Hi Victron,
I really like DESS idea. From begining all was working fine, but some changes around September/October last year were introduced and DESS started working weird.
DESS on
Green Mode
charging my car - but instead of taking of PV it is using energy from GRID (why ???) same behaviour I have seen several times. But it was working fine last summer. Can someone advice me what I am doing wrongly or what is happening ?
VRM - PV makes 9kWh but EVCS is charging from GRID
I think I have everything done correctly.
Please let me know if you need anything else from my side. (my vrm ID, access, etc…) I really would like to use DESS but this bug needs to be solved.
I do not have close answers, but I saw that your battery charge limits are wrong in the DESS config. You said it would be capped at 4,8kW but you see more than 9kW in the screenshots.
DESS is pretty picky if the values do not match the real world and not just some wannabe or theoretical values. If you really want the batteris to be limited to 4,8kW, you should set this limit in the DVCC config.
I have updated my settings. (DVCC is set to max charge 200A - which translates to 9.6 kWh charge / discharge).
I have updated my settings.
For example today there was issue with DESS (green mode) that it would be selling all solar to grid instead charging battery - based on VRM prediction battery was supposed to be charged to 40% max and then in the evening discharged. Why is it that ? I would expect that battery would be charged first (GREEN MODE) and any surplus would be sent to grid.
Am I missing something ?
2nd question: " Yes, enable charge battery from grid restrictions" - does it mean that battery is NOT charged from Grid ? They have changed the text several month back and now I am confused what it actually means
From the screenshot, I assume that the schedule of DESS had a scheduled battery charge at that time.
And if that’s the case, it will charge the battery at it’s precalculated rate, no matter if you turn on an ev charger or not.
Only if the charge is “opportunistic” (we call that self consume mode), it will priorize loads and reduce the battery charge rate to avoid grid pull.
no - it was not scheduled. (I will explain myself in more details just in case if we are talking about different things).
By Scheduled battery charge - I understand that DESS every 14 days charge battery to 100% neverthless from solar or from grid. Basically it will balance out battery once every 14 days.
I don’t know exact dates when it happens but I know that it is doing this when in main page in VRM under DESS section it says “today is planned balancing” or something similar. And it was not there.
So I assume something else was happening.
Guys, I have question - would it help if I could install NodeRed and somehow import it from VRM? Or is there anyother way to know what DESS is doing and planning ? Some logs ?
Right now it is black box which doesn’t work everytime same and I need to have overwatch. But it was working perfectly fine let’s say Spetember last year.
No, the “scheduled charging” i’m refering to is actually invisible currently. The local system has many ways of follow the DESS-Roadmap, and one of them is ensuring a certain battery charge during an hour, taking energy from grid if required.
And if that is the schedule, while you plug in your EV, Battery will continue to charge and not cover the EV consumption.
Obviously, this kind of schedule most likely happens during times of cheap energy - and this is also the most likely time for pluging in your EV, which then makes your system charge the home battery plus the EV from grid.
If you could give me your VRM-Installation id (the numeric one in the URL to access vrm portal), I could lookup if that was the case. But from the “jump” visible in the VRM predicted Soc-Plan and the current grid prices, i’m 95% sure this is, what happened.
However, there is no predicted “grid2battery” for that hour, which kinda means: VRM requested to charge with 9200 Watts now, because due to the predicted solar and consumption it was certain to achieve that charge-rate through solar only. (But in that case, the solar was kinda “reserved” for the battery, and any additional consumption then would need to come from grid)
On better days and higher SoC levels, VRM will schedule with a more opportunistic charge-strategy, saying “Cover all loads first, and send the remaining energy to the battery only”. During these kind of roadmaps, plugging in your EV would lead to a lower charge rate as you expect.
thank you very much for your response.
my VRM id is: 370939
Today , current situation:
it is raining outside, but it makes almost 1kW
instead of charging battery it is sending surplus to grid (I am on GREEN mode - it should charge battery first, right ? )
when you check the curve of battery charging - it seems like it will not charge it today at all - why ?
I don’t want to sell my surplus I would rather charge battery and have as full as possible for later today so I don’t have use grid to keep my house running.
I am attaching screenshots from VRM + my DESS settings (can you check if it is done correctly ? )
I buy for FIXED price for electricity
I sell for SPOT price
battery pylontech 4x 4.8kWh (I think they called them pylontech US5000)
when you will be inside of my system. I had problem with Cerbo and gui-v2 - screen got frozen every time.
I have find out that when I switch to classic view everything works.
Some people suggest that CPU is too slow for that new GUI.
Can you check the CERBO as well ? How are the parameters, CPU, RAM ?
