CBE CB516 charger working in reverse !!

[BrianK]

Hello All

 

Hopefully someone can help with my problem.

 

I re-did the electrics on my 2014/2015 T5 (including replacing the one habitation battery with two) at the end of last year/start of this and all has been ticking over and playing nicely ever since, some of which is discussed on threads below.

 

https://forums.outandaboutlive.co.uk/forums/Motorhomes/Motorhome-Matters/CBE-CB516-to-CBE-DS300-connection-cable/54102/31/#M637036

 

https://forums.outandaboutlive.co.uk/forums/Motorhomes/Motorhome-Matters/Help-With-Schaudt-WA121545/53448

 

The only thing I have wondered a couple of times is whether the mains charge (CBE CB516) is working correctly, as it seemed to take ages to get anywhere. But I guess because I drive the van quite often and I fitted the, so far excellent Redarc BCDC1240D which seems to charge really well then I hadn’t really thought about it.

 

When I went out to the van today and happened to check the charge on my battery monitor, which has always seemed accurate, I found that since yesterday I have lost about 4.2% somewhere :-( = In spite of being plugged in and not drawing anything!

 

According to the monitor the amperage being drawn is zero so it looks unlikely anything has become faulty and started drawing current even when switched off.

 

The orange ‘ON’ light is on when I plug into the mains. The only other thing of note that might be worth mentioning is that the internal fan in the charger never seems to come on, yet it was nearly always on while the old owners wiring was still in the place, although this was about as thin as spaghetti! However I have never noticed that the charger has even got hot or even warm for that matter.

 

Thanks in advance for any help.

[colin]

The charger is most likely to have packed up, not working in reverse.

[Brian Kirby]

Does your thinking take account of the following - from the CBE 510/516 instruction manual - particularly stage 4?

 

The charging system is carried out in 4 stages:

 

1) Battery charging with maximum current until the end-charge voltage is reached:

Note: the end-charge voltage is reached only if the battery is efficient.

 

2) When the end-charge threshold is reached the charger continues to operate for 90 minutes (lead batteries) or 8 hours (gel batteries) with constant voltage.

 

3) Constant voltage holding 13.8V (gel batteries) or 13.5V (lead batteries).

 

4) After 10 hours, the battery charger reaches the stand-by mode and begins to operate again only when the battery voltage is lower than 13V.

 

In effect, once fully charged the battery is allowed to self-discharge down to 13V before the CBE begins a fresh charge cycle, in preference to running a continual "trickle" at 13.5 V.

 

I have no idea if the above is affected by the presence of the B to B but, as this is intended for alternator charging, I assume not.

[Keithl]

Does your leisure battery voltage rise when you plug in the EHU and switch on the charger?

 

It would be better to check with a voltmeter directly on the battery terminals rather than rely on a built in meter.

 

Keith.

[BrianK]

Thanks all

 

I now feel a bit of a fraud because after my original post I had to go somewhere in the van. After the Redarc had added a little more charge when I arrived home the battery was at about 92.2 %. After being home and plugged into the EHU for half an hour I noticed that the monitor read input charge of 14.6 volts (confirmed with metre on battery terminals) therefore on bulk charge!

 

Surely it can't be the case that after 10 hours it stops charging but simply turning it off for a while and back on again will set it charging again.

 

Brian Kirby - 2020-08-31 2:40 PM

 

Does your thinking take account of the following - from the CBE 510/516 instruction manual - particularly stage 4?

 

The charging system is carried out in 4 stages:

 

1) Battery charging with maximum current until the end-charge voltage is reached:

Note: the end-charge voltage is reached only if the battery is efficient.

 

2) When the end-charge threshold is reached the charger continues to operate for 90 minutes (lead batteries) or 8 hours (gel batteries) with constant voltage.

 

3) Constant voltage holding 13.8V (gel batteries) or 13.5V (lead batteries).

 

4) After 10 hours, the battery charger reaches the stand-by mode and begins to operate again only when the battery voltage is lower than 13V.

 

In effect, once fully charged the battery is allowed to self-discharge down to 13V before the CBE begins a fresh charge cycle, in preference to running a continual "trickle" at 13.5 V.

 

I have no idea if the above is affected by the presence of the B to B but, as this is intended for alternator charging, I assume not.

