Jump to content

EHC charging starter battery


rooster63

Recommended Posts

I have a campervan based on a Citroen Relay and have found that if I don't use it for about 5 days the starter battery doesn't have enough juice to start the engine. I have a CBE PC 200 control panel with a DS-300 distribution box. I have checked the wiring and as far as I can tell all the wiring is in place to charge the starter battery. It is difficult to trace all the wiring from the B1 terminal on the DS 300 but it is the same colour (orange) as a wire that is attached to the starter battery. There are several connections on the starter battery so difficult to determine what goes where! If I run the engine the CBE panel is showing approx 14.2V for both batteries. If engine off approx 12.8 for both again. After 3 days or so it has dropped on the starter to about 12.2. If i connect the EHC the leisure battery shows about 13.2 but no change on the starter. If I check with a voltmeter there is a definite increase with the EHC on the leisure battery but no difference on the starter whether the EHC is on or off. Have checked all the fuses I can find. There seem to be some strange flat ridged fuses on the battery, I assume they are fuses as the are marked 20 or 30 Amps. Any thoughts or do I need to get a vehicle electrician. I'd rather go down the Charging route rather than find out what is draining the battery(probably the alarm) as it is easy enough to keep the EHC plugged in and we only camp off grid for a couple of days or so and therefore the engine soon charges up the batteries.
Link to comment
Share on other sites

How old is the van? It may also be helpful to say what make/model it is. Finally, do you know the age of the starter battery?

 

Even with an alarm, I would expect a fully charged (but is it, as the voltage when the engine is running is the charging voltage from the alternator, not the battery voltage?) starter battery to hold its charge well in excess of 5 days - assuming there is no other, as yet undetected, drain.

 

There could be a blown fuse or a loose connection between the CBE and the starter battery, that is preventing the charge reaching the starter battery. However, not all vans have a facility for starter battery charging.

 

Finally, it may be that the battery is past it's sell by date, which would explain why it isn't holding charge.

Link to comment
Share on other sites

The battery is nearly new and was actually swopped for another new one just in case there was a fault. As far as voltages are concerned when the engine is running I only mentioned that as it shows the battery is charging from the alternator and there are connections to the CBE panel as the voltage on charge and at rest is being detected. The van is a PJB BaCCs 2007, a very rare conversion and as I have found from an earlier post possibly unique so nothing to compare with.

Probably will enlist the services of a vehicle electrician and make sure he knows his stuff, not just wiring for cars, he does do wiring for caravan connections. The Citroen garage did test the discharge flow when engine not running and said there was nothing unusual showing and no reason for the battery losing charge. Shortly after buying the van I did have an after fit Cobra alarm fitted so whether that is the problem I'm not sure.

Link to comment
Share on other sites

Hi Rooster,

 

I am sorry that you have problems, but this is just the sort of thing that interests me, as my PVC has a PC200 system with DS520 distribution board.

 

The CBE mains charging system for the vehicle battery (B1), consists of the charger, a mains charging relay, a blocking diode, and a current limiting positive temperature coefficient (PTC) thermistor. All of the last three components are integral to the distribution board.

 

The mains charging relay is operated electronically by a separate low current signal (S) from the charger. Is it possible that this signal from the charger is missing?

 

As a quick check does the PC200 display show a plug icon when you switch on EHU? It could be that if you have never had this icon displayed, you would not miss it.

 

Please do be aware that the "S" signal is only rated at 50mA.

 

If the mains plug icon does not show on the display when it should, you will need to locate the connection point on the DS320 via the user manual. Check that the connection has been made.

 

A second check is at the charger there should be the mains input (Live, Neutral, and Earth), +ve and -ve output both thick wires, and a third thin wire for the "S" signal. On my CB-516 charger the outpute connections are via a 4 pole connector.

 

IF REMOVING THE CHARGER OR DS320 COVERS, DISCONNECT FROM EHU, AND REMOVE BOTH BATTERY (B1 & B2) FUSES.

