Hi Menno, thanks again!
Indeed batterycontrol is done via the inverter (modbus). Negative sign is charging, positive discharging.
I’m currently testing to see if Ultimate EMS would fit my needs/vision on EMS. But the first hurdle I’ll need to take is the battery, an AlphaESS. I can see the EMS sending ticks in the log but the battery does nothing. Is this a limitation on AlphaESS homey apps part?
Hi Jacco, thanks for testing!
Yes, I think this is a limitation of the AlphaESS app, not something the EMS can work around. The EMS decides “charge with about 4 kW” and logs it, but the battery device of the AlphaESS Modbus app only exposes readings: battery level, power, energy counters and status. There is nothing the EMS can write to, and that app has no action cards for the Modbus battery either. The API version of the same app only has charge/discharge time windows, not a power setpoint, so the EMS can’t steer it minute by minute. The “START” lines in the log are only the EMS’s intention.
There are two AlphaESS apps for Homey, and the official one from AlphaESS does expose the standard Homey battery control (a target power in W and a target power mode). That is exactly the interface an EMS needs. The EMS doesn’t write that yet for this type of battery, so I’d have to add it, and I can’t promise that it works with your Smile G3 T20 without testing.
Could you tell me:
- Which AlphaESS app your battery device comes from: the community app (Modbus or Open API) or the official AlphaESS app?
- If you install the official app, does your Smile G3 T20 show up there, and does the device have a “Set the target power” action in a Flow?
Until then the EMS can only read the battery. You can set the battery to autonomous in the EMS settings, so the log doesn’t show misleading START lines. The rest (solar, EV, heat pump) works independently of this.
I use the “community” AlphaESS app, is there any other? I see there is an official one but thats not modbus.
Yes there are 2 if I’m correct.
Neither really work.. I’ll try whipping something up with MQTT
Hi Menno,
I’m having troubles with EV charging via U-EMS.
It seems that the EMS is not reliable regulating chargecurrents for some reason. If I adjust chargecurrents manually via the Alfen Ace app it works fine. For example, forcing speedcharging via a flow, no change the charging currents, or 1/3 fases.
It’s also very difficult to find out in logs what the reason for a choice in EV charging is.
Can you have a look if I did something wrong, or that the EMS did’nt act as supposed? Thanks!
Hi Fred, thanks for the screenshot, your flow itself looks fine. I looked at your install’s log from Monday evening and found a few things.
1. Who controls the Alfen? The EMS has its own control for the Alfen ACE (Alfen.ProlineSingle app) and sets the current on the charger directly. Your flow sets the same current via the same device. If “Alfen ACE Lader - Buiten” is the charger selected in the EMS settings, both are active. The EMS also fires the trigger “EMS wants to set EV charge current” every time, so your flow only duplicates what it already does. You can try removing the current, start and stop flows and let the EMS do it alone. Could you check which device is selected as charger in the EMS settings?
2. Why 16 A / lowering didn’t work. “Fast charging” always uses the maximum current (16 A), limited only by the headroom on your phases, and the “fixed current” setting (9 A) only applies in the mode “Fixed”. That also explains the 8 A at the start (probably the phase headroom at that moment, I can’t fully confirm that) and why the 9 A had no effect afterwards. If you want a lower current, choose the mode “Fixed” with the current you want. I’ll make that clearer in the settings.
3. The connection problem (this one was on me). The Alfen ACE app doesn’t tell us whether a car is plugged in: there is no status, no connected flag, only the power. So the EMS assumed “car present” only when the charger was delivering power. Once the EMS had stopped the charge (or it paused for a moment), power was 0, the EMS thought nothing was connected and never sent a start again. That matches what you saw: no charging at first, and re-plugging not helping. Version 2.5.109 fixes this: the EMS now also uses the plug status of your EV (it reports whether the cable is connected) as confirmation that a car is present, keeps the car as “present” for 15 minutes after it last saw power, and tries a start every 15 minutes if nothing else tells it a car is there.
One more thing I noticed: several settings (load balancing, fixed current, start/stop delay) were changed around 21:15-21:50 on Monday, and each change reloads the EMS. That can make the behaviour look random. If it doesn’t start again, could you send the EV lines from the EMS log (Diagnostics)? Then I can see exactly what it did.
Hi Menno,
Thanks again.
The Alfen Ace is selected as charger. I’ll remove the current/start&stop flows. What to do with fase switching flows? Leave it in place, or does the EMS also handle this natively?
For the 16A lowering, i’ll do some testing today on this item.
As for the connection problem, beware: I already found earlier (before using the EMS) that the car app is not reliable on connections status. The Alfen Ace on the other hand is reliable, so maybe take in consideration to use that status flag?
Indeed I was trying (to understand what was happening) and debugging on monday evening, so I changed several settings during the evening. I’ll let you know as soon as the issue arises again.