 

Thanks Brian

 

I agree completely having re-read the documentation, the only thing that doesn't make any sense to me (but may be my being dim) is how the batteries ever become fully charged, which I know they can as they did this when left plugged in continuously at the start of lock-down.

 

FYI my batteries are lead acid and seem to peak at 13.7 volts, which I think is fairly typical from what I've read.

[spirou]

It doesn't specifically say that but it is probably turning off after 10h in float stage rather than 10h since start so by then a battery should be full. Like I said in another thread, % displays are an approximation that depends on many factors that change constantly and can/will go out of sync with time and use.

[Derek Uzzell]

There are two CB516 battery-chargers - the original version (that I assume BrianK has) that was designed to charge wet-acid or gel batteries

 

Link to 12v planet

 

and a more recent model with selectable wet-acid, gel or AGM settings.

 

https://www.cbe.it/newsite/wp-content/uploads/pdfs/000243A_01_CB510_516-3%20con%20cavi.pdf

 

Although the English-language section of the earlier variant’s intruction manual might be considered ambiguous regarding the “after 10 hours” statement, the advice in the other-language sections make the meaning clear. For example, the French-language section says

 

Le système de chargement de la batterie se compose de 4 temps :

1) Recharge de la batterie avec le courant maximal jusqu'à ce qu'elle atteigne la tension de fin de

charge.

NB : La fin de la charge est atteinte seulement si la batterie est performante.

2) Quand le seuil de fin de charge est atteint, la batterie continue à se charger pendant 90 min (batterie

a l' acide) ou pendant 8 heures (batterie au gel) à une tension constante.

3) Maintien de la tension constante de 13,8V (batterie gel) ou 13,5V (batterie acide).

4) Apres 10 heures de maintien de la charge , le chargeur de batterie entre dans une phase de

Stand-By et reprend le charge seulement quand la batterie redescend sous les 13V.

 

Earlier this year, BrianK asked about the fan of a CB516 charger running continuously.

 

https://forums.outandaboutlive.co.uk/forums/Motorhomes/Motorhome-Matters/CBE-CB516-to-CBE-DS300-connection-cable/54102/31/

 

and I’d definitely expect any CB516 device to become at least ‘warm' when it is charging. A truly ‘cold’ CB516 would not be charging.

 

I’m not sure how to interpret BrianK’s comment

 

FYI my batteries are lead acid and seem to peak at 13.7 volts, which I think is fairly typical from what I've read.

 

A fully-charged top quality wet-acid 12-volt battery in first class condition, having been allowed to “rest” for a few hours (or days) with no load being drawn from it (or charge going to it) will balance out its charge and measure about 12.6V to 13V between terminals.

 

http://cdn2.hubspot.net/hubfs/2154717/pdf/faq.pdf

 

A voltage reading of 13.7V indicates either that the battery had been on charge but was not allowed to ‘rest’ sufficiently before the reading was taken, or that it is actually receiving a 13.7V charge.

[BrianK]

Thanks chaps. Better just clear up a couple of mistakes/ommisions I made *-) =

 

I will try to dig out the details of the monitor when I get back tonight (I don’t think I have posted anything here concerning it). My thoughts were that when set-up the way I did this, taking into ci=0nsideration resting and the full AH of the batteries, it should be accurate, at least while the batteries are fairly new.

 

1. My charger must be the second type as I have the A-B-C selector, However I seem to remember setting it at B thinking the longer absorption charge period would be better. Am I wrong?

2. I forgot all about mentioning the fan running all of the time. Rightly or wrongly I put this down to the very thin wiring provided by the last keeping.

3. The charger is under the front of the drivers seat and when I have gone to switch it on and off I really can’t say I have felt any warmth from it (post wiring change).

4.Sorry below statement meant to read peak at 12.7 volts, it seems I got it mixed up with the float stage charging!!

 

FYI my batteries are lead acid and seem to peak at 13.7 volts, which I think is fairly typical from what I've read.

[colin]

BrianK - 2020-09-01 9:44 AM

 

 

 

1. My charger must be the second type as I have the A-B-C selector, However I seem to remember setting it at B thinking the longer absorption charge period would be better. Am I wrong?

