Megarevo RxLNA Discussion

flygeek said:

Alright, some progress. I decided to navigate through the menu tree and see what I could flip to try and clear the "08: Grid Low Freq" error. There is a setting: Setup > Grid Setup and you can change the locale for the the grid. I flipped it from US_CA to CUSTOM and I heard a click and the EPS and Alert lights went out. I then flipped it back to US_CA and the lights stayed off.

Going to watch the data over the next day or so and see if all behaves.

Click to expand...

You, know Flygeek something similar happened to me but with the PV not charging. PV would not begin charging my LiFePO4, unit was in Lead acid mode since, at the time there was no Canbus on my BMS.. Finally i switch from lead acid to Lithium waited a few seconds and switch back to lead acid and all of a sudden it started charging with PV. Been working fine ever since. I guest the software is bugging and has difficulties releasing the last command.

Ok, Reecies15 it's 6am i turned off the isolation test last night and since the grid went down at my home I turned off the grid breaker, so when the grid returned i will still be in EPS off grid mode. So far no shutdown, and PV is charging. Looks like this maybe a winner! Will monitor for a few days.

I restarted the inverter last night (first time since settings change) and I didn't get watchdog or "signal restored" alerts from Blue Iris for my shop mounted cameras this morning. I'm not saying they didn't turn off, but I'll have to pay more attention tonight to see if the test runs.

NCSolarGarage said:

I restarted the inverter last night (first time since settings change) and I didn't get watchdog or "signal restored" alerts from Blue Iris for my shop mounted cameras this morning. I'm not saying they didn't turn off, but I'll have to pay more attention tonight to see if the test runs.

Click to expand...

I am on my second day off grid with PV isolation test disabled, so far so good. No resetting of DVR, cameras, internet, clocks and out of wack smarthome connected device.

jsmetalcraft said:

So beings your a bit more educated in these and electronics, what is your opinion on the processing part of this inverter? More then Up to the task, will do the task, or it has to work hard to keep up? Just seems at times it struggles with tasks. Maybe the way the software is written.

Sounds like you need a job at Megarevo or do like China does and reverse engineer and write your own. LOL

Click to expand...

I'm slowly figuring out that the user interface part of the Megarevo is a pretty standard STM32 controller that you'll find in a lot of embedded devices, which jives with wanting to keep manufacturing costs low and standard. It definitely has enough processing power to drive the unit. Think of it like an Arduino device.

It does emit info and error messages on a console, but I haven't checking into how to read those - the 'stream' firmware updater might have the capability (with the ARM and DSP buttons - they launch a different, but blank screen).

jsmetalcraft said:

No, I mean that the BMS and inverter say that they each support both communication protocols. I don't know if either work. Guess we will find out someday.

Click to expand...

seplos BMS doen't support both CAN & RS485 only one of them depending of which version you order. don't try to upload RS485 firmware on a CAN version (or the other way) you going to brick the BMS.

flygeek said:

I'm slowly figuring out that the user interface part of the Megarevo is a pretty standard STM32 controller that you'll find in a lot of embedded devices, which jives with wanting to keep manufacturing costs low and standard. It definitely has enough processing power to drive the unit. Think of it like an Arduino device.

It does emit info and error messages on a console, but I haven't checking into how to read those - the 'stream' firmware updater might have the capability (with the ARM and DSP buttons - they launch a different, but blank screen).

Click to expand...

So the (in my case) USB C port is the serial port hookup ? Just a USB <-> USB cable, config the serial port on your OS and you should be able (famous last words) be able to read (some) console messages?

Well it ran very well off grid for 5 fully days with the PV isolation test disabled. I now turned on the Grid and will run for a few days on grid with the PV isolation test disabled. Just to make sure nothing weird happens. When i turned on the grid breaker the switch over was perfect like the Deye or sol-ark. ?

Another member asked about the boot sequence earlier. I was doing some testing today as I get Bus over vol and Bat over vol warnings. Things been running smooth for the last day. Earlier some posted that they run on lead acid setting. When I tried I had issues, so went back to lithium. I have Sepros BMS communicating via can bus to the inverter.

I made a change in lead acid to see if it, or the inverter was using or looking at both settings. Lithium has no settings. When I entered out of setting things went hay wire even though I changed back to Lithium. Setting made no difference. But as I measured the battery bus on the inverter it was like it was searching for the battery voltage. Problem was it would go from 59v to the actual battery voltage slow and then jump up to 59v again. On and on. I would get a bat over vol error and the BMS would show a warning.

Anyway I had to end up rebooting. Only way I have found so far, and the reboot sequence I follow is: Battery first. Wait for EPS mode and discharge on the battery. Then turn on PV until you see drawing watts from PV. Then turn on Grid. Your Mileage May Vary, or is there a boot sequence that others have found that work for them?

