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I heard solar mode is coming. When? How it will be implemented?
Sunny days are here :)

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Hey, Rado, the solar implementation is prepared for 1.7 release of the FW. We're working on some unrelated bugs and should release in the upcoming week(s). The setup of energy meter should be as for dynamic load balance -> the meter is right after the inlet of the grid. For solar to work, the meter has to show negative current values (current direction) or must be in the list of supported meters (which will be provided in the wiki).

The basic functionality of solar will have 4 modes: 1) fast charge, 2) full green, 3) eco and 4) eco+. The fast charge mode will perform just as dynamic load balance - the total consumption of the evse will not go over the max amps from grid value. However, the EVSE will use any solar surplus power that is available. 2) the full green mode will use only solar power, that is no power from grid will be drawn. For this mode to work, the minimum power from solar panels/inverter provided must be at least 6 Amps. 3) eco mode is a mix of fast charge and full green modes. Additional setting will be added which sets the maximum value of amps the EVSE will provide to the car when no or insufficient solar power is available. This means the EVSE will compensate the lack of solar power from the grid. When surplus of solar power (or total solar power generated) is higher than the value set in eco mode, the EVSE will provide all the solar power that is available. 4) eco+ mode is like a mix of full green and eco modes. Additional setting will be added which sets the minimum value of solar amps that must be present for the charge to initiate/continue. The range of this parameter will be 1 - 6 Amps. In this mode, if the solar power available is less than 6 Amps, but higher than the value set, the EVSE will charge at the maximum power of 6 A. However, if more solar power is available, the charging power will increase. That's the short description of the modes the 1.7 solar functionality will bring.

Additional logics that will be implemented: when solar power decreases mid charge, the 30 second counter will start which will end the charge if not sufficient power from solar is generated. After this countdown finished, the charging will only begin after 2 minutes after the solar power is once again available. If solar power decrease occurs when EVSE is not charging, no such delays will be active. The delays are also not considered when used with fast charge and eco modes.

That's a short description of the solar algorithm that is implemented in the 1.7 FW. Hope this answers your questions.
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Hello Daniellius,

I see one loop in this plan and that is using of a battery backup of solar power plant in residency areas. This can be plus or can cause also slight issues to your general setup.

Usually by the general setup of the solar plant - when there is consumption i.e. EVS charging, any slight "hiccup" in current production actually will be taken care of and solved by the inverter which highly possible will decide to use as primary first source the battery. ( depending of course on type of installation, type of inverter , its setup and if batteries are installed)

Here in Czech Republic 90% of homes having around 10kwp solar pannels together with 10kw battery backup.

Nevertheless I am not truly sure how actually in this case will act the smart meter, which is on first line of grid before inverter and just read up the "current flow" .( by the way not mentioning that if the PVE will be in regime of "off-grid" with banned delivery to grid - although PVE will be able to provide the energy, possibly wont get the info to smart meter about "over production" ? - ( ps. not sure need to check with my engineers)

So any consumption queries will actually be first handled by the inverter, who decides which way to take first / grid vs battery /.

It is very important and interesting topic to us - so I will talk to my engineers to provide you followup information on this. Im bit afraid that actually the whole setup and topic is slightly more complicated...

Thank you
Hi Intellio, thanks for the feedback and info provided. The only solar support for the 1.7 version of the FW will be provided through the meter readings, so energy export must be enabled for it to work. Off grid and installations where no export is allowed significantly burdens the solar integration as the Teltocharge device has to communicate with the inverter or other modbus capable device to get the solar generation readings. In this case, without the use of the meter, we would be able to observe the solar generation, however, we wouldn't be able to observe the usage of power after the inverter. In this case, if the total solar power generated is used by the premises of the installation, the additional power drawn by the EV would cause (depends on the situation) the current import from the grid and no control how the grid is overloaded would be made in this case. As with smart meters, the producers of inverters will most likely use their own individual modbus register maps and support for each inverter(manufacturer) would need to be implemented. At the moment, no such priority has been raised and it will not be (most likely) addressed with the 1.7 and 1.8 releases.

If you could provide more info regarding the most widely used installation setups, that would be beneficial for us to direct our focus for further development.

Sincerely, Danielius
@Danielius is it possible to control charging mode via ocpp? Did this addition expose any new data or controls over ocpp?
I've just installed the update, but haven't tried yet.
Charging mode is changed using the APP, no new controls over OCPP.

@Danielius First charging after FW update, brings issues with regular load balanced charging. Charging gets interrupted with no reason. House has no other major load, charging is limited in car to 7A, load balance limit on 20A and charging gets interrupted about every 20 minutes and restarts. Charging for an hour and already 3 interruptions. Something got broken with this update. Can FW be downgraded?


Hello @Rado just my point but I think you have the same issue what @Danielius already talked with you about 

Ref: Hey @danielszilagyi, thanks for the feedback. At first I was thinking about rounding issues for load balancing, however, the 7 A limit clears up a situation. Charging standard IEC 61851 says that the minimum charging current by PWM is 6 A. In our DLB algorithm, we set the current to 7 Amps. So in this case, if you set the current to 7 Amps, the PWM is 6 A / 0.6 = 11.667 -> 12 %. In this case the EV is drawing 5.8 Amps instead of 7 Amps, which seems to be the trait of the vehicle.  


So the question is why you have charging limit restricted in car one by 7A? Put in your car at least 11A - so you wont be on the minimum limit and potentially it is shutting off the charging.

That should work. if not then: 

Second option ( in my opinion ) try the other way.

Turn of the dynamic load balance

Set fixed value like 11A

Put car on max -it will take max 11A anyway- and that should work.

If this wont work there is definitely some other issue and Telto has to check SW.

Hey Rado, could you send a troubleshoot file to [email protected] with the issue described? We will look into it. In the meantime, the FW downgrade is not possible.
I didn't have this issue before, interruptions are still happening also if I remove the car limit. Will send you the details in the email.