New mains charger problems

[Hubble]

Hi
I bought a 2003 westfalia california pop top about 3 weeks ago and soon discovered the mains charger was fried. I got a replacement multi stage charger from Caravan & Leisure Technology (caravantechnology.com) fitted by a local auto electrician.
Before the charger was fitted the control panel was showing the leisure battery at 70% charged (from driving around). The charger was fitted and the electrician tested the voltage when hooked up - 14.6v or something like that. There is an external control/display now mounted inside the cupboard.
With the van on hook up at home the charger display is showing that the battery is now full but curiously the overhead display in the cab is only showing 70%.
I phoned the electrician and was told
a) gel specific chargers only charge to 70-80% of the capacity that chargers designed for lead-acid do.
b) in order to allow for surges created by regenerative braking modern batteries are generally kept at less than maximum charge to allow some headroom.
There may be some truth to explanation a), but regenerative braking in a vehicle with a leisure battery? Sounds unlikely.
Anyway, has anyone had similar experience with a replacement charger?

 

[2into1]

I think his explanation is a load of gobbledygook. I was about to point to a leisure battery needing replacement but have got sidetracked thinking that my display only just shows bars rather than %.
I take more notice of the voltage shown, rather than how many bars I've still got. Does yours quote a % or are you reading that that you've got 8 out of 11 bars (or similar) and therefore calling that 70%?

 

[Hubble]

I'm talking about bars. I thought there 10 bars so I figured 7/10 = 70%. Anyway, it's showing 7 bars. The leisure battery is only 16 months old according to previous owner. It still could be shot though - possibly misused? Shows around 14.5v when driving and 12.5v with engine off. That's without hook up of course.

 

[TwentyOneThirtyFive]

If I remember correctly, the main difference between how different types of batteries are charged is the voltage (and we are only talking and .1 or .2v differences).

Your numbers seem a little different. I see 14.2 max when driving, or when fully charged on hookup. This drops to 13.something and all the bars (or the one fat bar) if the batteries are fully charged. My batteries are coming up to 4 years old. Like peter I consider the voltage more important that the bars.

You won't get a full charge off of the split charge system, so testing should be done on a hookup.

Dropping to 12.5v would indicate that the batteries are not charged, or are not accepting a charge. How long have you left it charging on hookup?

 

[Hubble]

OK thanks I'll double check this and get some definitive readings asap. I had it on hook up for 3 or 4 hours.

 

[TwentyOneThirtyFive]

Leave it hooked up for a couple of days and see what happens.

Not sure what capacity battery is in the late models (120ah?), or the output from the charger (ie. is it 15amp? so 3 or 4 hours is max 60ah in a perfect, lossless world).

 

[2into1]

Do we know what the bars are measuring, other than being a graphical representation of the difference between (say) 12.8v fully charged and 11.2v empty?

BTW, I can't ever remember having a full set of bars. I'm always a few short, even after a new battery.

 

[TwentyOneThirtyFive]

A google translation of the manual says:

9. Capacity of auxiliary batteries
The available battery capacity
is displayed in 10% increments. The display
appears with battery operation for the first time about 5
Minutes after a consumer.
Previously, only the first and last bar symbol
displayed.

Which isn't very helpful... How can it be done on anything other than voltage?

 

[TwentyOneThirtyFive]

Although, the DIP switches are used to configure 1 or 2 batteries and also Sonnenschein or Deta.

I don't know what Deta is, but Exide have a Deta battery that looks to be a more normal cranking battery?

But maybe it is doing something a bit more intelligent? Or maybe it is just that the discharge patterns are different. ie. 12.5v on a gel is half charged, but 12.5 on a wet is three quarters charged?

 

[welshwestie]

Sonnenschein is the GEL charge cycle, and Deta the wet acid setting.

Multistage charge profiles will damage most GEL batteries as they will never be fully charged.

What you need to do is firstly find what battery you have in your wardrobe. Easy to get at. Then with the info get the pdf for that battery so you know the charge profile required for the battery. If your charger is able to provide that charge profile, then you're good to go. If it's not able to as your battery is a GEL and the charger has no GEL profile then at best it will permanently damage the battery, at worse the battery will pop, either slowly, or very quickly with a loud bang. The sooner you check it out the better.