MNRosado said:

Well it ran very well off grid for 5 fully days with the PV isolation test disabled. I now turned on the Grid and will run for a few days on grid with the PV isolation test disabled. Just to make sure nothing weird happens. When i turned on the grid breaker the switch over was perfect like the Deye or sol-ark. ?

Click to expand...

Did 4 days on grid with PV isolation test disabled, and again ran very well. I think i now have a use-able inverter

any recommendations which firmware is the stable one to use?

minerva said:

any recommendations which firmware is the stable one to use?

Click to expand...

I'm kind of surprised you unpackaged it, I would've been tempted to put the new inverter up FS after your previous experience!

minerva said:

any recommendations which firmware is the stable one to use?

Click to expand...

I've updated to the latest (1.03.11 and 1.04.09) and apart from the initial glitch requiring a change in power locale - all has been good. It's been feeding data to the solarman console (pro.solarmanpv.com) reliably for about ten days.

One thing I did notice, however, is when I added a second string to the unit (I'm in an urban, flat roof environment) the unit rebooted after about a minute, but then recovered nicely.

My config is a 120Ah LifePO4 battery, grid-tied, Load1 fed into a transfer panel and Load2 on an isolated panel and 11x 340W Hanwha Q-Cell Duo panels across two strings (6 and 5). I'm on the grid, but don't feed back into it (Anti-Reverse is enabled).

Wet1 said:

I'm kind of surprised you unpackaged it, I would've been tempted to put the new inverter up FS after your previous experience!

Click to expand...

I have 3 fire extinguishers standby and wear glasses!

jsmetalcraft said:

Mine shut down right at dawn as before for the 5 minutes. I also have not had the data stream shut down, yet. knock on wood. That and maybe a bit better synce with the grid are the only things I have noticed improved.

The battery issue seemed to resolve after about 20 minutes.

Click to expand...

I happened to be in the basement around 5:30am this morning and I noticed that the unit rebooted about six times in a row for the testing. The power didn't go out to any of the panels (or if it did, it was very quick).

flygeek said:

I happened to be in the basement around 5:30am this morning and I noticed that the unit rebooted about six times in a row for the testing. The power didn't go out to any of the panels (or if it did, it was very quick).

Click to expand...

I now have 2 of the 4 mppt strings hooked up , each with a DC disconnect.
When I disconnect a string, nothing happens except loss of power of the string.
When I re-connect it however, it always needs to start over, not a cold start but a new find of the max power.
From what I understand, each mppt is converted to some "DC middle bus" and from there the AC is generated.
If that bus has a sudden increase of available power, it seems to need to "think about it".
Could it be that at 5:30am it was just enabling a new string ?
I am always amazed by the startup graphs.:

There is a high voltage very early but it only starts producing amps when there is enough solar.
I live in a valley and both at the beginning and at the end of the day I have a lot of shading going on.

Here is the shot of mine. What I see is in the morning when the array voltage reaches 80+ volts it goes into the test. Looks like I get a voltage spike of 150-180 volts on the test. Then back to 85 volts. I do have the isolation test turned on.

@jsmetalcraft - now that you mention a morning spike, I see the same in mine, right around 5:30 when the voltage starts to pick up. @fromport - I noticed the same thing when adding a string - a soft reboot. I have a 4:2 PV combiner box outside and can flip the strings off and on if necessary.

I also need to get a bigger battery (my 280 Ah is at the cottage), you can see the unit cutting out the PV feed when the battery is full. Since I don't currently feed to the grid, the extra power has nowhere to go.

Good morning, I am testing the inverter off-grid with one string solar panels and one lithium battery connected via CAN. For some reason, the inverter only charges using the solar panels for around 30 minutes and then stops giving error "bus over vol". If I do full restart of the inverter, it charges again for around 30 minutes before stopping again. I have firmware version ARM V1.03.11 and DSP V1.04.09. Anyone an idea what could be causing this?

Manyaka said:

Good morning, I am testing the inverter off-grid with one string solar panels and one lithium battery connected via CAN. For some reason, the inverter only charges using the solar panels for around 30 minutes and then stops giving error "bus over vol". If I do full restart of the inverter, it charges again for around 30 minutes before stopping again. I have firmware version ARM V1.03.11 and DSP V1.04.09. Anyone an idea what could be causing this?

Click to expand...

How many watts total is the array?
In 1. Setup>2. Grid STD>1. React Mode>What is your setting?
How many amps are you charging with?

Reason I ask is I have reported the issue with Bus over VOL and Bat over Vol. Been testing and I used Power Factor instead of React Power yesterday. Ran one day smooth as butter. Knock on wood.

As far as charging I had seen similar but only spikes where the charge would quit but picked right back up without any Warnings. I am about 400 watts over paneled on each three arrays. I covered a few cells on each array and seem to help. I also found that with V1.04.09 I can only get about 70 amps before I have drop outs. Before the update I had gone as high as 140 amps without issue. Ran 100-125 for months, again without issues.

Curious to see if we can narrow down some of these issues and understand some of the setting more fully.