Home charging software limitations

[Shigura]

I have found it impossible to set my car to charge only between economically favourable times and still restrict the maximum charge level to 85%. Am I missing something? The software appears to want to combine charging times with a time for the car to be ready for use with the chosen level. This results in the car continuing to charge past the past the economically favourable window until the required level of 85% is reached. My solution is to restrict the charging time within the window to give a final charge of approximately 85% . Thus knowing that my car charges at roughly 7.5% of the battery capacity per hour, to raise the charge level from 70% to 85% I would need to restrict charging to two hours and so long as this is within my cheaper window then I have achieved my aim. But surely the car's software should be designed to achieve this simple task.

Sponsored

 

[DerekS]

I agree with you that this is highly overcomplicated.

I was able to achieve favorable time of use rates and a daily max of 85% as follows:

- Set the profile to minimum 25%, and your time of use window
- Create a timer for the earliest you might need the car each day (6am?) and set to 85%.

Setting both will keep your charging to 85% daily and avoid charging outside your favorable window. The one exception is if you plug in below the 25% minimum; the car will always charge right up to the minimum and ignore the time window.

 

[Jhenson29]

@Shigura it would be helpful if you could post what you want the final result to be. The we could help you with options to achieve that and explain limitations.

However, in general, it’s not possible to set both an maximum charge level and arbitrarily restrict the charging time window.

In practice, something close or that otherwise satisfies one’s needs can typically be found, but it’s hard to comment further without knowing your specific use case.

Please post your preferred target charge, your preferred charging times, and your EVSE size (charge rate; kW).

 

[JimBob]

The setup is kind of dumb. Charging is prioritized to the departure timer if set so it will ignore your TOU times so you may not get the benefit of cost reductions. If your TOU is close to your departure timer then it's not much of an issue.

Don't know if you have the home energy management system installed and use optimized charging, if it works around this.

 

[DerekS]

The setup is kind of dumb. Charging is prioritized to the departure timer if set so it will ignore your TOU times so you may not get the benefit of cost reductions

That's not my experience. By setting the TOU in the profile *and* the timer with 85%, I always got daily charges to 85% that never began outside my desired time window.

 

[dflohr]

I posted this sometime back when I went through this same thing on my RWD. May help. Agree, its convoluted.
https://www.dropbox.com/s/u9p0hz429al54hg/Charge Timer and Profile Setup2.pdf?dl=0

 

[JimBob]

That's not my experience. By setting the TOU in the profile *and* the timer with 85%, I always got daily charges to 85% that never began outside my desired time window.

In Porsche's own words if you want the cabin preconditioned. Go to about the 4:40 mark and listen to what she says.

 

[DerekS]

Whatever. I'm telling you what worked for me. Not interested in arguing.

 

[Jhenson29]

@JimBob @DerekS
Timers don’t completely ignore preferred times, but they are prioritized such that they allow charging outside of the preferred time if required.

For example: on Derek’s setup of a a timer at 85% at 6am with preferred times between 8pm and 3pm using a 9.6 kW EVSE, the timer can always charge within the preferred time.

However, if we change the preferred times to between 2am and 6am, it will start before the preferred times if plugged in below approximately 40%.

But preferred times aren’t completely ignored either. If we shift to 10pm to 2am, it will try to utilize that time.

And if we plug in with a higher SOC, it may reach the target within the preferred times, although note that it delays the start time as late as possible within the preferred time (added in orange)

 

[Shigura]

I agree with you that this is highly overcomplicated.

I was able to achieve favorable time of use rates and a daily max of 85% as follows:

- Set the profile to minimum 25%, and your time of use window
- Create a timer for the earliest you might need the car each day (6am?) and set to 85%.

Setting both will keep your charging to 85% daily and avoid charging outside your favorable window. The one exception is if you plug in below the 25% minimum; the car will always charge right up to the minimum and ignore the time window.

In my experience charging begins within the desired window but if 85% cannot be achieved within that then charging continues outside the window until 85% is achieved for the chosen departure time.

 

[Jhenson29]

In my experience charging begins within the desired window but if 85% cannot be achieved within that then charging continues outside the window until 85% is achieved for the chosen departure time.

That may be correct depending on your settings. The timer can absolutely cause charging outside of a preferred time.

 

[satchurator]

Can anybody who owns the Porsche Home Energy Manager comment on whether @Shigura ‘s goal is achieved any more easily by setting tariff configuration in combination with Optimized Charging on the car’s General Profile?

 

[Jhenson29]

@satchurator i know I don’t have the HEM and am thus not who you asked, but, there was a thread a while back about someone’s profile charging to 100% and it turned out to be that they were using a HEM.

https://www.taycanforum.com/forum/t...il-100-if-cable-plugged-in.10034/#post-144165

My takeaway is that the HEM just creates the preferred charge times, but everything else would stay the same. So, if you use either preferred times or optimized charging with a HEM, then you also need a timer to limit the target (otherwise, a profile has no limit in those cases) and then the timer would still override the profile if needed (else it doesn’t do what is being requested of it).

 

[satchurator]

@satchurator i know I don’t have the HEM and am thus not who you asked, but, there was a thread a while back about someone’s profile charging to 100% and it turned out to be that they were using a HEM.

https://www.taycanforum.com/forum/t...il-100-if-cable-plugged-in.10034/#post-144165

My takeaway is that the HEM just creates the preferred charge times, but everything else would stay the same. So, if you use either preferred times or optimized charging with a HEM, then you also need a timer to limit the target (otherwise, a profile has no limit in those cases) and then the timer would still override the profile if needed (else it doesn’t do what is being requested of it).

@Jhenson29 Yes, was asking any European HEM-owning folks out of curiosity (the HEM isn’t sold in the USA AJAIK). Ideally this stuff would all be configurable within the car/EVSE and ‘just work’.

 

[Jhenson29]

Yes, was asking any European HEM-owning folks out of curiosity

I think @Pozuelo has one.

Sponsored