Another question related to EV charging. I saw tour remarks in de change logs on use of home battery for EV charging. For me it’s not obvious to distilate from the plan when&why the choice for battery use is made. Is there anyway to make this more visual?
Hi Menno,
I’ve installed 2.5.109.
After that I connected the car to the charger with EMS on Solar&Grid and the Alfen started charging at 1fase, 6A = 1.3kW. Then I changed to fast charge (via flowcard “stel laadprofiel in”) and used the flow card “Laad EV1 nu naar 100%”, the EMS switched to 3 fases, and after that it took quiet a long time, before the command to charge with 3 fase 6A was given to the charger by the EMS. Why only the 6A and not full load 16A I don’t understand, load balancing in the EMS is switched off, this is done by the Alfen Ace, and there was plenty of surplus power present via the grid for that.
Any thoughts?
EV LOG’s:
[13-10 13:11:28] 
Extra laden gestart: doel 100%
[13-10 13:07:46] EV ADJUST | 6A×3ph≈4140W | min_soc_force(25%<=30%) | mode:fast_charge | €0.2680 rank:7/96 | SoC=25%
[13-10 13:07:46] EV fase 1F → 3F
[13-10 13:05:46] EV ADJUST | 7A×1ph≈1610W | min_soc_force(25%<=30%)+export(7A) | mode:fast_charge | €0.2680 rank:7/96 | SoC=25%
[13-10 13:05:43] Extra laden gestart: doel 100%
[13-10 12:52:46] EV ADJUST | 6A×1ph≈1380W | min_soc_force(25%<=30%) | mode:solar_and_grid | €0.2734 rank:11/96 | SoC=25%
[13-10 12:52:45] · Verbruiksplan tomorrow: nacht 5.5 kWh, 0 zonuren aangevuld
[13-10 12:45:46] EV ADJUST | 7A×1ph≈1610W | min_soc_force(25%<=30%)+export(7A) | mode:solar_and_grid | €0.2775 rank:14/96 | SoC=25%
[13-10 12:43:46] EV START | 6A×1ph≈1380W | min_soc_force(25%<=30%) | mode:solar_and_grid | €0.2775 rank:14/96 | SoC=25%
[13-10 12:31:45] Alfen ACE eigen solar mode uitgezet — EMS is nu de enige regelaar
[13-10 12:31:03] Alfen ACE eigen solar mode uitgezet — EMS is nu de enige regelaar
Thanks for the detailed log, that helps a lot. Two things explain what you saw:
- Only 6 A in fast charge: you have a minimum EV state of charge of 30% set and the car is at 25%. Right now that “minimum SoC” rule takes priority over every mode and forces the minimum current (6 A), so fast charge never gets to ask for 16 A. That’s a bug in the priority order: an explicit fast charge / “charge now to 100%” should win. I’m fixing this for the next version. Until then, temporarily setting the minimum EV SoC to 0 should give you full current.
- The long delay from 1 to 3 phases: the EMS waits for a few consecutive ticks before switching phases (meant to prevent flapping in solar modes). In non-solar modes that’s unnecessary, so I’m removing the delay there.
The fixed-current setting only applies in the “Fixed current” mode, not in fast charge. I’ll make that clearer in the settings.
About the car connection: I’m still looking at why the Mercedes “connected” signal doesn’t register immediately. Could you tell me what the Mercedes device shows for the connector capability while it’s plugged in?
The Mercedes Homey app is indecisive for connector status, independent of the (native) Mercedes Me app status (connected / not-connected).
Ultimate EMS 2.5.109
New
- PV forecast per roof: the forecast is now calculated per roof. Per phase you can tick “flat roof” (13° tilt, otherwise a pitched roof of 40°); the direction follows from the peak hour. Before, horizontal radiation was used, which was far too low for tilted panels, especially in autumn and winter.
- Batteries with standard Homey control: batteries that use the standard Homey battery control (target power), such as the official AlphaESS, Marstek Venus, SolaX and Zinvolt apps, are now controlled by the EMS. They are handed back to the device when the EMS stops or the battery is set to autonomous.
- Readme: Dutch and German readme added, with the list of supported devices.
Improved
- The consumption model falls back to a night-based estimate when too few hours are known.
- The discharge gate now runs in shadow mode: it only calculates and reports, nothing changes in behaviour yet.
Fixed
- Alfen ACE (Alfen.ProlineSingle): the EMS could not restart charging after a stop, because the charger reports no car presence. The EMS now also uses your car app’s plug status (if it has one) and retries a start every 15 minutes.
Thanks for the updated (test) version!
