Trying to understand battery usage - help?!

[CampervanOwner]

I’ve been trying to educate myself (& struggling) on the battery level of our new 6.1 Ocean.

I’ve seen various versions of the ‘State for Charge’ tables. Does the percentage column correspond in any way to the number of blue highlighted bars on the battery level showing on the console? If so, our console was displaying 11.9v but just 2 blue bars. Isn't 11.9v around a 40% State of Charge (therefore, 4 bars)?

Regardless, we took the van for a drive purely to top up our battery levels (no hook up available). Was this right to do based upon 11.9v (or 2 'bars') or could we have left it longer?

This disappointed me as we’d dropped from 12.8v (9 bars) when we arrived on campsite to 11.9v only 48 hours later. Is this normal as it’s waivered my confidence with trying to go without hook up? I thought we'd last more than 2 days.

Our amp usage (?right word?) waivered between -1a and -4a. We had the fridge on level 3 and only used the lights for maybe an hour both nights. It was quite warm too.

I’d appreciate any guidance (in layman’s terms!). Thank you

 

[Stu@rt]

The blue bars are a bit of a novelty and you should probably take more notice of the voltage than the pictures. I don't think you have anything to worry about with what you describe, its sounds rather regular. 12.8v is pretty much fully charged. I understand that your fridge and diesel heater will cease to function at 11.5V but I have never let the batteries get that low. Plenty on here suggest you should be able to achieve 3-4 days with conservative use, but all charts I see suggest a risk of damage if you let them get into the "red area"

 

[yossarian]

Does the percentage column correspond in any way to the number of blue highlighted bars on the battery level showing on the console?

Yes, on the 6.1 these bars are pretty accurate if the system is working as designed. You'll hear a lot of chatter around only voltage being accurate but this is not true of a 6.1 that's working properly.

I thought we'd last more than 2 days.

I have a similar van and I'd expect 3 - 4 days. Your batteries may not be in the best of health. Do you plug in your EHU once every 4 to 6 weeks for at least 24 hours? What model year is your van?

 

[CampervanOwner]

Yes, on the 6.1 these bars are pretty accurate if the system is working as designed. You'll hear a lot of chatter around only voltage being accurate but this is not true of a 6.1 that's working properly.


I have a similar van and I'd expect 3 - 4 days. Your batteries may not be in the best of health. Do you plug in your EHU once every 4 to 6 weeks for at least 24 hours? What model year is your van?

I should hope the batteries are in good health as I only bought the van in March! It's a daily driver and we plug into EHU on campsites once or twice a month.

I can't work out why the batteries drained so quickly as we were conservative with our use. I was expecting at least 3 days off EHU

 

[Steve1]

I’ve been trying to educate myself (& struggling) on the battery level of our new 6.1 Ocean.

I’ve seen various versions of the ‘State for Charge’ tables. Does the percentage column correspond in any way to the number of blue highlighted bars on the battery level showing on the console? If so, our console was displaying 11.9v but just 2 blue bars. Isn't 11.9v around a 40% State of Charge (therefore, 4 bars)?

Regardless, we took the van for a drive purely to top up our battery levels (no hook up available). Was this right to do based upon 11.9v (or 2 'bars') or could we have left it longer?

This disappointed me as we’d dropped from 12.8v (9 bars) when we arrived on campsite to 11.9v only 48 hours later. Is this normal as it’s waivered my confidence with trying to go without hook up? I thought we'd last more than 2 days.

Our amp usage (?right word?) waivered between -1a and -4a. We had the fridge on level 3 and only used the lights for maybe an hour both nights. It was quite warm too.

I’d appreciate any guidance (in layman’s terms!). Thank you

2 Days is about right if you are using the battery for the fridge lights and a bit of charging particularly when it's hot so fridge is working hard. The most accurate reading for the voltage is when no current is being drawn (or almost none) so wait until fridge is on its off cycle and turn off any chargers for phone briefly and read voltage (current should be almost zero at that point). If it is below 12.0V definitely run engine to charge, lead acid batteries will start to be ruined when discharged much below 12V. So you did the right thing !

 

[Californication69]

The best way to read the battery display.

Pop to B&Q
Purchase a dustbin, with lid.
Turn the lid upside down on the bin.

Get a nice spatchcock chicken.
Cook on BBQ pref a 3 burner with middle burner switched off.
Around 190 degrees for 1 hour for a medium chicken.
Eat the chicken.
Set the bones out and let them dry for 3 days.