 

The instructions quite clearly tell you what setting to use depending on type of battery, I would hope the designers know what the best setting is, which in your case would be 'A'.

[BrianK]

I know I'm naughty (lol) =

 

From memory I think I ended up on 'B' having found that "A".seemed to do even less. Plus the fact that my batteries (Bosch 90AH Powerframe L5013) are recommended at a maximum charge rate of up to 14.4 volts.

 

Attached are the details of the monitor I installed. Having followed the fitting instructions I assume that I 'can' rely on using the % scale at least while my batteries are good and new and fresh?

 

The fact that the absorption only lasts for 1.5 hours when switched to 'A' seems a minus to me but hopefully those that understand this charger 99% more than I do will give an opinion.

 

 

[Alanb]

BrianK - 2020-09-01 9:44 AM

 

==================================================================================

3. The charger is under the front of the drivers seat and when I have gone to switch it on and off I really can’t say I have felt any warmth from it (post wiring change).

 

=================================================================================

 

The batteries in my PVC are permanently float charged, by the earlier version of the CB516 charger.

When touched with the palm of my hand, the charger case is only just perceptably above ambient temperature.

I should add that I have moved the charger from the back of the wardrobe to, a better ventilated position behind the driver's seat.

 

Alan

[BrianK]

Tried to add this to the post above but ran out of time!.

 

Given up trying to upload the PDF, even tried breaking into picture files but still gots errors galore! I=The monitor is a Elite DCM120100C

 

https://www.hisse-et-oh.com/system/assets/000/093/889/original/ELITE_-_Amp-Volt-Ah_metre.pdf?1411106362

 

https://masakmasakcaravan.blogspot.com/2018/02/dcm-120100c-voltamp-meter-for-solar.html

[BrianK]

Alanb - 2020-09-02 2:03 PM

BrianK - 2020-09-01 9:44 AM

==================================================================================

3. The charger is under the front of the drivers seat and when I have gone to switch it on and off I really can’t say I have felt any warmth from it (post wiring change).

=================================================================================

The batteries in my PVC are permanently float charged, by the earlier version of the CB516 charger.

When touched with the palm of my hand, the charger case is only just perceptably above ambient temperature.

I should add that I have moved the charger from the back of the wardrobe to, a better ventilated position behind the driver's seat.

Alan

Thanks for the input Alan, mine was in the same position as yours but being a little camper van and also having the distribution board and mains consumer unit in the same area it was a bit squeezed in, hence the re-positioning to under the seat where it gets air from the front, top and both sides.

[spirou]

BrianK - 2020-09-02 2:38 PM

 

Attached are the details of the monitor I installed. Having followed the fitting instructions I assume that I 'can' rely on using the % scale at least while my batteries are good and new and fresh?

 

 

Battery monitors are fairly accurate on voltage/current measurements, everything else is just a calculation. Some are straightforward conversions (W, Ah...) while others are estimates based on assumptions. SOC reading usually takes into account peukert exponent and charge efficiency which are both often approximations to begin with and will depend on other factors (battery chemistry, design, condition, temperature etc.). A 10% margin of error would not be out of place in my experience, sometimes quite a bit more. I usually ignore it altogether.

[BrianK]

Hello everyone

 

To re-visit this if I may. Having been away and now coming back to plugging into the EHU I'm still pretty convinced this charger can't be working correctly still.

 

As previously mentioned I have 2 x Bosch 90AH Powerframe L5013 batteries.

 

Does anyone have a gut feeling rough figure for how long the CB516 should take to fully charge these?

 

Thanks

Brian

[spirou]

Give it a full day

[Derek Uzzell]

BrianK - 2020-10-06 12:18 AM

 

...Does anyone have a gut feeling rough figure for how long the CB516 should take to fully charge these?

 

Thanks

Brian

 

That’s very much a “How long is a piece of string?” question.

 

From what you’ve said earlier your CBE516 charger is the latest type

 

https://www.cbe.it/newsite/wp-content/uploads/pdfs/000243A_01_CB510_516-3%20con%20cavi.pdf

 

It has a 3-position (A, B or C) Charging Line Selector switch

 

A - Conventional wet-acid batteries (which your Bosch L5013 batteries are).

B - Gel batteries.

