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jeroenw avatar image
jeroenw asked

question about MK2/MK3 protocol for setting AcPowerSetPoint / ESS 'Grid Setpoint'

Hi, i am programming some simple functions on top of the MK3 USB interface. I have read the 'Interfacing with VE Bus MK2 protocol' pdf from the site and i have most of the thinks working. My goal is to implement the AcPowerSetPoint via the MK3 interface.

Does anyone know that the correct MK2/MK3 protocol variable is for setting and getting the AcPowerSetPoint? (aka Grid Setpoint)


When i look at 7.3.13.1 'RAM variables' from the MK2 protocol pdf, i see ID 's 14,15 and 16 and that could be what i am looking for. Unfortunately these ID's don't seem to give the right values.

(Does anyone know the difference between ID 14 and 15? The text is the exactly same for both ID's but they return a different value..)


Thanks

Jeroen


communication protocolMK3mk2
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2 Answers
danny-e avatar image
danny-e answered ·

https://www.victronenergy.com/live/ess:ess_mode_2_and_3

hi jeroen, in this link there is a ram variable that you can use. I'm working on the same thing at the moment. I managed to set the setpoint in the MK3 but it doesn't seem to send it to the Multiplus or anything like that. I can also read the setpoint variables and it matches what I set. I'll let you know when I get further

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jeroenw avatar image jeroenw commented ·

Hi Danny-e sounds great! I also found that sample and made some progress but got stuck again. Please see my other question "

Problem implementing the example 3.6.4 from the ESS mode document via MK2 protocol "

here on this forum.

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symbioquine avatar image
symbioquine answered ·

I also think the manual section 7.3.13.1 is wrong with regards to variables 14 & 15. Here's what I've been able to discover experimentally:

  • RAM[2] * RAM[3]: "vainv" (abs volt-amps passing through inverter hardware)
  • RAM[14]: "invpow" (abs watts passing through inverter hardware)
  • RAM[15]: "totpow" (Cumulative power used: load + charging)
  • RAM[16]: "outpow" (power to load)


1670950005645.png

The red area is where mains was connected and the Multiplus was charging my batteries.


1670950005645.png (151.1 KiB)
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