When the bones are dry, throw them on the lid.
Read the corresponding chicken bones on the lid and this will tell you how many hours & minutes you have left in the battery on a particular day.
And also knows exactly how much power you are thinking of going to need over the next 2 days.


*NB
Sorry. I am being very silly.

 

[dspuk]

If it's that important to you to go off EHU you should look at a solar panel to give you that extra peace of mind. We have one and did an easy 5 days at a festival last year. In summer and good location you can theoretically go indefinitely with just a 150 panel.

3 days is the general consensus with fully charged batteries via home hook up before you go away and max charge when heading to the site, and then "normal" usage.

Make sure the fridge is on before you go and when hooked at home as well to avoid the pull when going down to temperature as it can draw around -9 to get there.

 

[yossarian]

batteries are in good health as I only bought the van in March

This is unfortunately quite a minefield. Dealers don't necessarily look after the batteries and VW themselves have been known to put vehicles in storage for some time if they run into a problem with components. Data like battery internal resistance and state of health are available on the OBD if you have OBDeleven or similar but i wouldn't purchase one just for that.

It's a daily driver and we plug into EHU on campsites once or twice a month.

Your batteries should be ok then. Maybe look into @dspuk 's suggestions.

I can't work out why the batteries drained so quickly as we were conservative with our use. I was expecting at least 3 days off EHU

Your control panel amps don't sound excessive however many people in the same predicament have discovered things plugged into the various 12V outlets or the inverter (or the inverter on due to a microswitch problem). There are 3 x 12V outlets in the back: roof, bench and boot area, all worth a quick check. The USB in the kitchen too. The 12V outlets on the dash might be wired to either bus. The usb-C outlets should be powered by the infotainment & vehicle bus (ie not likely to be a culprit).

Edit: your vehicle should detect and report problems related to a blown cube fuse so this is unlikely to be your problem.

 

[WelshGas]

I’ve been trying to educate myself (& struggling) on the battery level of our new 6.1 Ocean.

I’ve seen various versions of the ‘State for Charge’ tables. Does the percentage column correspond in any way to the number of blue highlighted bars on the battery level showing on the console? If so, our console was displaying 11.9v but just 2 blue bars. Isn't 11.9v around a 40% State of Charge (therefore, 4 bars)?

Regardless, we took the van for a drive purely to top up our battery levels (no hook up available). Was this right to do based upon 11.9v (or 2 'bars') or could we have left it longer?

This disappointed me as we’d dropped from 12.8v (9 bars) when we arrived on campsite to 11.9v only 48 hours later. Is this normal as it’s waivered my confidence with trying to go without hook up? I thought we'd last more than 2 days.

Our amp usage (?right word?) waivered between -1a and -4a. We had the fridge on level 3 and only used the lights for maybe an hour both nights. It was quite warm too.

I’d appreciate any guidance (in layman’s terms!). Thank you

You have 2 x 75 amp batteries giving a total of 150 amp hrs.
Good practice for AGM leisure batteries is not to run them below 50% capacity which gives you a total of 75 amp hours usable power.

You stated that the display showed between -1 and -4 amps and the ambient temperature was quite warm.

When the display showed -1amp , probably due to just lights you could have run them for 75 hrs ( 3 days ).

When the display showed -4 amps this was the fridge running. So at that current draw you would have had 20 hrs usage. Fortunately the California compressor fridge runs intermittently to maintain the temperature BUT the warmer the ambient temperature the more often it will run.
In winter the fridge might only run for 10 mins/hr so using 4/6 amps/ hr = 0.7 amps/hr.
So your battery will last a 100 hrs.
In a hot summer the fridge may run for 30 mins/hour = 2 amps/ hr so your battery will only last 35 hrs.

NB: because of the Smart Alternator system the leisure batteries are only charged to 80% actual capacity although the Control Panel shows 100%.
Use the Max Charge button on the dash an hour or two before site arrival and this will ensure the Leisure Batteries are fully charged

 

[CampervanOwner]

2 Days is about right if you are using the battery for the fridge lights and a bit of charging particularly when it's hot so fridge is working hard. The most accurate reading for the voltage is when no current is being drawn (or almost none) so wait until fridge is on its off cycle and turn off any chargers for phone briefly and read voltage (current should be almost zero at that point). If it is below 12.0V definitely run engine to charge, lead acid batteries will start to be ruined when discharged much below 12V. So you did the right thing !

Thanks for the reassurance that 2 days isn't unusual. We didn't use anything other than cool the fridge and 1 hour of lights for 2 nights (plus 1 phone charge to be accurate). I'm really curious how others manage 3-5 days?? It was quite warm granted.