 

 

Additional Information.

 

In general the CBE system requires only one connection to vehicle battery (B1). This connection should be fused (50A recommended) close to the battery. On the DS520 connection for 12V power to a 3 way fridge is available from the DS520, not sure about DS320 but probably similar.

 

The CBE system does not use a D+ connection to control power to the fridge, and to couple to B1 & B2, but creates its own simulated D+ by using an ignition switch controlled supply, which is monitored electronically for charging voltage.

 

As regards the displayed voltage for the vehicle battery, this is only taken from the B1 terminal of the distribution board, and could be misleading, but your readings do seem to indicate that you have a connection to B1.

 

Personally I would be concerned about the apparent high drain on you vehicle battery. My vehicle battery is now over 11 years old. One of my checks is to leave the vehicle standing for several days, and then test start the engine. I am considering replacement as a precaution.

 

Alan

 

Link to comment
Share on other sites

When the engine battery is charged fully disconnect the battery lead leave it for a few days before reconnecting it then see if it's able to start van.I believe some EHU chargers don't switch to engine battery until Leasure Battery's are fully charged

 

Link to comment
Share on other sites

witzend - 2017-03-23 3:52 PM

 

When the engine battery is charged fully disconnect the battery lead leave it for a few days before reconnecting it then see if it's able to start van.I believe some EHU chargers don't switch to engine battery until Leasure Battery's are fully charged

 

Rooster has already told us that the battery is nearly new, and has been tested by substitution, so the inability of the starter battery to hold a charge does not seem to be the problem.

 

As regards waiting until the leisure battery is fully charged before charging the vehicle battery, That may be the case for some systems, but having used a CBE PC200 system for over 10 years I have no reason to suspect that the method of operation is any different to that which I described previously. Please do correct me if I am wrong. This is how we learn.

 

I should have pointed out that on the CBE PC200 system the final mains charge voltage at the vehicle battery (B1), will be at least 0.4V lower that that at the leisure battery (B2). This is mostly due to the forward voltage drop in the Schottky blocking diode

 

Further info: It is possible to adjust the PC200 voltage readout should the need arise.

 

Alan

Link to comment
Share on other sites

Operating instructions for a PC-100/PC-200 + DS-300 can be viewed/downloaded via this link

 

http://www.marcleleisure.co.uk/store/pdf/PC100_PC200_DS300_ENcircuits.pdf

 

What OUGHT to happen regarding battery charging is as follows:

 

STARTER-BATTERY (B1) RECHARGING

 

When the battery charger is charging, an electronic device allows recharging (max 2A) of the starter-battery (B1). The system gives priority to the leisure-battery (B2).

 

(My experience is that recharging via the battery-charger is not only limited to a maximum of 2 Amps, but the voltage is also limited. Essentially, the starter-battery is only ’trickle charged’.)

 

LEISURE-BATTERY (B2) RECHARGING

 

a) via the vehicle’s alternator: through a ‘coupler/separator’ relay when the vehicle’s engine is started. The +KEY engine starting controls electronically a small relay which controls other relays: parallel-connection, fridge, awning light, etc.

 

b) via a 230V hook-up using the onboard battery-charger.

 

c) by solar panel: through a solar regulator.

 

ELECTRONIC BATTERY SEPARATOR

 

An electronic device, which is controlled by the +KEY engine starting. It parallel-connects the leisure-battery to the starter-battery when the alternator voltage exceeds 13.3V and disconnects the batteries when the engine starting key is off or the alternator’s voltage is below 12V.

This device also controls also the awning light’s relay so that the light only illuminates when the engine is not running.

 

 

Thr battery-charger that is normally used with a PC-100/PC-200 system is the CB-516 model as shown here

 

http://www.marcleleisure.co.uk/store/electronic-battery-charger-cb516-p-4221.html?osCsid=4c777b0abc95ddf7c1519682d6e0922d

Link to comment
Share on other sites

Rooster, you write, "If I connect the EHC the leisure battery shows about 13.2...."