C - AGM batteries.

 

and the charging regimens are shown in the drawings attached below.

 

Your motorhome has a leisure-battery maximum capacity of 180Ah (2 x 90Ah) and your CB516 charger has a maximum output current of 16A. So - in principle - if both your batteries were 100% ‘empty’ and your charger outputted 16A continuously, the batteries would become fully charged after 11.25 hours. But I’m sure you won’t be discharging your batteries completely, so that figure is just theoretical. As Spirou says, if you allow charging for 24 hours your batteries SHOULD reach full charge if the charger is operating properly.

 

I’ve added to your earlier posting of 2 September 2020 2:16 PM a couple of links relevant to the Elite DCM120100C, but if you want to check the operation of the CB516 charger I suggest you ignore the battery-monitor and take voltage readings regularly at the batteries’ terminals while the CB516 is charging to check whether or not what it’s doing matches what the CB516 charger instructions say it is supposed to do.

 

[Robinhood]

BrianK - 2020-08-31 11:13 PM

 

Surely it can't be the case that after 10 hours it stops charging but simply turning it off for a while and back on again will set it charging again.

 

 

This may be a red herring, but I had an issue from scratch on my 2006 Rapido equipped with a CBE 516 charger.

 

It would work quite happily on the first cycle of charge after being switched on/plugged in, but, once the cycle was complete and the charge dropped to zero the charger would never cut in again, even when the battery voltage had dropped below the required threshold. It had to be turned off and on (or unplugged/replugged) in order to restart charge (and after a full cycle, the same thing happened).

 

It was replaced under warranty.

 

It is fairly unlikely this is at the heart of your problems, but it is relatively easy to check.

 

 

[BrianK]

Thanks everyone for the input

 

Part of my problem has been continuous recent use of the van making it difficult to know when to measure.

 

It has been plugged in and (apparently) charging now for around about 48 hrs.

 

I'm literally about to go away in it for a few days at lunchtime, but to a relatives house so the van won't be used from the leisure point of view.

 

So would it be a good idea when I unplug it to remove the fuse that feeds the Redarc from the vehicle battery so as to rest the leisure batteries? And if so at which point would I expect to get an accurate (rested) reading from them with a multi metre?

 

 

[mikefitz]

Hi BrianK,

 

I have read the posts with interest and have the following comments.

 

The battery monitor you have, whilst perhaps able to measure power in and out of the battery, it cannot, as far as I can see from the instructions, compensate for the fact that with lead acid batteries there is a loss of charge efficiency. Whilst the efficiency is excellent during the bulk stage, when the charge process enters the absorption stage the efficiency drops. The net result is that it takes more power in, to fully charge the battery, than the power that is taken out. Typically it will need at least 10% more.

A further point regarding the monitor is that I doubt it very accurate an low current values. As pointed out by others, (Spirou), battery monitors are a guide only. Even some of the best designed, like the Victron BMV series, are prone to accumulation errors, and need careful setting up to give acceptable results.

 

Regarding the 4% loss you reported, I think this is a separate issue to battery charging or monitor inaccuracy, and indicates something in the van was drawing power. This could be the battery chargers or something else in the van being active, testing all circuits with current monitoring may determine the cause.

 

Your lead acid batteries need a bulk target and absorption voltage of 14.4, with a float of around 13.6. (temperature compensated). Most chargers like the CBE unit dont really know when the battery is full and use an absorption time that's typical for the type of battery in use.

The actual absorption time needed is variable depending on battery type, capacity and depth of discharge when the charging process started. Since most chargers terminate the absorption process before the battery is completely charged, a high float voltage is used to slowly bring the battery to full charge. ( this is not always successful and most battery loss of useful life is the result of being under charged).

Its becoming more common in charger design to adopt a low float voltage, after a period on the higher setting, or to stop charging altogether as the CBE unit does. Having the battery ( with no loads) on high float continuously is a cause of battery damage and thus a reduction is useful life.

With sealed lead acid batteries you can determine full charge when the current is less than 1A ( ideally 0.5A) into the battery per 100Ah of battery under a charge voltage ( 14.4v).

For the LFD90, similar to your batteries, a fully charged rested battery off load should read around 13v.