Does running the engine whilst static still give the leisure batteries some charge then? I've seen comments agreeing with that, yet others say that doesn't work. I'm confused!

 

[CampervanOwner]

@Stu@rt - you say the blue battery bars on the console are "a bit of a novelty"
@yossarian - you say the bars are "pretty accurate"

Thanks both for your reply, but who's right?!

 

[dspuk]

@Stu@rt - you say the blue battery bars on the console are "a bit of a novelty"
@yossarian - you say the bars are "pretty accurate"

Thanks both for your reply, but who's right?!

They both are.

 

[dspuk]

Thanks for the reassurance that 2 days isn't unusual. We didn't use anything other than cool the fridge and 1 hour of lights for 2 nights (plus 1 phone charge to be accurate). I'm really curious how others manage 3-5 days?? It was quite warm granted.

Does running the engine whilst static still give the leisure batteries some charge then? I've seen comments agreeing with that, yet others say that doesn't work. I'm confused!

I’ve never heard of anyone getting 5 days with the fridge on.

 

[CampervanOwner]

You have 2 x 75 amp batteries giving a total of 150 amp hrs.
Good practice for AGM leisure batteries is not to run them below 50% capacity which gives you a total of 75 amp hours usable power.

You stated that the display showed between -1 and -4 amps and the ambient temperature was quite warm.

When the display showed -1amp , probably due to just lights you could have run them for 75 hrs ( 3 days ).

When the display showed -4 amps this was the fridge running. So at that current draw you would have had 20 hrs usage. Fortunately the California compressor fridge runs intermittently to maintain the temperature BUT the warmer the ambient temperature the more often it will run.
In winter the fridge might only run for 10 mins/hr so using 4/6 amps/ hr = 0.7 amps/hr.
So your battery will last a 100 hrs.
In a hot summer the fridge may run for 30 mins/hour = 2 amps/ hr so your battery will only last 35 hrs.

NB: because of the Smart Alternator system the leisure batteries are only charged to 80% actual capacity although the Control Panel shows 100%.
Use the Max Charge button on the dash an hour or two before site arrival and this will ensure the Leisure Batteries are fully charged

So helpful, thank you. The explanation about having 75amps of usable power makes complete sense.

Being objective therefore, how is it possible for those without solar to obtain the often-claimed 3+ days' use?

Lastly, you say the control panel can show a misleading 100%. Where would I see this? I'm still trying to work out whether the percentage references are depicted by the blue battery bars.

Thank you

 

[yossarian]

If you use a desktop computer to access the site or you rotate your phone to landscape mode you can usually read the poster's profile which might correlate with what sort of opinion they might have of van systems.

Here's what your profile looks like:

 

[Lambeth Cali]

We definitely used to get 5 days with the fridge on. We used go to Roundhill in the New Forest for 5 days every year. We used to lose 10% a day. Must have gone below 50% dozens of times but then charged up on the drive home.

We have just done Friday night to Monday evening with the fridge on. They never went below 12.1V. Our batteries are 16 years old. Maybe the fact we have always used our batteries a lot made them last longer.

I honestly think batteries are enormously variable.

Btw to get voltage readings you need not to have anything turned on.

 

[Lambeth Cali]

Flat 2008 Leisure Batteries revived, sort of

Last night I moved our van to our drive to pack for our first trip of the year, and first I think since last August. The leisure batteries were showing flat. Well they showed 40%, 10% then 0% over less than a minute after the 100 metre drive. I’ve plugged them in for 24 hours and it will be...

vwcaliforniaclub.com

 

[Steve1]

Thanks for the reassurance that 2 days isn't unusual. We didn't use anything other than cool the fridge and 1 hour of lights for 2 nights (plus 1 phone charge to be accurate). I'm really curious how others manage 3-5 days?? It was quite warm granted.

Does running the engine whilst static still give the leisure batteries some charge then? I've seen comments agreeing with that, yet others say that doesn't work. I'm confused!

Yes it does. You would need to use the max charge( or on older vans use the seat heater on level one) to make the smart alternator go full charge. We normally manage the first 2 days without starting the car then we do 45 mins charge with the car standing each day to top up from then on. It definitely works the alternator will charge the battery quickly. Many don't like the noise or environmental impact etc. etc. but it works fine. We only do off hookup when needed it's much easier to charge from power but when we do go without hookup we always use this method. If you pick a time in the noisier part of the day no-one is bothered by it.

And by the way, I fitted out batteries brand new, and have only ever got about 2 days. In the summer the fridge drains it and in the winter the heater over night. But some people can get longer by not using the equipment as much. If you set the fridge warmer and don't really use it as a fridge, just a drinks cooler and don't use the heater in winter I expect you could last longer.

