Protecting your Starter Battery

You better remember it is fitted! If you have a memory like mine, after 10 weeks you will have forgotten you connected something down there. I used a similar approach when I was building out my van and needed a temporary solution to maintain the shagged starter battery. Used to do through a fuse a week as I forgot about it and used/moved van :)
A better option to that is a a 12V to 12V extension lead. One end to living area socket and the other to the cab 12V socket. Available generally on Amazon for under £15.

The 12V to 12V extension lead sounds like a good solution for the technically illiterate like me. I have my leisure battery on a CTEK smart charger via the EHU (yes I have turned the onboard charger off!) So could I just link the habitation 12V socket to the cab 12V socket? If I did would the plugs get hot or are the currents low enough to prevent this? Any recommendations for an appropriate lead available on line?
Thanks
 
The 12V to 12V extension lead sounds like a good solution for the technically illiterate like me. I have my leisure battery on a CTEK smart charger via the EHU (yes I have turned the onboard charger off!) So could I just link the habitation 12V socket to the cab 12V socket? If I did would the plugs get hot or are the currents low enough to prevent this? Any recommendations for an appropriate lead available on line?
Thanks
There is a current limit of course. The typical 12V socket is rated at 120W/10A, but for the purpose of maintaining the battery, it is more like 1A or so draw tops, so pretty insignificant in power terms. You might get more than that initially if the starter has been left to discharge for a while. In that case if you want to go belts and braces, start the engine and run it for 15 mins or so to just boost it before plugging the lead.
As long as the 12V Cab socket stays live without the ignition (which is the case with most vans) then this kind of lead will do the job.

I have bought a few of these leads - https://amzn.to/2V90wyf . They are pretty good I think (but they have doubled in price since I bought them! £15 is at the pricey end). They are fuse protected both ends. Also remember when not in use to remove the plug BOTH ENDS.
 
Thank you all so far. New person, first-ever post, sure I'll get shouted at for length but here goes.
The below is all to do with my fear of connecting a simple trickle charger to the given engine battery terminals under the bonnet (the actual battery is underfloor in the cab).
I have continually fought engine battery drain – I JUST DON'T FLIPPIN' UNDERSTAND IT, AND WHY IT'S HAPPENING.

The dealer I now go to for all things (not the supplying one – terrible) has taken me into the workshop and shown me the meter connected up showing there is no parasitic draw outside normally expected levels. He's now bored with the times he's shown me.

I have (from new in August 2017) a 2017 Elddis Autoquest 185 on a Peugeot 2.0L Euro 6 Boxer chassis cab. With a 100watt dealer fit solar panel connected to a Truma Solar Dual Battery charger (SDC 10/20) which at first fed only the leisure Battery but, because of the following described engine battery drain, in February 2019 I had my dealer connect also to the engine battery. (Once leisure 'full'; 100% of solar to the engine). It has a Sigma alarm and Phantom tracker both after fit at delivery.

The engine battery has always shown a drain that has (when in secure winter storage – no power available) required it to be driven around 40-60 miles for full warm-up every +/- two weeks when it gets to, at worst, 12.2v (60%). I never let it go below. In summer use (I class as April – November) it goes about +/- 3 weeks but usually, that's about fine for been at home, on our drive (power available) and using, rather than at store location.
But now. Enforced shutdown. If I attach this trickle charger what damage is it going to do? Like water flowing will it go to places it shouldn't and blow fuses, damaged components (ECU, etc).

Early this year in the store I tried the 'red button' on the ignition column to disconnect the battery but I couldn't restart, had to use Lithium power pack jump I carry. So that didn't seem to work. Don't really want to try this again on the drive as would lose alarm and tracker.
We might get through without but I doubt it as from going on to drive on Monday 23rd March (showing 12.8v) it is this morning 12.4v (80%) that's 16 (fairly sunny) days.
So that's it; blood pressure up; waiting to flick a switch on a trickle charger. The answer to this might help a great many readers who don't understand what the heck some posts are on about - Should I? Oh, and is this normal drain or is there something wrong with my 'van'?
 
I have a constant drain on my starter battery as and when the vehicle is locked and alarmed, if your garage man showed you that there was no parasitic load when the vehicle was unlocked well then I would suspect this is correct obviously depending on the vehicle electronics and if some power is required to maintain radio settings.
 
