something like "Solar and utility will power the loads at the same time".

I have a 25A version and it is fairly silent. Also not running very hot. Around 42 degrees Celsius with thermal camera, after running for a few weeks. I don't think that these take alot of current after initial power to the coil. Some of the better quality ones have an optimized circuit to reduce the current and heat to the coil after initial start up. One advantage to using a 2NC and 2NO in the same unit, is that even if the coil fails, and the relay closes, you will not trip the input RCD because input AC will be disconnected. I bought a few spare item of these relays, in case I get a failure. I like your idea of indicators!

Thanks for your reply. It sounds weird that they didn't include that AC board. I will have to check mine. Anyways, I am using these cheap contactors from Aliexpress: https://www.aliexpress.com/item/1005001339814821.html So far no issues, running 24/7. An industrial one should probably be even better.

BTW: I would like to hear your opinions on this Anenji, I have one on order, waiting for it to arrive.

This is exactly what I have done with some other inverters: It works well and is the best solution in my opinion. It disconnects AC Input to inverter so no chance of some kind of backfeed, and allows RCD to be used at output of inverter. Just remember that the N-G bond on the output needs to be before the output RCD (if you choose to install one on the output).

Just for reference, I have solved this issue. The solution is tested on two different installations and is working well. The solution is to disconnect grid input to the inverter, while N-G bonding the output of the inverter. This is made possible by one relay that has 2 NC ports and 2 NO ports. Although only 3 terminals are used, I could find one that exists with 2 NO and 1 NC ports. You connect grid input (L and N) to the NO ports, and the N and G output to the NC ports. Of course you connect grid supply to the power of the relay. When grid is up, the relay holds the input to inverter, so inverter has grid input, but N-G of output is open (not connected). When grid goes down, the input to inverter is opened (disconnected) and N-G bond is connected.

What are you "back to battery" and "back to grid" voltages?

Wow, 8 years, that's impressive! Thank you all for for the helpful information. My MUST inverter has been running reliably for the past two years approximately. But I know it's full of dust (has no filters). While it's placed indoors, it has a tendency to collect alot of dust. I recently took it down, but haven't opened it yet. I looking for a worthy replacement that has filters and SUB mode working properly (preferably with low PV voltage ~ 150v max). But have yet to find one (3kw / 24v). I am currently testing a Powmr unit with dust filters and SUB mode (150v PV MPPT max), but SUB mode isn't working as expected, but that's for a different post. I was asking because I'm somewhat liking these POWMR units, but am afraid that they will fail prematurely. So your comments are very helpful.

Yeah, of course Axpert/Voltronic are better known and can be repaired. But I'm asking what we can do to prevent the need for repair in the first place.

I would like to know from your experience: What kills inverters (mainly all-in-ones) the most, and what can we to do to prolong thier lifespan? I am mainly asking this, as more and more cheap units are available (Voltronic clones and the like) in the market. I mean if we all could afford the high-end stuff (Victron, Schneider, or even genuine Voltronic, etc...) I guess we wouldn't be asking this... Now I know that you get what you pay for and sometimes buying cheap will cost you more in the long-run. But again the up-front costs for these high quality units is sometimes out of reach. Sometimes we want to start small (cheap) and simple and upgrade in the future. I assume the main problem with some cheaper units is simply low quality components (capacitors, FETS and IGBTs). Or maybe components that don't give much headroom or aren't sufficient for the specs of the inverter. But how can we get around this and still enjoy our units for years to come? So any tips would be appreciated... Thanks.

https://solar-assistant.io/ It runs on a Raspberry Pi. It costs a one-time fee for the license, but if you register on thier site, you can run a free trial for about a month.

Sounds like this are calibration parameters, which I wouldn't touch unless you know for sure what you are doing. Other parameters you can change as you like. Personally I use Solar Assistant connected to my MUST PH18-PLUS, which makes remote monitoring and settings changes much easier.

Circuit breakers have a trip curve for short circuit protection. This means that in order for them to open when a short circuit occurs, they need 3-5 times thier rated amperage to flow. This depends on the curve type. I think they most common curve type would be C, because B type, which is more sensitive, can cause nuisance tripping when power on large inductive loads (such as motors, compressors, etc...) because of the high initial inrush current needed to start up these loads. Most HF inverters can sustain a load surge of 200% of thier continuous capacity, but only for a few seconds. So it seems logical that the inverter tripped first, unless you have B curve breakers.