If you really want to do lots of camping without hookup then solar may well be your answer. For the odd night I would run the van to charge !

 

[CampervanOwner]

Yes it does. You would need to use the max charge( or on older vans use the seat heater on level one) to make the smart alternator go full charge. We normally manage the first 2 days without starting the car then we do 45 mins charge with the car standing each day to top up from then on. It definitely works the alternator will charge the battery quickly. Many don't like the noise or environmental impact etc. etc. but it works fine. We only do off hookup when needed it's much easier to charge from power but when we do go without hookup we always use this method. If you pick a time in the noisier part of the day no-one is bothered by it.

And by the way, I fitted out batteries brand new, and have only ever got about 2 days. In the summer the fridge drains it and in the winter the heater over night. But some people can get longer by not using the equipment as much. If you set the fridge warmer and don't really use it as a fridge, just a drinks cooler and don't use the heater in winter I expect you could last longer.

If you really want to do lots of camping without hookup then solar may well be your answer. For the odd night I would run the van to charge !

Thanks for the reply. I feel more reassured knowing 2 days' use is not uncommon off hook up. We'll also consider the max charge/engine idling when it's appropriate. I appreciate solar would take away all the worries but I didn't just want to stick a plaster over a potential problem and am keen to learn when I don't understand (which is currently quite a lot!)

 

[CampervanOwner]

We definitely used to get 5 days with the fridge on. We used to lose 10% a day.

We have just done Friday night to Monday evening with the fridge on. They never went below 12.1V. Our batteries are 16 years old. Maybe the fact we have always used our batteries a lot made them last longer.

I honestly think batteries are enormously variable.

Btw to get voltage readings you need not to have anything turned on.

I'm so jealous! 5 days!!!

 

[Stu@rt]

@Stu@rt - you say the blue battery bars on the console are "a bit of a novelty"
@yossarian - you say the bars are "pretty accurate"

Thanks both for your reply, but who's right?!

Apologies, I wasn't trying to confuse. Merely trying to reassure that everything sounded "normal" and in my experience your van looks to behave just like mine and others. It didn't sound to me like you had anything to worry about.

 

[WelshGas]

So helpful, thank you. The explanation about having 75amps of usable power makes complete sense.

Being objective therefore, how is it possible for those without solar to obtain the often-claimed 3+ days' use?

Lastly, you say the control panel can show a misleading 100%. Where would I see this? I'm still trying to work out whether the percentage references are depicted by the blue battery bars.

Thank you

Forgot , you have a T6.1 so different Control Panel.

 

[dspuk]

Thanks for the reply. I feel more reassured knowing 2 days' use is not uncommon off hook up. We'll also consider the max charge/engine idling when it's appropriate. I appreciate solar would take away all the worries but I didn't just want to stick a plaster over a potential problem and am keen to learn when I don't understand (which is currently quite a lot!)

I would not call solar a plaster over a problem. It’s highly likely the reality of how long you can get on battery alone did not meet your expectations, while it meets what it was designed to do. 2-3 days. If you have higher needs than it was designed to do then solar gives you that extra few days to meet your use case.

 

[dspuk]

I'm so jealous! 5 days!!!

Keep in mind this is a T5 and you have a 6.1. You’re comparing Apples to Pears. The 6.1 has a different fridge system and in general is more power hungry.

 

[Lambeth Cali]

You have 2 x 75 amp batteries giving a total of 150 amp hrs.
Good practice for AGM leisure batteries is not to run them below 50% capacity which gives you a total of 75 amp hours usable power.

You stated that the display showed between -1 and -4 amps and the ambient temperature was quite warm.

When the display showed -1amp , probably due to just lights you could have run them for 75 hrs ( 3 days ).

When the display showed -4 amps this was the fridge running. So at that current draw you would have had 20 hrs usage. Fortunately the California compressor fridge runs intermittently to maintain the temperature BUT the warmer the ambient temperature the more often it will run.
In winter the fridge might only run for 10 mins/hr so using 4/6 amps/ hr = 0.7 amps/hr.
So your battery will last a 100 hrs.
In a hot summer the fridge may run for 30 mins/hour = 2 amps/ hr so your battery will only last 35 hrs.

NB: because of the Smart Alternator system the leisure batteries are only charged to 80% actual capacity although the Control Panel shows 100%.
Use the Max Charge button on the dash an hour or two before site arrival and this will ensure the Leisure Batteries are fully charged

The clearest explanation of the batteries I’ve ever read !