Thank you saxonborg. There will be power used (alarm, tracker, ECU and so on) just never thought it would be so much to be draining an engine battery. My new Ford car with all it's electronic gizmoz (?) just starts after 6 weeks been stood in the drive without any solar or any other input.
I would ask members to understand I am a 69 year old, first time motorhome user from 2017, who was a pen pusher all his life and has zero D.I.Y.; practical skills. I switch things on and expect them to operate providing I have followed all procedures in manuals to keep them that way. When something comes along such as a draining battery which I can't a) technically understand - volts, amps and so on mean nothing to me. and b) put pen to paper to solve then I'm jiggered. It just seems so illogical for a 2017 production light commercial vehicle to be like this. Though the manual does say if not using for some time press red ignition lock button.
But what's the worse that could happen if I do nothing. A flat battery. Call for help, have it replaced, start the van. No jigger can steal it from the drive with a flat battery. Or I take courage, have faith, connect the trickle charger and go. If it blows wires the same thing. Call for help, get fixed.
Ah well. Let's see if other readers comment.
Again, thank you (never written on a forum before - neat eh)
 
No reason why fitting a trickle charger will have any negative consequences.
Batteries lose charge even when not connected to anything. If you can leave your van unused for three weeks and then it will start ok, then my guess would be you do not have any more drain on the starter than would be expected and you are worrying unneccessarily.

You say "It just seems so illogical for a 2017 production light commercial vehicle to be like this. Though the manual does say if not using for some time press red ignition lock button." Is it illogical really? These are, as you say, designed as commerical vehicles, and people don't buy commercial vehicles to have them sit around unused for weeks - they are bought to be used by the business on a 5, 6 or even 7 day a week basis. And if not going to be used for a while (maybe the driver is off on holiday for 2 weeks?), hit the big red button. Seems pretty reasonable to me?

I had a 2005 RAV4 from nearly new - I couldn't go 2 weeks unused without the battery being flattened. Toyotas response ... lock it without the alarm being set! very useful. Your Ford lasting 6 weeks and more is good. Then it is a new car and has a new battery. what will it be like when it is 3 years old like your van?
 
Absolutely right wildebus. My error. Is entirely logical. Thank you for the reassurance over trickle charger. Someone with 2324 posts knows loads more than myself on this and probably all other things van oriented, so a big thank you. Am happy now to do probably in a few days at 12.3v
p.s. my motorhome has been brilliant for us. No issues to bother me at all apart from this. Done 20K miles. Had a trip to France this time last year. Sometimes on my own as my wife not as keen as me so happy to be touring alone.
Looking forward to getting out and about again but happy to be obeying rules at home. My daughter putting in a lot of hours and effort at St Thomas's London. A specialist in A&E and trauma. Best to everyone.
So no more from me now unless I'm asked a question.
 
There is a current limit of course. The typical 12V socket is rated at 120W/10A, but for the purpose of maintaining the battery, it is more like 1A or so draw tops, so pretty insignificant in power terms. You might get more than that initially if the starter has been left to discharge for a while. In that case if you want to go belts and braces, start the engine and run it for 15 mins or so to just boost it before plugging the lead.
As long as the 12V Cab socket stays live without the ignition (which is the case with most vans) then this kind of lead will do the job.

I have bought a few of these leads - https://amzn.to/2V90wyf . They are pretty good I think (but they have doubled in price since I bought them! £15 is at the pricey end). They are fuse protected both ends. Also remember when not in use to remove the plug BOTH ENDS.

That's really helpful, wildebus. I'll certainly give it a go. Many thanks for your help.
 
Absolutely right wildebus. My error. Is entirely logical. Thank you for the reassurance over trickle charger. Someone with 2324 posts knows loads more than myself on this and probably all other things van oriented, so a big thank you. Am happy now to do probably in a few days at 12.3v
p.s. my motorhome has been brilliant for us. No issues to bother me at all apart from this. Done 20K miles. Had a trip to France this time last year. Sometimes on my own as my wife not as keen as me so happy to be touring alone.
Looking forward to getting out and about again but happy to be obeying rules at home. My daughter putting in a lot of hours and effort at St Thomas's London. A specialist in A&E and trauma. Best to everyone.
So no more from me now unless I'm asked a question.
No problem and feel free to ask any questions. There are bound to be Forum members who have "been there, done that" :)

And best wishes and lots of thanks to your daughter for all her work at this critical time (y)
 
Absolutely right wildebus. My error. Is entirely logical. Thank you for the reassurance over trickle charger. Someone with 2324 posts knows loads more than myself on this and probably all other things van oriented, so a big thank you. Am happy now to do probably in a few days at 12.3v
p.s. my motorhome has been brilliant for us. No issues to bother me at all apart from this. Done 20K miles. Had a trip to France this time last year. Sometimes on my own as my wife not as keen as me so happy to be touring alone.
Looking forward to getting out and about again but happy to be obeying rules at home. My daughter putting in a lot of hours and effort at St Thomas's London. A specialist in A&E and trauma. Best to everyone.
So no more from me now unless I'm asked a question.
Hi Proverbs and welcome to the forum :)

