Yeah it looks like its temperature derating.

Just as a note, it is normal for the blue line to be higher/lower than the red line. The blue line expresses a wish. The GX device doesn't know what the capability of the Multi is, so it simply tells the Multi what it would like, and the Multi does the best it can. In this picture, the blue line indicates what would be required to get the grid consumption to zero (in other words, you have 3kw worth of loads at that time), and the Multi does the best it can (2400W... until it hits the green circle).

Derating is normal, but as I said, I've never seen a Multi do that unless it has ventilation problems or it lives in a really hot country.

Edited November 13, 20196 yr by plonkster

@plonkster Thank you kindly!

On 2019/10/14 at 4:44 PM, phil.g00 said:

Worth a shot, check your DC connections in the inverter for tightness. A loose connection will build up a lot of heat when the current goes up.

I should probably check this? I used large lugs and remember thinking when tightening the nuts that the surface contact area between the lugs and inverter pins wasn't that great....

Edited November 13, 20196 yr by deapsquatter

14 minutes ago, plonkster said:

Yeah it looks like its temperature derating.

Is this proprietary software to see this, or is it deep VRM?

Just now, phil.g00 said:

Is this proprietary software to see this, or is it deep VRM?

On VRM, on the advanced tab, top right, you can download the data in xls or csv format. Some data is considered "debug" data and might not be available to customers though, but you can usually get a pretty good idea of what's going on. I used that data to draw the picture, using a normal spreadsheet product 🙂

@plonkster, Thanks I knew about that, but I think what the GX is commanding the Multi to do is in the debug mode.

43 minutes ago, deapsquatter said:

@plonkster Thank you kindly!

I should probably check this? I used large lugs and remember thinking when tightening the nuts that the surface contact area between the lugs and inverter pins wasn't that great....

Just checked - torque is good. No longer think that this is the issue. @plonkster shall I put in an official support request?

1 hour ago, deapsquatter said:

put in an official support request?

Yes, do that.

@plonkster at the risk of sounding like a stuck record...  if this 3000VA Multiplus II also has the issue with that bolt - I would really like to know if mine has that issue as well.  I would be a bit unhappy if my inverter is also suffering from this issue, but I only find it out once I have to start using it hard.  Why can the known list of serial numbers not be published somewhere?

1 minute ago, admiral said:

also has the issue with that bolt

Only one batch of 5KVAs is affected. If there is an issue here it is a different issue.

5 hours ago, plonkster said:

 

@plonkster - To me it looks like the Multi is delivering 2100W Before derating at the green circle - not 2400W?

40 minutes ago, Ironman said:

 - To me it looks like the Multi is delivering 2100W Before derating at the green circle - not 2400W?

There is 300W on the output that is not taken into account here. So 2100W pushed out via the input plus the 300W on the output and all the horses are in the stable 🙂

 

@plonkster Thanks for the help yesterday. Some feedback. Ran exactly the same test this morning. 2000W load started about 8:53 and derating started about 9:50.

Ac/ActiveIn/L1/P = -1552

Hub4/L1/AcPowerSetpoint = -1936

What are the various things that will cause Hub4/L1/AcPowerSetpoint to decrease to below what the Inverter is capable of? I have noticed that as my Critical Loads increase that value will decrease. What are the things that will cause it to decrease while Critical Loads stays constant?

Edited November 14, 20196 yr by deapsquatter

1 hour ago, deapsquatter said:

What are the various things that will cause Hub4/L1/AcPowerSetpoint to decrease

Right, teaching hat on. On the GX device there is a piece of software called hub4control. It's not open source. The AC setpoint mentioned above is adjusted by hub4 control. So your question comes down to what hub4control looks at.

Hub4control wants to adjust the power level so that the measured AC input (measured either by a Carlo Gavazzi meter, or the Multi itself) is zero. So hub4control works out how much power it needs to command of the Multi to get that done. It does not know the size of the Multi, so if you use a lot of power, it will command all of it and the Multi will do what it can.

But, it also looks at the managed battery's (aka one with a canbus cable) discharge current limits, and from that it works out a number. But it gets more complex, because the AcPowerSetpoint controls how much power is fed from the INPUT of the Multi, so where you have a managed battery with its own limit, you need to first subtract the power used by loads on the output, and what remains is then the max that may be fed into the input (if you don't do this, you may exceed the current limit imposed by the battery). For this reason, you will sometimes see the setpoint go down when loads on the output go up, because it is trying to remain within the limits of the battery.

Other than a limit from your battery, there is also the Maximum Inverter Power setting on the ESS menu.

Great explanation - thank you!