 

The battery to battery charger fitted, Redarc BCDC1240 may be a little more powerful than needed for two 90A batteries. At a 40 A capability and a 14.6 charge voltage, the batteries, when well discharged, may take in more current than the recommended 10% capacity, say 10 amps for each battery. I note from the specification that it terminates absorption stage when the current falls to less than 4A, the batteries will not be fully charged at this current level. ( this seems a strange process for a unit that also acts as a solar charger). This suggests the charger is more suited to a large 400Ah battery pack. Checking the battery temperature whilst under B to B charge could be useful.

 

Mike

 

[Derek Uzzell]

Brian’s earlier postings provide details of the equipment he has installed

 

https://forums.outandaboutlive.co.uk/forums/search/query.asp?action=search&searchforumid=all&keywords=&author=briank&days=&Submit=Search

 

The control-panel Brian has fitted is a CBE PC210

 

https://magnummotorhomes.co.uk/wp-content/uploads/2018/01/CBE-PC210-Install.pdf

 

and ( I would have thought) in order to confirm initially whether or not the CB516 charger is operating as one might expect, it would just be a matter of hooking up the camper to a 230V power-supply and looking at the control-panel.

 

My Hobby motorhome had a PC100 panel and my Rapido has a PC180 panel. In both cases it was immediately obvious when the motorhome was connected to a 230V EHU that the leisure battery was receiving charge. The PC100 and PC180 panels use LEDs to indicate the voltage of the leisure battery, but the PC210 has a numeric readout that shoild be even more informative.

 

For what it’s worth, this 2018 VW T6 forum thread referred to fitting a CBE kit with a PC210 control-panel and the vehicle being discussed also had a Redarc B2B charger.

 

https://www.t6forum.com/threads/cbe-pc210-power-management.8153/

[BrianK]

Hello again everybody

 

I was away for longer than expected at a relatives but this enabled me to collect the information below.

 

Tuesday 6th Oct

12.30pm - Unplugged from EHU & fuse removed to stop leisure batteries from charging by Redarc

 

11th Oct

?1.52pm (After standing for 48 hours)

12.8 Volts on Monitors

12.55 Volts Multi metre

 

1.55pm Reconnected Redarc charger

3.50pm Left for home (3 Hours journey)

 

6.38pm

13.25 Volts on Monitors

12.55 - 12.95 Volts Multi metre

 

11.05pm

13.18 Volts on Monitors

12.42 Volts Multi metre

 

12th Oct

11.54am

13.07 Volts on Monitors

 

11.54am

13.05 Volts on Monitors

12.72 Multi metre

 

6,45pm

13.07 Volts on Monitors

12.65 Multi metre

 

11.20pm

13.02 Volts on Monitors

12.62 Multi metre

 

Is this behaviour from my batteries reasonable?

 

What I do understand

The batteries take a while to rest and the initial voltage is unrealistically high

 

What I don't understand

Do we assume my multi metre is the correct reading? (picture attached)

Is there a recommended set rest period?

When plugging the vehicle in or driving now and then how can you hope to know the voltage if they always sits unrealistically high?

I don’t get how I followed the info on the video below but my percentage on the DCM120100C monitor is way out, showing about 10%!

[Derek Uzzell]

Your leisure batteries are Bosch L5013 - the same dual-purpose wet-acid battery as a Varta LFD90.

 

The percentage State of Charge (SoC) of an ordinary wet-acid battery is shown in the table attached below.

 

This assumes that the battery has ‘rested’ for a sufficient period of time (this link suggests not receiving any charge for 12-24 hours)

 

https://www.batterystuff.com/kb/frequently-asked-questions/powersports-batteries-faq/12-volt-battery-reading-13-volts.html

 

that the readings are taken at the battery’s terminals with an accurate voltmeter, and that there is absolutely no load being placed on the battery that might distort the readings. The last requirement may not be easy to meet while the battery is in situ (particularly with starter batteries) as maintaining any dashboard or control-panel stored data can lower the SoC reading a surprising amount.

 

What this boils down to in your case is that, if your wet-acid leisure batteries have been fully charged (by the CBE516 charger or the Redarc device), there’s zero load on the batteries and they’ve been allowed to rest for (say) 12 hours and your multimeter reads voltage accurately, a 12.7 voltage reading should be about as high as one can expect.