Please don't stop posting now that you've dipped a toe in the water! I've been a forum member for many years - both here and originally on Wildcamping - but I still don't understand anything more about electrickery than I did when I started! Well, maybe a little but by no means enough to be able to answer questions on it. Some people were born to be teachers and others really love to pass on their knowledge but don't always find the right words... either way, people here will have the answer, so just grit your teeth, ask any question you like and chat away :) Don't forget though, there's more than one way to skin a cat (sorry cats) so not all our experts will necessarily agree on a solution :ROFLMAO: We were all new once but this is a wonderful community, many of whom are now personal friends who have supported me through bereavement and helped me work out a new way to enjoy my life.... oh and seriously put in some hours helping me with my van :giggle:

You and your wife must be very worried about your daughter at the moment but so proud of her too. We are totally in awe of the NHS staff and all the other amazing people who are keeping us afloat and caring for the sick. Please pass on our thanks for the heroic efforts your daughter and her colleagues are putting in on our behalf.
#NHS ❤
 
Oops, sorry for hijacking the thread David :oops:
 
If you have solar but don't have a separate feed for the vehicle battery then you missed a trick as dual PWM controllers are only a few pounds more than single - a battery maintainer is one solution but a lot more expensive than a dual PWM.
If you don't have an MPPT controller then changing out your old controller might be worth considering as a long term harvesting upgrade.
Even if you can get EHU the onboard charger may well overcharge any batteries attached to it as many are quite old fashioned and end up with a constant current rather than turning off and on in response to battery condition. In which case a small smart charger (<£25) will do a much better job.
 
Have fitted this gizmo to a couple of Hymers that I've previously owned...worked ok, and an easy fit.

You still need solar, or ehu...this will charge the LB's then 'bleed' over into the starter battery.


regards
Allen
 
Have fitted this gizmo to a couple of Hymers that I've previously owned...worked ok, and an easy fit.

You still need solar, or ehu...this will charge the LB's then 'bleed' over into the starter battery.


regards
Allen
Yup, that will work.
Your post reminds me that another option I could have mentioned is to use a TEC3M relay. They are usually found in a towing electrics kit for activating the switched 12V for a fridge in a caravan, but can be used for this purpose as well - and are actually half the price of that one in the link above ;)

However ... I will emphasize that none of these alternatives are actually controlled battery maintainers like the Ablemail AMT is for example. They are just ways to connect the batteries together at a certain voltage and that is not the same thing and not as effective for ultimate long life.
 
Ah - the penny has dropped about the 'smartness' of this device.
If you have an expensive single channel solar controller this makes a lot of sense.
My van had LB solar installed when I bought it and I got the dealer to chuck in a cheap dual charger.
I didn't install it straightaway and inevitably I left the van stood for too long and completely flattened the starter battery. Amazingly despite voyage dropping to 3v it did recover and has been no bother since (3 years!).
I recently bought a Votronic MPPT which whilst not smart on the statrer circuit does ensure a full battery - assuming you start with one after parking up.
 
(Almost) all this overlooks the whole point of having two separate battery systems. The idea is that you can use the power of your habitation batteries, safe in the knowledge that if they run flat, you can still start the engine.
If you are not planning to drive anywhere, there is no need for this separation.
If something is maintaining your leisure batteries, such as mains hookup or a solar panel, there is no reason why the engine battery can't benefit too.
Simply connect a wire from the positive terminal of the starter battery to the positive terminal of a habitation battery.
The wire doesn't have to be particularly thick (better if it isn't, in fact) because the current should not be high.
You'd not want to connect them directly if one battery or the other was flat. If so, get them to a similar sort of voltage first. If necessary, run the engine for two minutes to bring up the lower battery voltage (the voltage rises MUCH faster than the state of charge) by equalising the voltages through the split charge relay.
Then you can connect your wire between the positive terminals.
Disconnect the wire before starting the engine, but in the meantime, the batteries can self-isolate together.
 
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All this overlooks the whole point of having two separate battery systems.......
I didn't quote the whole lot as it repeats what has been said, but as you start off with "All this overlooks ..." I thought I would point out that in the original post, and quite a few replies, the method of just connecting the batteries WAS discussed, and at some length.

Thanks anyway for your interest in commenting and reading (some ;) ) of the thread.
 
It was discussed in between, but without the explanation of why or how best to do it.
You have a point. I've amended my comment.
 
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My current favourite combined Mppt & b2b can charge the chassis battery from solar unfortunately it like many of these combo units has very low max voc though of 25v which limits the type of panels that can be used.

 

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