Charging to 80%

[Simon 19662021]

I picked the car up yesterday,I have a EO charger and I am on Ocypus Go,so how do I set the charge to 80%,it just keeps charging for the 4 hour slot?

 

[mystreet]

The car and or the EO will not charge to a %.

Only thing I can think of is to set the inital charge status before you start in the EO app. Roughly 10% charge is 16 miles. Therefore 80% charge is 128 miles.

So if you start charging at 50 miles left on the GOM you need to put in 78 miles, set the initial state to 82 miles. Aldi make sure you have selected the correct car in the settings

 

[JodyS21]

There is no way for any charger to know what the state of charge is in the car, therefore it is not possible for any charger to automatically charge the car to a set SOC. This is because our car doesn't support this/have an API.
Your only way to achieve charging it to 80%, is to manually look at how much you want to add to the car when you plug it in, then adjust the charging to just add that amount (if the charger you have supports doing that). You'd have to do this every time you charge it.

All you can do automatically via a "smart" charger, is effectively set a minimum amount of charge that you want the car to have once the charge has completed.

 

[LiamWhales]

I have managed to get my charger setup in order for it to only charge the car to 80% but it is not a straight forward process and this probably won't be of much use to you but thought I'd share anyway.

I've got Torque Pro installed on my phone and a bluetooth dongle in the obd2 port so I can pull SoC while I'm in the car. The log files from this get sent over to my home automation system so that then is made aware of the last known state of charge.

I then have my granny charger on a smart plug with energy monitoring so I can control when it charges and measure how much energy is delivered to the car. It then cuts off when it's delivered the amount of electricity needed to get it up to 80%.

 

[Kithmo]

I have managed to get my charger setup in order for it to only charge the car to 80% but it is not a straight forward process and this probably won't be of much use to you but thought I'd share anyway.

I've got Torque Pro installed on my phone and a bluetooth dongle in the obd2 port so I can pull SoC while I'm in the car. The log files from this get sent over to my home automation system so that then is made aware of the last known state of charge.

I then have my granny charger on a smart plug with energy monitoring so I can control when it charges and measure how much energy is delivered to the car. It then cuts off when it's delivered the amount of electricity needed to get it up to 80%.

You do know you're supposed to charge the battery to 100%, then some, to balance the cells once a month ?
It's in the manual.

 

[LiamWhales]

Yeah I am aware and I will periodically do that but I also can see the Cell Inbalance and judge when it needs doing. Since I'm only slow charging, the cells remain well balanced and I've only done 1 balancing charge in 5 months.

 

[AbuG]

I have managed to get my charger setup in order for it to only charge the car to 80% but it is not a straight forward process and this probably won't be of much use to you but thought I'd share anyway.

I've got Torque Pro installed on my phone and a bluetooth dongle in the obd2 port so I can pull SoC while I'm in the car. The log files from this get sent over to my home automation system so that then is made aware of the last known state of charge.

I then have my granny charger on a smart plug with energy monitoring so I can control when it charges and measure how much energy is delivered to the car. It then cuts off when it's delivered the amount of electricity needed to get it up to 80%.

Which automation system do you use? And how do you let it know the SOC?

I am currently checking via OBD then manually setting an off timer, but if it can be automated that would be useful.

 

[LiamWhales]

I use a combination of EMON cms and openhab, I use EMON for tracking/logging and OpenHab for the interface.

I have Torque Pro set to log to files, then this file is sync'd to my google drive using an app called drivesync. Then I have a python script on my Emon host that checks for new files, reads the contents and uploads the data to Emon.

To get the current state of charge I take the plug's total energy use when I last got a file update vs what it is now and add that onto the last know SoC.

 

[Lovemyev]

I picked the car up yesterday,I have a EO charger and I am on Ocypus Go,so how do I set the charge to 80%,it just keeps charging for the 4 hour slot?

