BUG: Peak Shaving is limiting my output power through AC-IN which causes it to not trim as configured. It only happens with external input

To explain what is happening I have to say that I have a Spanish tariff. Which has two powers, peak power (the meter has this power from 08:00 to 23:59) and off-peak power (the meter has this power from 00:00 to 7:59, weekends and national holidays with fixed date).

My house until recently had 3.3kW in both powers. But to reduce costs I have changed and I have put 1kW in peak and 3.3 in valley. How do I manage this with Victron? With NodeRED.

After a week now, I have seen that the Power Control Switch of the meter has tripped several times. Then I started to check if the Peak-Shaving function was really working correctly. It was indeed working correctly.

So what was wrong? The inverter was not contributing as much as before to the loads (the non-critical ones). Then I started to look (my non-critical loads are connected directly to the grid and not to the specific Victron port) and bingo, I found what is giving me problems. The Peak-Shaving function is limiting the input current through the AC-IN of the Multiplus. So as I have configured not to import more than 5A in the PeakShaving, the peak shaving is telling the Multiplus not to let more than 5A through the AC-IN. And when I am consuming much more the inverter is exporting -5A.

Please I need someone from Victron to fix this in VenusOS so that it works correctly when the loads are not hanging from the inverter and there is a meter available.

Victron Team: I have the remote support activated if you want to take a look.

@mpvader

Please show your setting from the VE-Configure:
‘Input current limitation’ … Shore Limit

I have 40A but I have the box that can be overwritten.

Then limit it to ‘1kw’ here … I don’t know your mains voltage …

I don’t think you understand me. This is what is happening to me.

A temporary solution I can try is to remove the overwrite input amperage tab in Multiplus but this would only be a small workaround (in case it works). And not the solution.

Ah ok … I thought it is only allowed to charge your Battery with 1kw …
You may not draw more than 1kw in total from the grid :+1:

I also see a problem with Peak Shaving, as it is set by amperage, it has the disadvantage that the mains is not at 230V all the time. It would be better to set the power and have the Cerbo GX calculate the amperage at which it has to limit.

Exactly

But you could use the ESS Function and “play a little bit with the Main Setpoint” via Nodered

The workaround that I thought was going to work, doesn’t work. Cerbo GX does not respect the setting that the input amperage cannot be overwritten and overwrites it anyway!

I think I understand your problem but I also think that is not necessarily a Victron bug. The input setting for the multi’s allow you the limit the input. That decision is yours to make and can be due to an actual grid limitation, cabling, breaker limits, whatever.

You can try two things:
Set the input limit to a larger number. The number your Multi can peakshave (20A ?). But set the Settings > ESS > Peakshaving config to your grid (5A) for both import and export.

Or simply connect all loads to AC-OUT. But fairly sure that’s not what you are looking for :slight_smile:

The first option should accomplish what you need. Keep the grid at 5A for both import and export and peakshave another 20A to AC-IN (or OUT) if needed.

I forgot. If this is what you’re looking for and your capacity changes during the day.
I should be these settings in node red: com.victronenergy.settings/Settings/CGWacs/AcExportLimit / AcInputLimit

My input cable on the MP II can withstand up to 40A. But I can’t configure it, it is overwritten by the Cerbo GX.

I’ve moved my (non-critical) loads to AC-OUT 2 temporarily, let’s see if the Victron team can do something.

The first option should accomplish what you need. Keep the grid at 5A for both import and export and peakshave another 20A to AC-IN (or OUT) if needed.

This is what Cerbo GX won’t let me do.

I forgot. If this is what you’re looking for and your capacity changes during the day.
I should be these settings in node red: com.victronenergy.settings/Settings/CGWacs/AcExportLimit / AcInputLimit

I am already doing this.




Not sure I fully understand what I’m looking at as there is a mix of screenshots where the Multi grid current limit is configured at 6 and at 40. Both are greyed out. Whereas in your original post the setting is blue, available for customisation.

I only use ESS/DESS so I am not that familiar with the abilities of the system without a configured ESS assistant in the Multi’s. From the little I know:

  • you can configure the input limit in VE configure, serving only as a backup ?
  • you can configure it in the device > multi settings on the Cerbo (the number in A represents the input limit for single unit in case of a 3-phase system)

Don’t think you can configure it in the ESS assistant. Not sure. In VE configure there is also a setting related to handle unstable grid. Could that be related to your problem ? Can you find out what settings you have configured ?

Other tools that may help you figure out your config include dbus-spy from the prompt. And by replacing /dashboard with /diagnostics in the VRM gui.

It does not appear in blue because I have set in the VE Configure that it cannot be overwritten. The problem is that it is limiting the input and output of the multi input.

It should not be varying the amperage of the multi input when I have an external meter.

By limiting the amperage that comes out of the input it is causing me to have to take more power than I can take from the grid

You mean the overruled by remote setting ? I have that enabled in my setup so I can use the Cerbo to change it (taken from txt export of VE Configure):
TAB: General
System frequency 50Hz
Shore current 25.0 A
Overruled by remote checked
Dynamic current limiter unchecked

And the settings in the Cerbo is also 25A so in my case it wouldn’t matter. Could it be that you have accidentally checked Dynamic current limiter ?

If your grid capacity is variable over the day than the overruled by remote setting in VE Configure must the checked for you to use NodeRed. But you probably only did this for testing ?

Other than that it has to be something specific to your setup. I have used these settings from the start and other than some known bugs I can still easily change around the values and immediately see the system working as designed using the new numbers.