 

That is very low for a CBE charger, I would expect at least 13.8v? That suggests that either the Leisure batteries are very poor, thereby taking so much current they are dragging down the voltage or the charger is suspect?

 

The Starter battery will ONLY get any charge when the habitation batteries are up to full charge.

If the Hab batteries are poor, the battery bank has been expanded or both, then it is possible they will not reach a sufficient level for the Starter battery to get a 'look-in'.

 

However, regardless of the charge at the Starter battery, it should not drop to the low volts you are seeing in days, it should take weeks?

What you are describing is serious current draw so should be easy to find.

 

Suggest you get an Auto sparky to determine the exact idle draw at the Starter battery and then he is probably the best to determine what is taking it? He will also be able to check out the charger.

 

A lot of them are mobile, are experts at electrics so should find your issue very quickly, thereby not costing big money like you might pay at a dealer?

 

 

 

 

 

 

Link to comment
Share on other sites

Alanb - 2017-03-23 6:22 PM

Rooster has already told us that the battery is nearly new, and has been tested by substitution, so the inability of the starter battery to hold a charge does not seem to be the problem.

 

So doing as I suggest would prove this

 

As regards waiting until the leisure battery is fully charged before charging the vehicle battery, That may be the case for some systems, but having used a CBE PC200 system for over 10 years I have no reason to suspect that the method of operation is any different to that which I described previously. Please do correct me if I am wrong. This is how we learn.

 

Seems like other's have corrected You Alan

 

 

Link to comment
Share on other sites

CBE’s advice is that battery-charging is prioritised towards the leisure-batttery, but it does not say that the leisure-battery needs to be ‘fully charged’ before a charge is passed to the starter-battery.

 

Assuming that the battery-charger in rooster63’s motorhome is a CB-516

 

http://www.cbe.it/sites/default/files/CB510-516.pdf

 

this OUGHT to be able to charge at over 14V initially. That appears not to be happening here - 13.2V was quoted for charging the leisure-battery, with nil charge going to the starter-battery.

 

My Hobby motorhome had the PC-100 version of this system and (as AlanB has mentioned) I always found that, when the battery-charger was charging the leisure-battery, the starter-battery was also receiving charge. However (as aandncaravan has suggested) there may well be a voltage threshold below which charge is not passed to the starter-battery. Both Alanb and I are accustomed to CBE systems that are operating as expected, but if there’s something wrong with the batteries, charger or DS-300 unit of rooster63’s motorhome the effect may be unpredictable.

 

There are basic tests that can be performed, but if rooster63 plans to involve an auto-electrician as he says in his yesterday’s posting, it would be sensible for the electrician to do this.

Link to comment
Share on other sites

  • 2 weeks later...

Haven't got around to getting a sparkie in yet but have discovered that the white S1 cable is not connected and never has been, there is just a clipped off remains disappearing into the sheathing with the 2 DC wires. The original charger supplied with the van had started getting very hot so I replaced it with a Rovert 3 stage leisure battery charger, which only has 2 DC outputs so it looks like charging the leisure battery was never an option. Looks like I will have to get a sparkie in to check the drainage.

Incidently when I switch the CBE on all of the icons flash but then unless I press one of the test buttons to get the temp etc the only display showing is the time. If the engine is running the G icon doesn't light up but I'm pretty sure that the alternator is charging the leisure battery as the voltage measure across the poles of the battery is higher with the engine running.

Link to comment
Share on other sites

rooster63

 

You may wish to consider the purchase of a DC Clamp-On Ammeter. It will probably be a lot cheaper than an auto electrician, and you would have a useful tool at the .of the day. (These instruments usually can do more than just measure current, but do be warned that at low currents the accuracy is generally degraded.)

 

You now know why the mains charger is not charging the starter battery (B1). Also you will not get the mains charger ON (plug) icon.

 

As has been stated previously in information posted by Derek, the mains charging current is limited to about 2A max. Also due to the forward voltage drop in the diode that is in the circuit, B1 charging voltage from mains, will always be about 0.4V lower than B2 which will be close to the charger output voltage. This is how preference is given to B2.

