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Discussion Starter · #1 ·
Has anyone had their car decided to interrupt a charge on their home charger ? I was charging and expected it to go to completion (35-36kWh) but for some reason it stopped at 24.5kWh (according to Leafspy). It's not happened before, and i'm a bit puzzled.

What i did; i disconnected the 12V (as the GoM seemed too low for 24.5kWh) and reconnected which led to a more reflective GoM estimate. I then put the 12V on charge with my smart charger - i wondered whether it might be a low 12V leading to charge interruption ? Charged battery overnight and all worked fine this morning, but wondering whether it might happen again or what the cause might have been. Any thoughts ?
 

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The DC/DC converter in the car should be keeping the 12v battery topped up during traction battery charging - when actively charging it around 14.4v, when maintaining it around 13.0v. So once charging has started a weak 12v battery should not in theory lead to the traction battery charging aborting part way through.

Is there any possibility your house had a momentary brownout that was enough to stop the car charging ?

Do you have charge end notifications enabled in the Nissan app ? If you do, you will get an alert when charging stops, including abnormal stops, which could be useful to detect when this is happening.
 

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GOLF GTE PHEV
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Has anyone had their car decided to interrupt a charge on their home charger ? I was charging and expected it to go to completion (35-36kWh) but for some reason it stopped at 24.5kWh (according to Leafspy). It's not happened before, and i'm a bit puzzled.

What i did; i disconnected the 12V (as the GoM seemed too low for 24.5kWh) and reconnected which led to a more reflective GoM estimate. I then put the 12V on charge with my smart charger - i wondered whether it might be a low 12V leading to charge interruption ? Charged battery overnight and all worked fine this morning, but wondering whether it might happen again or what the cause might have been. Any thoughts ?
Did you have the charge timer set, because 24.5kw is what I get during the 4hour Octopus Go 5p rate?
 

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2012 24kw upgraded to 40kw
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Discussion Starter · #5 ·
The DC/DC converter in the car should be keeping the 12v battery topped up during traction battery charging - when actively charging it around 14.4v, when maintaining it around 13.0v. So once charging has started a weak 12v battery should not in theory lead to the traction battery charging aborting part way through.

Is there any possibility your house had a momentary brownout that was enough to stop the car charging ?

Do you have charge end notifications enabled in the Nissan app ? If you do, you will get an alert when charging stops, including abnormal stops, which could be useful to detect when this is happening.
Thanks, i was clutching at straws with the 12V battery guess - as i've experienced and read of the grief that these can cause. Also, i thought that the 12V charging happened at the end of the charging session (rather than during) ?

I don't use the Nissan app - it was too clunky when i looked at it initially and i've not revisited it. Also, we tend not to use the charging or climate timers (routines are too variable...).

It happened sometime on Sunday afternoon and has not happened before - it could have been a brownout due to everyone putting their Sunday roast on :) I tend to charge overnight for convenience rather than cheap tariff, and sometimes use the granny or the chargepoint.

For now, i'll see whether it happens again and hope that it doesn't !
 

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Thanks, i was clutching at straws with the 12V battery guess - as i've experienced and read of the grief that these can cause. Also, i thought that the 12V charging happened at the end of the charging session (rather than during) ?

I don't use the Nissan app - it was too clunky when i looked at it initially and i've not revisited it. Also, we tend not to use the charging or climate timers (routines are too variable...).

It happened sometime on Sunday afternoon and has not happened before - it could have been a brownout due to everyone putting their Sunday roast on :) I tend to charge overnight for convenience rather than cheap tariff, and sometimes use the granny or the chargepoint.

For now, i'll see whether it happens again and hope that it doesn't !
Sounds like a fault in the CANBridge or its software given that the GOM reading was "too low" and that is certainly influenced by the CANBridge software. I guess that it will be too difficult to access the charge logs for Muxsan to report against.
 

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Discussion Starter · #7 ·
Sounds like a fault in the CANBridge or its software given that the GOM reading was "too low" and that is certainly influenced by the CANBridge software. I guess that it will be too difficult to access the charge logs for Muxsan to report against.
Yes, i wondered about that though it's charged several times and not done this before. There's certainly issues with how the CANbridge software reports through the GoM and bars on the dash. It only works well if charged to full - if partially charged then all the bars light up but this isn't reflecting the SoC. I emailed them about it a while ago but had no response, and was hoping that it would eventually be fixed via an update. Perhaps using a Dala version of the firmware might become a better alternative...
 

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Thanks, i was clutching at straws with the 12V battery guess - as i've experienced and read of the grief that these can cause. Also, i thought that the 12V charging happened at the end of the charging session (rather than during) ?
The DC/DC converter for the 12v battery seems to run in one of two modes when the car is on or the traction battery is charging - "actively" charging the 12v battery, where it will take the voltage up to about 14.4v, and "maintaining" the battery - once it decides it is charged it drops back to 13.0v - this is low enough that a fully charged 12v battery will not draw any current to charge, but high enough that if any 12v systems place a load they will not discharge the battery either.

Approximately 12.7v to 13.5v is a sort of neutral dead band (or rubber band) range for a fully charged 12v Lead Acid battery - neither charging or discharging the battery.

My point is if the traction battery is charging the DC/DC converter will be maintaining the 12v system at least at 13.0v, so even with a weak battery 12v loads such as the contactors won't pull the voltage below 13.0 volts once the contactors have closed.

So a weak 12v battery could easily cause the start of a charge attempt to fail (if it can't supply the contactor pull in current for example) but once it has bootstrapped itself it should keep going.
 
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