Two questions came up here. At this moment, I have around 1.5kW surplus PV for more then half an hour already, and a battery with only 19% charge (min SOC), so there is a good reason to start charging asap. According to the plan it will only start at 10:00AM, and EV charging later on. But what happens is that EV charging is recalculated and starts charging and battery discharge chosen, although there is not enough charge left. I’d expect the EMS to recalulate and start battery charging first and earlier. Also if I set battery charge mannualy via the flowcard “set EMS to battery charge” nothing happens. In my opinion battery charge should have prio if surplus PV is present, if no EV targets (ritjes) are present.
Secondly, for me personnaly I don’t want the battery allways to be used for EV charging, I have more value in using the battery for home use only. I can’t configure it to stay idle during EV charge. Ofcoarse I can make a flow to block battery discharging during EV charge, but I’d rather have the EMS regulating that.
Any thoughts?
Adding to this: Battery charging doesn’t start at all at this moment. according to plan it should, also manual it stay’s idle. 2.5kW PV power present.
Hello @Menno_De_Braak Unfortunately when trying to add the ultimate EMS device it gets stuck loading and when I press continue it won’t load any devices. Can you help me?
I’ve setup the app this week, ran into above issue but was able to complete the initialisation by progressing in this view to add the device and setup the functionality through the app settings.
Although I did setup the app, I did no enable the Ultimate EMS device. My understanding was that it would then record data and recommend actions, but not yet intervene.
This morning I found out that despite the Ultimate EMS device still being disabled, that it is actively overruling our setting on the EV charger.
Is that a bug in the app or is my assumption (Ultimate EMS device disabled = no active intervention) wrong?
When enabled, what is the advise regarding manual EV charging / forcing to charge due to a planned trip (and too low range)?
And how to set that when an EV is connected, solar power is available and minimum threshold of 1300W is met, that the EV charging based on solar will have preference over battery charging?
Hi Ted,
Your assumption is the intended behaviour: with the Ultimate EMS device switched off, the EMS only reads and does not send any command (EV, battery, boiler, thermostat). But I found why that isn’t what you see: the on/off switch only takes effect at the moment someone flips it. After pairing and after every app restart, the EMS starts in auto mode regardless of what the tile shows, and the tile is never updated to match. So a freshly paired device that looks “off” is actually running. That’s a bug on my side, and thanks for catching it. I’m fixing it so the tile and the real state always match and your choice survives a restart.
Until then, to stop it from touching your charger: switch the device on and then off again (that puts it in idle until the next app restart), or set the EV charge profile to “Off” / remove the charger from the EMS settings. Also, if you are still on 2.5.94, please update: several things have changed since, including the battery control that writes target power to ZinVolt.
For a planned trip, it’s best not to fight the EMS by changing the charger yourself, because with the EMS in auto it will set the charger again on its next cycle. Two ways to ask the EMS for it: the action “Plan EV trip” (departure time and target %), after which the EMS works backwards from the departure time and automatically switches to fast charging when that is needed to be ready in time (it also overrides the peak-hour block), or “Charge EV to % now” for an immediate top-up until that target is reached (stop it with “Stop extra EV charging”). You can also set the charge profile to Fast charge with “Set EV charge profile”.
Best regards, Menno
Ultimate EMS 2.5.111 (test version)
Battery
- The flow action “Set EMS mode” now really works for Battery charge and Battery discharge. A manual choice takes priority over the plan and the peak block.
- When the plan says “idle” but there is real solar surplus and no EV target, the battery now charges from that surplus instead of exporting it.
- New per-EV setting “Home battery for this EV”: Automatic (only when the battery is cheaper than the grid), Never(the battery only covers the house), or Only with free solar energy.
Boilers and SG Ready
- New optional “Power (W)” field per device. The EMS then only starts when there is roughly 70% of that power in surplus, counts its own consumption back while the device is on, and stops below about 45%. This fixes a 3 kW boiler switching on and off every minute. With several boilers, they no longer fight over the same surplus.
- Leave the field empty and everything works as before.
Solyx Nymo (experimental)
- The EMS can now steer a Nymo with the Solyx Energy app. It writes the net surplus to the Nymo’s surplus power value when there is more than 300 W of free surplus, and 0 when there is less than 100 W, or during peak hours.
- Set the Nymo to solar mode in the Homey app and add it as a boiler with 3000 W. Switch off your own Nymo flow, otherwise two things will write the same value.
- This has not been tested on real hardware yet, so feedback is very welcome.
EMS on/off tile
- The on/off switch of the EMS device now survives an app restart or update. The tile and the real state always match. Before, a newly paired device could show “off” while the EMS was still controlling.
Pairing wizard
- The wizard no longer gets stuck on “Checking…” or “Loading devices…”. After a time-out it shows a clear message and a retry button.
Energy tracking
- In the exclusion list (“Exclude devices in EMS energy tracking”), devices with the same name now get the last four characters of their ID behind the name, so you can tell them apart.
I also made a new webpage about how to connect your homey to SG-Ready boilers and heat pumps: SG Ready aansturen met Shelly | Ultimate EMS
