EHU - Charging rate / time

[tonyhowell]

Hi All,

When charging my 2024 Beach from EHU the charging rate seems abysmally slow having taken the best part of a day to charge from around 40% to 100%

Checking the control panel from time to time, I saw around 3 amps going in.

Par for the course for a California or is something amiss?

Cheers

 

[Resfeber]

Hi All,

When charging my 2024 Beach from EHU the charging rate seems abysmally slow having taken the best part of a day to charge from around 40% to 100%

Checking the control panel from time to time, I saw around 3 amps going in.

Par for the course for a California or is something amiss?

Cheers

Bit of man maths
If your leisure battery is 75 Amps/hr when at 100% charge then at 40% charge it will be at 30amp/hrs charge.
The battery will need to charge from 30 amps to 75 amps, a total charge of 45 amps.
If the control panel charger rate of 3 amps/hr on the EHU charging is accurate (possible) then 15 hrs from 40% to 100% in theory.

So questions,
1) Is the battery really at 40%. A voltage reading is more accurate than % charge on the display.
This table from Loz is about the best guide to actual voltage reading on the display and the actual battery state.

Post in thread 'Leisure Batteries draining?'
https://vwcaliforniaclub.com/threads/leisure-batteries-draining.32887/post-388852

2) Again thanks to Loz, the alternator can charge a leisure battery at up to 40amps in an hour (but as battery nears 80% this rate has to fall either for regen braking and or battery cannot sustain this rate as it nears full) NB the display max’s out at 20 amps and shows >>20amps for charge rate)

Loz comments that the mains charger cannot manage much more than 13 amps/hr and quickly settles to 10amps/hrs

So with engine running
45 amps/hr to charge the leisure battery at 40% charge (based on voltage table)
would take 1.5 to 3 hrs.

Mains charger 10amps/hr would be 4.5hrs

Post in thread 'Leisure battery charge currents'
https://vwcaliforniaclub.com/threads/leisure-battery-charge-currents.30940/post-358957

So provided the battery was at 40%, the all day rate seems slow and May need the charger checked (as van is under warranty) but double check the table for voltage indicated and actual battery %.

Make sure the battery has settled for an hour with no drain or charge before taking a control panel reading

Only other issue was anything still running (like a fridge or lights to interior when you were charging on ehu?

 

[tonyhowell]

Thank you for the informative reply, very useful.

I have no demand plugged in, but I'll take some measurements over the next days/weeks see what I find.

 

[dspuk]

We see a lot of owners, especially newbies, pop on with worries about batteries - charging and whatnot.

In the main the answer is always "the van knows what it is doing there is nothing to worry about", even if we don't all know the exact rules VW engineers have put into the charging module maths.

In your case, I think @Resfeber has answered pretty comprehensively and in the main, the summary would be the van knows what it is doing and there is nothing to worry about.

I would add:
Why was the battery only 40%? Had you been away and off EHU/not driving for some time?
Could it be that it got to 80 and then trickled for an extended amount of time before it got to 100, which would be normal.

 

[Resfeber]

Thank you for the informative reply, very useful.

I have no demand plugged in, but I'll take some measurements over the next days/weeks see what I find.

Not too familiar with the Beach leisure battery set up but on mains the important issues would be
1) What voltage are you starting at so before plugging in and without the leisure battery having been used for around an hour what % does the table give based on the voltage reading.
2) As @dspuk comments what was used that took your leisure battery down to 40%. If this is a regular occurrence the battery life may be shorter it would be better to keep to 50% and above.

3) I don’t know if the Beach system has a “Max charge facility” icon in the control panel to ensure the leisure battery is boosted to 100% when the engine is on and the smart alternator is allowed to charge above the 80% limit in normal use.
Would be the quickest way to recharge the battery

 

[tonyhowell]

Not too familiar with the Beach leisure battery set up but on mains the important issues would be
1) What voltage are you starting at so before plugging in and without the leisure battery having been used for around an hour what % does the table give based on the voltage reading.
2) As @dspuk comments what was used that took your leisure battery down to 40%. If this is a regular occurrence the battery life may be shorter it would be better to keep to 50% and above.

3) I don’t know if the Beach system has a “Max charge facility” icon in the control panel to ensure the leisure battery is boosted to 100% when the engine is on and the smart alternator is allowed to charge above the 80% limit in normal use.
Would be the quickest way to recharge the battery

1) Unfortunately I didn't record the voltages prior to charging but will pay more attention in the future.

2) Good question - there was a Scosche USB charger plugged into the upper dash 12v socket - I've now removed it and will see if this was the cause - I can think of no other reason, I last hooked up the van around a month ago.

3) The Beach does have the "Max Charge" option on the control panel for when the engine is running.

These are all good points, hopefully the USB charger was the drain cause.

 

[Resfeber]

1) Unfortunately I didn't record the voltages prior to charging but will pay more attention in the future.

2) Good question - there was a Scosche USB charger plugged into the upper dash 12v socket - I've now removed it and will see if this was the cause - I can think of no other reason, I last hooked up the van around a month ago.

3) The Beach does have the "Max Charge" option on the control panel for when the engine is running.

These are all good points, hopefully the USB charger was the drain cause.

Think you have identified the culprit