Charging with the Amina S smart EVSE charger

Devices
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I’ve been testing the Amina S EVSE charger in combination with Homey for a month and time to share my first thoughts here. I’ve been sponsored the Amina S device, but Amina is not influencing this post.

Situation:

  • Homey Pro 2019 with advanced flows enabled.
  • Dynamic contract from Tibber.
  • Single phase 25A infra for an EVSE charger already in place due to previous chargers.
  • Experience with an OpenEVSE, SmartEVSE and Tesla TWA gen 3.
  • Measuring with HomeWizard Wi-Fi kWh meter 1-phase MID.
  • Driving a Hyundai Kona without “Blue Link” and a Tesla model 3.
  • I don’t use loadbalancing while I’ve splitted the three phases to have a dedicated phase per the two cars and the house.

Installation
The installation was really easy. It is divided into 3 steps:

  • Fixing the base to the wall. This is only plastic and therefore very light. Easy to hang properly.
  • Connecting and inserting the actual charging unit.
  • Setting up and close the housing.

Hanging the base and closing the lid are pretty straight forward but connecting the actual part is sometimes a bit fiddly. With the OpenEVSE and SmartEVSE I’ve build the units in complete before hanging and struggling with the thick and massive cables was a bit difficult. This proved to be very easy with the Amina S while I could test fit the length of the wiring, adjust, connect the wires and just click the charger into the housing. Connecting the charger cable itself was a bit more challenging while the preshrunk while the cable shoes are a tight fit.

Setting up
Linking the device to the Homey Pro was easy once understanding the principle. As the order of setting up the device wasn’t clear from the manual I had to open up the device (2 screws) and put the charger in pairing mode. These instructions are only on the homey installation page. My Homey Pro is placed in a closet (wood), 7 meters away from the charger and separated by an inner and outer wall. Connecting the Zigbeee went without any problems.

Charging for the first time
Once the device is set up charging is as straight forward as connecting the car and the charger starts. Controlling the charger from Homey is also pretty simple; there is a on/off switch in the app in which the device responds directly to.

Setting up the flow
As I already had a flow in place for the OpenEVSE I only needed to add this charger to the existing flow. For this I’ve used an advanced flow consedring the following steps:

  • Starting with a trigger from the Tibber app when the price is changed.
  • When the price contains “Expensive” the charger should be stopped, otherwise the charger should be started.
  • There is a check whether the charger state is on or off before sending the on or off command
  • There is a variable controller the max price from Tibber to control charging times more precise.
  • There is an override to enable the charger in the morning with freezing temperatures while the Hyundai otherwise won’t start the preheating.

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Considerations
The installation part was easy and beside having to try pairing the device a couple of times the whole process was done in a good hour or so.

The advantages for the Amina are

  • The charger is smart by itself and there is homey an integration straight from the supplier.
  • The installation is easy, though the preparations should be done by a certified electrician.
  • Everything works as expected.

The things I’m missing

  • There is no “integrated” place to put the connector back. This is now hanging loose and the rubber cap should be used to protect the connector from rain.
  • No readable temperature sensor.
  • Tesla open charger port button (this is obviously not something Amina should be fixing).

As for the OpenEVSE I’ve created an integration with a Fibaro implant. the effect and the controlling options are the same, but missing the extra information from the charger itself like the charging and connection state. The Fibaro smart implant utilizes a temperature sensor which I use for the Hyundai preheat fix, this I mis on the Amina.

As for the SmartEVSE there was no implementation for Homey. This I had to write the integration myself. Using the API from the SmartEVSE the result was the same as with the Amina, but obviously took a lot of time.

The Tesla TWA Gen 3 isn’t directly comparable. This is only suitable for Tesla drivers to utilize the benefits of this charger. The upside of this is that you can control who’s able to connect and controls the Tesla charger port. The downside is that there are no charging control options for the charger unit itself and has to be controller by the Tesla car itself with the available API’s.

Future integrations:
As I now have a basic implementation for controlling the charger I’m considering a couple of modifications for the near future:

  • Creating a physical override button to immediately start charging regardless of price.
  • Agenda integration for overriding “expensive” hours when needed.
  • Creating an authentication mechanism. (wifi presence, rfid, hidden button inside the house, usw, usw)
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Thanks for your insights! Really interesting read :smile:

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Do I understand correct that you have connected the Amina to only one phase?

I am also testing the Amina, one thing I ran into is that the Amina app is lacking a “1phase charging” card

Do you use the “3phase card” to set the current. That works?

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I’ve set the hardware switch to 25a (phase max) and don’t use a flow to balance or set a current.

I will test if this one works.

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Fkey, I’m not sure what the 3phase card is you’re referring to.
I’ve created a flow with the card called “Set maximum charging current to” and this works as expected. I’ve measured with the HomeWizard, set the max current to 20a to begin with and then set it to 10 while charging. Both work as expected.

AminaCurrent
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AminaFlow
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This is indeed the catd I was referring to.
I am using this in my surplus energy flow.

I have my Amina connected to all 3 phases.

In my case this result in all phases charging at 10A (so 30A in total)

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Update: After reinstalling everything I can now control current as expected.

Hi,

Been trying to optimize charging with Amina S and Homey for my Volvo C40 for the last few days and have experienced some fundamental limitations that I want to share.

New Volvo EVs are equipped with a setting in the main console inside the car where you can adjust the current limit in Amps. This is also a setting that is possible to adjust with Homey for the Amina S.