[BrianK]

Derek,

 

Many thanks for the help

 

I’m surprised at the table you included having always thought the absolute minimum these batteries should be run down to was 50% , whereas I presume this chart gives the impression I can safely go down to 40% charge? Can you confirm this is definitely correct in my case?

 

In my installation I never made the connection back to the van battery only the leisure ones so if I press the button ’twice’ on the PC210 for ‘vehicle’ battery I just get 00.00

 

So it seems to me that it’s starting to look like my CB516 may well work OK and it was me that was faulty.

 

The van is at home for a short time now so I plugged It back into the UHU for 24 hours or so, and unplugged it again this morning to reset it for further measurements.

 

colin - 2020-09-01 10:47 AM

BrianK - 2020-09-01 9:44 AM

1. My charger must be the second type as I have the A-B-C selector, However I seem to remember setting it at B thinking the longer absorption charge period would be better. Am I wrong?

The instructions quite clearly tell you what setting to use depending on type of battery, I would hope the designers know what the best setting is, which in your case would be 'A'.

This is probably a good to time to mention that when I checked the selector switch not only was it to the left, so switched to position A'' but the switch didn’t seem to want to be placed in position ‘B' at all. To reiterate what I mean it is as if there is only 2 positions not 3, not sure if anyone else has experienced this, yet it definitely does seem to be the ‘later’ model which should have these 3 choices of position.

 

Conclusions

That the DCM120100C is useless if you want to read your available 'battery left' as a percentage

That the DCM120100C voltage reading isn’t adjustable?!

 

Things that still confuse me

I can’t for the life of me work out how/why the voltage read from a multi metre is much more accurate than BOTH of the monitors

When using the van on a daily basis, in my case used for fishing trips where I often move the van either morning (4 to 6am) or/and evening (6 to 10pm) to change venues. How will I ever be able to rely on any measurement if I’m continuously drawing power for the fridge (important for bait) or heating at this time of year and also of course often starting the engine, and therefore the Redarc B2B charger, as well?

 

Fully prepared and more than happy to be educated by those who know far more than I do.

[Derek Uzzell]

BrianK - 2020-10-14 7:03 PM

 

I’m surprised at the table you included having always thought the absolute minimum these batteries should be run down to was 50% , whereas I presume this chart gives the impression I can safely go down to 40% charge? Can you confirm this is definitely correct in my case?

 

 

I take no resposibility for how you have interpreted the table I provided. It’s just one of many on the internet and its provision was to indicate that the 100% (full charge) voltage should be expected to be not much higher than 12.7V.

 

There’s a wealth of battery-related advice on the A and N Caravan Services website

 

http://www.aandncaravanservices.co.uk/

 

and you’ll note that the table in the following section differs significantly from the one I provided regarding the percentage state of charge (SoC).

 

http://www.aandncaravanservices.co.uk/battery-technology.php

 

Received wisdom is that discharging a wet-acid battery below a 50% SoC will shorten its useful life.

 

When it comes to your CB516 battery charger, you’ve either got the version with the 2-position battery-type selector switch or the version with the 3-position switch.

 

The former switch is clearly marked “PB” (ordinary wet-acid batteries) or “GEL” (gel batteries) and you should select the “PB” switch position.

 

The 3 postions of the latter charger’s switch are referred to as

 

“A” for lead-acid batteries

“B” for lead-gel batteries

“C” for AGM batteries.

 

I’ve attached an image of the 3-position switch taken from the CBE documnt, but it’s not clear from this how that switch is marked (A, B and C, something else like PB, AGM, GEL, or no marking) - but either way, it’s the “A” or “PB” or leftmost switch position that should be chosen for charging your Bosch batteries.

 

Realistically you shouldn’t expect a device like the Elite monitor that can be bought for a pittance to provide laboratory-standard accuracy. And the only way to be sure of a multimeter’s accuracy will be to compare its readouts with a ‘reference’ meter that’s been tested and its accuracy confirmed.

 

I don’t think you’ll be able to easily obtain the information you want about how much ‘capacity’ remains in your batteries given how you’ll be using your camper for fishing trips - you’ll just have to rely on gut feeling and experience of using the camper and err on the careful side.