It’s a bit “Caveman” - but you can get near to a SOC of 80% if you can set a finish time on your App.
I have a Rolec dumb charger with a Sonoff Wi - Fi relay installed that allows me to set a timed schedule on my phone that will allow charging by using my cheaper “Off - Peak” tariff.
If I only want to charge to around the 80% mark, I will plug in and check what the car reports it will take to reach 100% and the time factor it will take to achieve this figure.
This car be viewed via the drivers door window when the car starts to pull a charge.
On a 7.00 kw wall box, you are going to be adding about 25 miles of range for each hour the car is in charge.
It is easy to work out how long the car needs to be on charge to hit 80% and then set the end time of the controlled charge to end there on the App.
It sounds a bit of a “Faff” but it almost becomes second nature after a while.
I use this method a lot when not wanted to charge / balance to 100% when I know the trips I have planned over the next few days are likely to be only very short.

 

[Mike]

I believe the OVMS developers for the MG are working on this, though I haven’t installed the build yet.

 

[chowbenter]

You do know you're supposed to charge the battery to 100%, then some, to balance the cells once a month ?
It's in the manual.

I'd forgotten about this charging to 100% once a month to balance the cells so I'll charge it today to 100% & see if the MG symbol stays solid light after it reaches 100%. Since we don't use the car everyday I've always left it charged between 70%-80% since we got it.

 

[Coulomb]

It is easy to work out how long the car needs to be on charge to hit 80% and then set the end time of the controlled charge to end there on the App.

How does the app end the charge? Which app?

I hope it doesn't end the charge by opening the EVSE relay under a 7 kW load driving a PFC stage (huge inductor will cause a massive arc on turn-off). Hopefully, it stops it at the car end, or if at the EVSE end it drops the control pilot first before opening the relay.

 

[Lovemyev]

How does the app end the charge? Which app?

I hope it doesn't end the charge by opening the EVSE relay under a 7 kW load driving a PFC stage (huge inductor will cause a massive arc on turn-off). Hopefully, it stops it at the car end, or if at the EVSE end it drops the control pilot first before opening the relay.

The “Sonoff Wi-Fi” relay only controls the low voltage signal to the car via the communication device in the dumb wall box.
When commanded, it sends a signal to pull in the contractor in the wall box
It is not switching the full 7kw load from the supply.
The “App” is a free to download software available from the App Store etc.
It been produced to control the Sonoff range of switching devices.
It gives you the ability to set start and finish times from your phone etc.
When plugging in the ZS EV and the charge commenced, the dash panel will report the SOC of the battery and give a time of how long it will take to hit a full 100% of charge.
If you only want to charge to say 80% you can finish the charge at a time to suit your requirements.
Working on the theory that a 7kw wall box will put roughly about 25 miles of range into the battery every hour.
It is fairly easy to control the finish time to achieve a lower SOC of a chosen %.

 

[JodyS21]

The “Sonoff Wi-Fi” relay only controls the low voltage signal to the car via the communication device in the dumb wall box.
When commanded, it sends a signal to pull in the contractor in the wall box
It is not switching the full 7kw load from the supply.
The “App” is a free to download software available from the App Store etc.
It been produced to control the Sonoff range of switching devices.
It gives you the ability to set start and finish times from your phone etc.
When plugging in the ZS EV and the charge commenced, the dash panel will report the SOC of the battery and give a time of how long it will take to hit a full 100% of charge.
If you only want to charge to say 80% you can finish the charge at a time to suit your requirements.
Working on the theory that a 7kw wall box will put roughly about 25 miles of range into the battery every hour.
It is fairly easy to control the finish time to achieve a lower SOC of a chosen %.

Just curious, aren't going to do this myself - though I have several different sonoff modules for other uses.

How are you intercepting the low voltage signal you talk of - have you taken your charge unit apart? what wire is it on the plug?
Is it simply make or break this wire connection to control it?