 

The lack of the batteries coupled/generator icon is worrying. It should show when the habitation battery (B2) is receiving charge from the alternator via the connection to B1.

 

In your original post you quoted 14.2V as the on charge voltage. That seems to be OK but it would be reassuring if you where able to read a similar voltage on another vehicle.

 

Is the Ignition +ve (probably a blue wire) connected at the distribution board next to the "S" signal? The batteries are coupled for charging when the voltage at this point is high enough.

 

As B2 appears to getting charged from the alternator is it possible that the normal functioning of the CBE system has been replaced by separate relays, operated from the alternator D+ (CBE systems do not use a D+ connection.) It would need one or two relays to cater for the fridge and charging functions.

 

If you wish to pursue the mains charger function it should be possible to connect the free end of your "S" signal wire to 12V +ve. As we do not know what has happened here, I would test this via a resistor of as a precautionary current limiting device, perhaps 2 x 100 ohms in series, then remove resistance as confidence grows. For physical handling I would suggest 2 off Maplin W100R. When wired in series these would not get too hot even when connected directly across 12V. Any bare wire ends/connections in your test rig should be insulated.

 

With the test above you should get the plug icon showing even without the mains charger on. Do not leave it connected or your habitation battery will discharge into your starter battery.

 

Given a satisfactory function check you could use a suitably adjusted voltage monitoring relay to supply the missing "S" signal, or more simply an illuminated switch.

 

 

 

 

 

 

 

Link to comment
Share on other sites

Since making previous posts on this thread, I have carried out some further investigations on my CBE DS520 distribution board.

 

As a result I now think that I was incorrect in suspecting an electronic driver for the relay that contols the mains charging of the starting battery.

 

The measured current flowing into the "S" input, and the quoted relay resistance, suggest that the relay coil is directly energised from the charger "S" signal output.

 

Of lesser importance, I now think that the blocking diode in the circuit is probably a standard silicon diode rather than a more efficient Schottky diode.

 

This means that the habitation battery will have to be at least 0.6V thah the vehicle battery before the vehicle battery receives any mains charge. It is this voltage difference that gives mains charging priority to the habitation battery.

 

It may be interesting to note that the Schaudt Electroblok circuitry for this function is similar.

 

Alan

Link to comment
Share on other sites

  • 2 weeks later...
Am wondering going down the battery master route to keep the starter battery topped up. As I park my van on the drive with an electrical outlet nearby connecting the EHU is no problem. Any thoughts about the wisdom of that idea. I've got a sparky coming on Friday so will ask him what he thinks but would be good to get 2nd opinion because although he is very experienced and does wiring for towing etc not sure how much he knows about campervan electrics.
Link to comment
Share on other sites

The alternative approach of using a voltage monitoring relay to control the S lead connection would be much less expensive, and would allow some selection of switching voltages.

 

I am not sure of the desireability of leaving the vehicle charger in operation 24/7, as it is not the original CBE 516 device, but it would be possible to follow the route taken by others, and cycle the mains charger/vehicle by using a time switch. I do know that Allan of aandacaravanservices has some opinions about 24/7 charging and battery masters.

 

Allan has a wealth of practical experience on diagnosing and repairing disasters on motorhome 12V electrics.

 

Alan

 

Link to comment
Share on other sites

Had the vehicle electrician around today and he has found there is a 0.5amp drain on the main system. He thinks that it is a fault with the Body Control Unit as he has come across this problem on other 10-12 year old vans. Replacing the BCU is very expensive.

I asked about the possibility of putting a trickle charge (about 1amp) which he suggested wiring into the mains supply and connecting the ends to the B1 and Negative terminal on the distribution board. Not sure if I like the idea of having a charger on all the time I am connected to the EHU.

The other possibility is to buy a Battery Master (Vanbitz) and use the leisure battery to supplement the starter battery. It is no problem to connect the EHU up at home if I'm not using the van for a few days so the leisure battery isn't drained.