 

[2into1]

Dan, do we get to the dip switches by removing the control panel? (Which from an earlier post isn't that easy if you haven't go the knack)

 

[TwentyOneThirtyFive]

Yes, DIP switches are on the back. Full details in this (German language) manual.

http://www.westfaliat4.info/WestfaliaT4CentralElectronicUnit.pdf

There are also manuals for the original charger at the same location.

 

[sidepod]

Out of interest, how much did your new charger cost including install ?

Pod.

 

[Hubble]

I'll also take a look at the battery at the weekend. I can tell you it's definitely a 140Ah gel battery and the charger has a specific gel battery setting.
It cost me £180 plus VAT plus £60 labour. (plus another £60 for diagnosing the problem in the first place).
Place called Autoleck in Eltham, SE London.

 

[welshwestie]

Okay, look at the charger and see if the charging profile matches your battery. What happens is that chargers can go into float too early for GEL batteries and they never get fully charged.

When on hookup or driving, the central control unit will read 14+volts, this is what most gel batteries need,such as the exide range.

 

[Hubble]

OK so the battery is branded MONBAT and has written on it various things;
GEM automotive batteries
AGM technology
640 901 095 (product code?)
CCA 950 EN
G-627 AGM (BAT 026)
I've mailed MONBAT in Bulgaria to get some technical info on the battery.
I think this is a AGM type battery which is similar but not exactly the same as a Gel cell.

The technical guy at the company that makes the charger tells me that the charger is good for either type.

On sunday morning the van was showing 12.5v on the cab display. I double checked this on the battery with a multi meter and this was correct. I then hooked it up and the charger immediately went into charge mode with the charger display showing 14+ volts and charging at 1 amp (i think) but this only lasted for a few seconds as the charger voltage dropped and the display switched to 'Full' and showed a voltage of 12.9v dropping to 12.8.
The cab display then showed 12.7v, confirmed with the multimeter on the battery.
This morning the cab display was back to 12.5v.
I related all this to the technical guy and thinks it all sounds fine and the charger is working as it should.
Can i accept this?
I think next I'll run the battery right down and recharge from hook up and see how it behaves.

 

[sidepod]

Can I politely ask why you didn't just go for the genuine replacement/Exide(previously Sonnenchein) charger battery combo? Price difference isn't too much from what you paid.

Pod.

 

[Hubble]

The battery was already in the van when I bought it about 4 weeks ago. The original charger that was in the van was burned out. A replacement westfalia charger would be 600 euro (if you could find one in stock) and I have been told, aren't very good anyway. The replacement multistage charger was recommended by the auto electrician.
Obviously, If the charger/battery combination I've now got will work fine I'll stick with it. If not I'll have to replace something.

 

[TwentyOneThirtyFive]

On sunday morning the van was showing 12.5v on the cab display. I double checked this on the battery with a multi meter and this was correct. I then hooked it up and the charger immediately went into charge mode with the charger display showing 14+ volts and charging at 1 amp (i think) but this only lasted for a few seconds as the charger voltage dropped and the display switched to 'Full' and showed a voltage of 12.9v dropping to 12.8.

Doesn't sound right. At 12.5v I would expect the charger to charge at a higher rate.

Assuming 12.5v is battery at half capactiy, It would take 70 hours to recharge at 1amp (battery being 140ah). I would expect higher.

The cab display then showed 12.7v, confirmed with the multimeter on the battery.
This morning the cab display was back to 12.5v.
I related all this to the technical guy and thinks it all sounds fine and the charger is working as it should.
Can i accept this?
I think next I'll run the battery right down and recharge from hook up and see how it behaves.

As a comparison - my van is on hookup permanently when it is outside my house, so I know it's charged before I leave home. On Friday it was showing 14.2v on hookup which included the fridge running. I unplugged it and it dropped to 13.something v. I drove 100 miles, it showing 14.1v all the way. I parked in a field (mostly full of landrovers, but that isn't important!), with the fridge running (6c), lights on during most of the evening. No hookup, no running the engine, no solar, all on battery.

Fridge ran all day Saturday and Sunday, lights on Saturday night. My readout was floating between 12.6v and 12.9v at the end of Sunday (as the fridge does it's stuff).