 

[notdodgy]

The “Sonoff Wi-Fi” relay only controls the low voltage signal to the car via the communication device in the dumb wall box.
When commanded, it sends a signal to pull in the contractor in the wall box
It is not switching the full 7kw load from the supply.
The “App” is a free to download software available from the App Store etc.
It been produced to control the Sonoff range of switching devices.
It gives you the ability to set start and finish times from your phone etc.
When plugging in the ZS EV and the charge commenced, the dash panel will report the SOC of the battery and give a time of how long it will take to hit a full 100% of charge.
If you only want to charge to say 80% you can finish the charge at a time to suit your requirements.
Working on the theory that a 7kw wall box will put roughly about 25 miles of range into the battery every hour.
It is fairly easy to control the finish time to achieve a lower SOC of a chosen %.

I have a 16amp Sonoff inline with an external socket that I can use with a granny charger. As well as scheduling, it records power used and it can be configured to turn off when the current drops to a set level.
Shame they don't do a 32amp / 7kW version.

 

[notdodgy]

I use a combination of EMON cms and openhab, I use EMON for tracking/logging and OpenHab for the interface.

I have Torque Pro set to log to files, then this file is sync'd to my google drive using an app called drivesync. Then I have a python script on my Emon host that checks for new files, reads the contents and uploads the data to Emon.

To get the current state of charge I take the plug's total energy use when I last got a file update vs what it is now and add that onto the last know SoC.

An interesting work around.
I wish there were a simple way to get the state of charge without plugging in a charger or an OBD2 device/app.

I have an Ohme charger and observed that the power taken by the car drops from 7kW to 3.5kW when it reaches 97% charge.

Someone kindly provided me with the information on how to read the status and start / stop charging remotely - (it's not yet an official API).

I have programmed an ESP32 controller to connect over WiFi and check the charge status at intervals.


I can now use it to charge to 97% (power dropping to 3.5kW) and stop, or complete a balance charge.
It also emails me with updates.

 

[Deleted member 2439]

I have a 16amp Sonoff inline with an external socket that I can use with a granny charger. As well as scheduling, it records power used and it can be configured to turn off when the current drops to a set level.
Shame they don't do a 32amp / 7kW version.

There are some concerning videos on YouTube showing 16amp Sonoffs are not quite man enough! I use one to control my immersion heater (on/off) under Alexa voice control - however, I get the Sonoff to control a proper contactor which is able to carry the full current for a long period. I also recall that the Sonoff only switches the live? So that‘s a concern.

 

[notdodgy]

There are some concerning videos on YouTube showing 16amp Sonoffs are not quite man enough! I use one to control my immersion heater (on/off) under Alexa voice control - however, I get the Sonoff to control a proper contactor which is able to carry the full current for a long period. I also recall that the Sonoff only switches the live? So that‘s a concern.

I have a number of the smaller inline ones and some socket ones, which I only use for lighting / low power use.

The POWR2 is rated at 16 Amps and the charger draws 10, so a reasonable amount of headroom.
I am more concerned about the spring loaded connectors than the relay, I may take a soldering iron to it.

 

[Lovemyev]

Shame they don't do a 32amp / 7kW version.

The 16 amp rated “Sonoff” relay is over rated for the job that it is performing in my 5 year old dumb Rolec unit.
The relay itself, only requires a 240 volt line & negative conductor wired into the incoming side of the relay to power it, easily found inside the unit.
On the out going side ( switched ) the signal wire to the coms device is interrupted by the relay.
This is a very low load of around 1 - 2 amps and therefore well inside of the 16 amp rating of the “Sonoff”.
When the command from the “App” is sent to commence the charge, it orders the communication module to pull in the heavy contactor that carry’s the heavy 7kw load.
The “Shelly” relay works in a very similar way.
I have been using this system to control my wall box for over a year now and it is a fantastic work around for the problems of delayed charging on cheaper off peak electric.
You can buy a relay that WILL switch the heavy supply load of 7kw’s - but they are expensive.
I guess it depends on your set up which is the best to suit your needs really ?.
The relay only cost about £15 if I remember correctly and about 30 mins to wire into the unit, with some kind help from some fellow members.