MPPTs are being switched "OFF" and "ON" every few seconds - WHY?

Agree with the 8000VA / 6400W :slight_smile:

Set to

This is Africa and I can not change the temperatures :slight_smile:

Switched OFF

Indeed, but it is important to be aware that this is a factor in how the system will perform and behave. The BMS can send requests to limit or stop charging due to temps, which is why I need to see those limits charts from VRM.
If the BMS is stopping/limiting the chargers and you have decided to bypass that protection, you could be causing problems for yourself down the line, something the manufacturer may not be happy with.

What is your battery config? I see it is BYD but only listed as 100AH which is not ideal for a larger inverter and the amount of MPPT power you have.

The system is operating in the same location and with the same devices since FEB/2019.
I was off grid for the first 5 years, and survived on this battery :slight_smile:
Solar power at daytime is usually more than sufficient to cover all my loads.

3,605 sunshine hours per year and sky is clear or partly cloudy 92% of the time

I added a few fans for better ventilation of the inverter about a year ago.
Does help a bit at higher environment temps.

I know, the battery is bit on the small side and can only discharge at 70A!
But this was an the only choice I could effort back in in 2019
If I remember correctly BYD 48V(was about ~USD3000 in 2019)
I am VERY happy with the BYD battery

After more than 7 years in operation, SoH 99% :slight_smile:

I only connected to the grid about 2 years ago (got one of these suppliers grid meters import/export meters)
Makes it a lot easier, not to watch power consumption, especially when running from batteries :slight_smile:

This was just after sunrise!

You need to download the BMS limits chart that covers a period when this issue is happening.
It is under VRM advanced widgets.
If chargers are powering down under BMS control, it is most likely that the BMS is sending limits for some reason, or, you have a defect that has developed somewhere in your wiring that is causing voltage discrepancies. This isn’t uncommon in older systems and warmer temps, we inspect systems here annually, you’d be surprised what can come loose or just wear out over time.
Voltages need to be checked manually with a reliable meter.

DID that :slight_smile:

I will go (again) through all connections tomorrow morning.
( I usually check every year, and I found loose connections only after the 1st year of operation.)

I will do some measurements :slight_smile:

…thanks for helping :slight_smile:

The missing link is that BMS limits chart. I showed you how to select it above.

I will setup as suggested and report when I have some visible results

lets see

VRM has stored the data historically, so you can rewind to times when this has happened and pull past charts.

I know, but I will also setup a Grafana graph.
Because logging is done from the MQTT Broker and therefore, every change is recorded :slight_smile:
like this graph from above, showing 5 Minutes of

Here is the current graph from VRM - last 3 hours

Last night I went through most of the cable connections.
I found nothing, that was loose, to cause any problems.

I then disabled the BMS > then disabled DVCC and then restarted the Quattro VE.BUS

After that enable the BMS and DVCC again.

This morning started promising, but then it starts again @ about 10h15 :frowning:
This are graphs for the last 6 hours
I disabled the BMS controll of the MPPTS @11h38

As before, I do NOT identify anything, that might cause this behaviour :frowning:
Tomorrow morning, I will go through a few other connectors!

We need to see the matching CCL chart that overlaps with the grafana charts.
The VRM chart shows the battery restricting charge a fair amount. CCL is 70A, and the panels when running, are pretty much supplying that, which is a high rate of charge.
We also need to see for that window, what the difference between max and min cell voltages are.

This is what I can select in VRM:

..or where would I find: max and min cell voltages?
I can only see the alarms, but all show “OK”

Here is the VRM chart for the last 6 Hours

Ah, ok. That won’t help. The battery isn’t sending that data.
Is there a firmware update for the pack? Some older batteries had these metrics added with newer updates.
Does yours work with the BYD app? If so, it is pretty easy to check and update them.

In any case it does not seem to be limiting on the first part of the graph that overlaps with your other charts.

I guess my BYD BMS is pretty old (2019) and I did a firmware upgrade back then.
Had to build a special cable foe that.

BYD APP? I don’t have that, let me check

Newer models have a gateway, typically an external box, that the beconnect app connects to.

This

Well I certainly have an older model :frowning:

I think I found something.
In Mqtt Explorer looking in the BatteryOperatingLimits I found this:

image

That is below float voltage. Shouldn’t that be what the BMS says?

The VRM graph shows a CVL of 56.5V :roll_eyes:

Where in the console can I change that?

Did you set it in DVCC?