I initially created a flow where I adjusted the current for Amina S to a suitable setting that would keep a low enough current to protect the battery and minimize costs (in Sweden power companies charge by how many Amps you are using on average at peak usage) - while still fully charge the battery before I needed to leave for work.

However, soon enough I experienced that Homey was competing with the car. The settings Homey would push to Amina S would within seconds be overridden by the settings in the car console. I tried to combat this by updating the settings in Homey - but it became a small war between Homey and the car with current adjustments happening every few seconds.

In the end I had to reach out to Amina, who unfortunately had a very hard time just understanding the problem - and repeatedly reassured I just needed to set the settings up correctly in Homey. In the end I managed to get a hold of a charging technician at Volvo by contacting them through their developer portal. Volvo explained to me that the car will always overrides any smart charger settings, and that the console settings are not something you can disable and are not possible to be updated remotely through the Homey Volvo Car app e.g.

This means that if you have a Volvo car the Amina S and Homey integration is severely limited in usability. Volvo already has its own smart charging program with timers which makes it a bit of a redundancy to set up specific flows for this in Homey.

If you have a Volvo car I would thus lower my expectations on what Amina can deliver for you.

Other than that Amina has worked as expected and the design is sleek. I’m keeping the charger, albeit I’m a bit disappointed by the opportunities with Homey.

Best regards,

Alexander

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Hi Alexander

Strange, I have a volvo EX40, so that should be exactly the same car when you look at charging.

I am very satisfied with my flow to only charge using surplus energy. That flow is fully based on managing the Amperage via the Amina S.

And its working flawless.

BUT I did not set any amperage on the volvo (set to 30A while the Amina will do max (3x) 16A but normally much less. Homey is in full comtrol. So I guess that is in line with the advice you got from Amina

You can check out and download my flow here

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This makes me very puzzled. I checked your flow, and if you don’t have any conflicts with the Volvo there shouldn’t be any for me either. What have you set the physical dial in your Amina box to in terms of current limit?

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My meterbox breaker is 3x16A so that dial is set to position 5 (16A)

See also here for instructions on Amaina setting.

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After unplugging everything, including breaking power for Amina, and restarting everything, it now works as expected and as it is working for FKey. Thanks for sharing your set up which made me re-install everything!

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Good to hear!

Are you willing to share your flow? Could be usefull for others too!

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So the background is that Sweden has passed a law that all energy providers needs to charge by both the immediate load and by electric usage price. Where I live (Stockholm) the power company has made it so that the 3 days with the highest peak usage over 1 hour are charge by a fee of 8 euros per kW. The fee is half charge between 22:00 and 06:00. This is genereally when prices are the lowest too, so I try to charge the car between 22:00 to 06:00 with the lowest possible current to still be able to get the car fully charge (or to 90% in my usage case).

Therefore I set up a flow that every minute between 22:00 and 06:00 I calculate how many hours are left until 06:00 next morning and how many kWh I need to charge to get the car full. By diving the kWh by the hours I get how much kW I should be charging at.

After that I calculate how much power in kW are being delivered right now given the current in A across my 3 phases. I then use that ratio to divide the kW that I need to charge at and adjust the maximum current accordingly.

I’ve set a limit to charge no less than 6A and no higher than 16A as the car needs at least 6A to charge and my central limit is 20A and I don’t want to push it all the way if I’m also running some dishwasher or other power source. In the future I plan to get a energy dongle and load balance the maximum instead.

I’m attaching a screenshot of my flow. If anyone is interested I can go into detail and send a Flow Exchange.

/Alex

energy flow
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Dont fully understand how the energy prices are set up.

(Do they calculate per phase or the sum of all phases)

If they calculatr the sum of all phases I think it would be profitible to include 1phase charging..?

in your flow the lowest is 3x6A =18A

When you switch to 1phase charging you can even go back to 6A total charging current.

I have phase switching included in my flow, so you can check it there.

Be aware: switching does require a stop and start charging. And my experience is youneed a small 5sec delay otherwise the command is sometimes missed.

Maybe that saves you some extra fees!

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Sounds like you should “force“ the highest peakload for 1hour on 3 days and then stop after that hour.

And do the actual charging (major kw usage over multiple hours) on the other days :rofl:

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Sorry, I wasn’t clear enough. It’s not charged by how much current you are using but by how much power you are drawing in kW. The energy company measures the amount of kW every 15 minutes 24/7. At the end of the month they take the 3 hours with the highest power usage and average those 3 hours, so if you for example charge your car at 11 kW you will most likely have an average of 11 kW. The fee is then applied with 8 euro per kW. So if you charge at 11 kW then you pay 88 euro that month.

However, my flow normally manages to push the current low enough that the power is around 4 kW. And by charging at night the fee is half price. So that means a monthly cost of around 2 * 8 euro = 16 euro, which is saving me around 60 euro per month.

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Ah ok,

In that case switching (if the battery level is still high enough) to single phase charging would reduce the power to 1.3KW.

Reducing it to even 1.3x4=€5.2

Depends on your milage if you can make it, but extending your flow with Single phase charging is simple, so its worth the work I guess…

Just move the devision by 3 in your calculation to the right part of the flow. And if the calculation allows for 16A or lower switch to single phase charging.

If its hifher that 16A apply the devision by 3

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Great tip! However, I commute 200 km every day for work, so for me personally, there will never come a time when I need to charge at that low of a power lever.

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