question

andy156 avatar image
andy156 asked

Does the data I get from the VRM api exist on the cerbo?

I am downloading the data from https://vrm-api-docs.victronenergy.com/#/operations/installations/idSite/data-download to make a summary display which is similar to the sunny portal.sma-sunny-portal-info-dati.jpg

All the info is available in 15 minute chunks from this api.

However, the 1215 data does seem to arrive for 10 minutes or so. Are the same datapoints on the filesystem of the Cerbo GX? Or is it a case that the calculations to create them are done in the cloud? If I can get better resolution than 15 minutes that would be useful.

cerbo gxVRMapi
sma-sunny-portal-info-dati.jpg (47.2 KiB)
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Alexandra avatar image Alexandra ♦ commented ·
@Andy156

Have you set the cerbo to log every minute to the VRM?

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wkirby answered ·

System power is available directly from the Cerbo, use MQTT or ModbusTCP to extract that data.
Energy is calculated in the cloud.
If you want, you can calculate energy yourself using the power and then integrate using a left Riemann sum.

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andy156 avatar image andy156 commented ·
Thanks, I was trying to avoid that but hadn't found any Energy data. I shall get to it :P. What's a more accurate way of doing it regarding the power data and timings? I've been using the node red nodes that seem to fire about every 5 seconds, so that or the MQTT?
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wkirby avatar image wkirby ♦♦ andy156 commented ·

Is that the W to kWh node? I have not used it before, but I presume it's pretty good.
I have Home assistant doing left Riemann sum integration for me and it's pretty accurate with a sample rate of 10 seconds.

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andy156 avatar image andy156 wkirby ♦♦ commented ·

The various nodes from here https://flows.nodered.org/node/@victronenergy/node-red-contrib-victron. Used in something like below

screenshot-2023-02-08-at-091348.png

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screenshot-2023-02-08-at-091348.png (580.0 KiB)
cesar avatar image cesar commented ·

Hi,

How do you handle to get the time from ModbusTCP reply?

thanks,


César

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