At the moment don't do much off grid but wonder how much it would take out of the leisure battery if not connected. The leisure battery is rated at 110 ah so a good size.

 

Any thoughts please?

 

Edit: Changed 110mah to 110 ah (Keithl)

Link to comment
Share on other sites

Rooster,

 

I use a CTEK 5 Amp charger and plug it into the always live cigar lighter socket on the dash when I need to charge the starter battery on our MH.

 

CTEK do a range of 'Comfort' connectors you leave permanently wired in and just plug the charger in when you need to. You can then use the charger for other jobs as well rather than it being permanently wired into one battery.

 

Keith.

Link to comment
Share on other sites

0.5 amp is quite a drain, over 2 days that is 24amps and half of the Starter batteries 'usable' capacity (remember you should not allow a battery to drop below 50% capacity for optimum life).

Although it might be a 100Ah Starter battery, you really only have 50Ah to play with, ideally less.

 

That suggests that in cold weather you might find the vehicle will not starter after just 3 - 4 days when 'off ' the 'home' trickle charger. You might address the loss while outside the house but not in the countryside.

 

That will hit your Free camping quite hard, as not only will the habitation battery need the usual recharging at 3 - days, so will the Starter battery?

 

If you fit a Battery maintainer like the Vanbitz Battery Master it will be taking extra power, just to 'run itself'. It monitors both battery voltages. In order to do this it has to be permanently 'active' drawing power from both the Starter and the Habitation battery, thereby adding to the drain.

 

Additionally when it does kick in it may draw off 20% of the power it transfers. Few battery chargers are 100% efficient, the better ones typically 80%.

 

If you really want to fit a battery maintainer the CBE and Sterling versions are more efficient.

 

 

I think a Battery Master will make things worse. Although the Starter battery will stay charged longer, it is at the expensive of the habitation battery that will drop to needing a charge in about 2 days? If you are frugal.

I think a trickle charger only helps at home, not when being used out and about.

 

Solar would help for 9 months of the year, but throwing away valuable 12amps a day is a waste.

 

What I suggest you look at is targeting the 0.5a drain.

 

How about fitting a battery isolator to the Starter battery, like the one in the photo below, easy to fit if the battery is under the bonnet. Good anti theft device as well.

 

Or :

Why can't the Auto Sparky fit a fuse/switch into the feed for the BCU so you can cut power just to that consumer when the van is idle? Or maybe even the ECU as well to save a few more milliamps?

 

 

 

 

 

773959454_BatteryClamp3.JPG.7b29c388a772a163730f5080b7bdfa66.JPG

Link to comment
Share on other sites

rooster63 - 2017-04-25 11:06 AM

 

Am wondering going down the battery master route to keep the starter battery topped up. As I park my van on the drive with an electrical outlet nearby connecting the EHU is no problem. Any thoughts about the wisdom of that idea. I've got a sparky coming on Friday so will ask him what he thinks but would be good to get 2nd opinion because although he is very experienced and does wiring for towing etc not sure how much he knows about campervan electrics.

 

I have done this for the last 10years over 3 vans, Current van batteries are still the originals & now 5years old. EHU cable left connected all the time & my external socket is switched on/off in the house, so just a question of "flicking" the switch when necessary.

The van does have the ability to charge both starter & leisure batteries, but as the leisure battery only drains whilst the control panel is switched on, almost all the charge is directed to the starter battery.

Link to comment
Share on other sites

  • 2 weeks later...
Getting the 0.5 amp drain fixed looked like it was going to be expensive so have gone down the trickle charger route. Have bought a CTEK charger and permanently attached the connector that has the eyelets to the B1 (starter battery) and earth terminals on the DS 300 distributor box. It is the very easy to connect the charger to the lead and then plug the charger unit into a 240V socket when on EHU. Only need to do this if van not used for 5+ days. Seemed the simplest and cheapest solution.
Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...