I have a little more capacity (2x80ah batteries), but even so, you can see that I have a higher voltage after 2 days in a field, using the van, on batteries that are coming up to 4 years old.

edit: charged the phones too!

hth,
dan

 

[TwentyOneThirtyFive]

A replacement westfalia charger would be 600 euro (if you could find one in stock) and I have been told, aren't very good anyway. The replacement multistage charger was recommended by the auto electrician.
Obviously, If the charger/battery combination I've now got will work fine I'll stick with it. If not I'll have to replace something.

If you do eventually find you need to replace the new charger, there is a modern direct replacement available at less cost. Info in the useful info thread.

http://vwcaliforniaclub.com/threads/t4-westfalia-useful-information.5207/page-2#post-104925

 

[sidepod]

Doesn't sound right. At 12.5v I would expect the charger to charge at a higher rate.

Assuming 12.5v is battery at half capactiy, It would take 70 hours to recharge at 1amp (battery being 140ah). I would expect higher.



As a comparison - my van is on hookup permanently when it is outside my house, so I know it's charged before I leave home. On Friday it was showing 14.2v on hookup which included the fridge running. I unplugged it and it dropped to 13.something v. I drove 100 miles, it showing 14.1v all the way. I parked in a field (mostly full of landrovers, but that isn't important!), with the fridge running (6c), lights on during most of the evening. No hookup, no running the engine, no solar, all on battery.

Fridge ran all day Saturday and Sunday, lights on Saturday night. My readout was floating between 12.6v and 12.9v at the end of Sunday (as the fridge does it's stuff).

I have a little more capacity (2x80ah batteries), but even so, you can see that I have a higher voltage after 2 days in a field, using the van, on batteries that are coming up to 4 years old.

edit: charged the phones too!

hth,
dan

Sounds spot on to me. Are the origninal units no longer avail from Gunz?

 

[TwentyOneThirtyFive]

The original units are still available from Guenzl. They are 599 euros.

As an aside, just looked at the original charger docs and they charged at max 9 amps, the later replacements from Guenzl at max 12 amps. I don't see what the trickle charge current is.

The Farron unit is max 20amps.

 

[welshwestie]

I think your battery is the mobat AGM HD according to the info you provided.

Whilst I couldn't find a data sheet for the HD, I did find one for another Monbat AGM. Recommended charge is 14.4v with a float of 13.6 v.
If your battery has the same profile, then I would say two things, the battery is not being fully charged, as it's switching to float too soon, and then the second problem, your float charge is too low. I would wait for monbat to get back to you as they will give you the information you require, if I was a betting person, I think I am not too far off what's going on. However, I could be wrong.

 

[Hubble]

I think your battery is the mobat AGM HD according to the info you provided.

Whilst I couldn't find a data sheet for the HD, I did find one for another Monbat AGM. Recommended charge is 14.4v with a float of 13.6 v.
If your battery has the same profile, then I would say two things, the battery is not being fully charged, as it's switching to float too soon, and then the second problem, your float charge is too low. I would wait for monbat to get back to you as they will give you the information you require, if I was a betting person, I think I am not too far off what's going on. However, I could be wrong.

Thanks Welshwestie
I still haven't heard back from Monbat.
I've uploaded the specs for the charger. I'm still learning about how chargers work but I think you're right. This charger is supposed to float at 13.5v but the one I've got is supplying a float charge of 12.8 or 12.9.
Regardless of whether this charger is a good match for the battery, it's not doing what it's supposed to do. Would you agree?
Thanks again for your help.

 

[2into1]

Can I slightly hi-jack this thread and see if I can understand what triggers the 'plug' symbol to be displayed on the LCD? Is it simply sensing the higher voltage (14ish) from the charger? If so, why doesn't it show with just the charge from the alternator when the engine runs?
Are you getting the 'plug' symbol with the replacement charger?
I'm asking because I've yet to get to understand why my plug symbol comes and goes every 5 seconds when on hook up SINCE I had my solar panel fitted (and the sun is out.....In the dark there is no problem).
I'm worried my charger (from the mains) is switching on and off every few seconds and will burn out.