John Fair
Member Since: 03 Jan 2008
Location: Horning Norfolk UK
Posts: 178
  
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| How to get the most economical use out of the battery? |
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As above, I flattened the main vehicle battery after four days at billing. The aux battery had more life in it but not enough to jump myself and so I required a jump start. No real problems with how or why I don't think but it did make me wonder about how to maximise the main battery life when camping. Is it best to lock and unlock, unlock and don't relock, unlock and leave the door open(ajar) or any other thoughts?
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 18th Jul 2010 6:57 pm |
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Trackman
Member Since: 16 Apr 2010
Location: Glasgow
Posts: 430
  
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Mine draws power if you leave the doors open. Never leave the key in the ignition as that draws more.
I now lock the car, that way I know everything is asleep.
Ian.
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| 18th Jul 2010 11:07 pm |
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John Fair
Member Since: 03 Jan 2008
Location: Horning Norfolk UK
Posts: 178
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I shall have to have a better look one weekend and see how long it takes to go to sleep. I had been locking and unlocking the car as it was at the back of a trade stand and had my stuff in it but I know this powers the car back up. If you leave the doors ajar then the interior lights go to sleep after a short while so I thought ignoring the security issues it might be better? I shall have to check it over really as it has had one battery under warranty already and it makes me wonder if the alternator is lazy as I did in fact start the car for ten mins each day just to charge it up. As I said the irony is the fridge was running constantly at -5 and that battery was fine but the main was dead. If you look on the hidden screen the battery voltage only ever goes to +13.0 but I'm not sure if that's just a quirk of model years or if that's what they all read at? Or is mine low?
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| 19th Jul 2010 11:20 am |
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JimboD3
Member Since: 23 Mar 2009
Location: Hertfordshire
Posts: 348
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Someone once told me that you needed to take a vehicle for a 15 min drive at about 60mph in order to replace the charge in the battery that one start took out of it !...........not sure if that's true or not ? Jim
Standard TDV6 HSE
Non-standard Td5 110 Hardtop
Club Traxide
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| 19th Jul 2010 2:49 pm |
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Alan G
Member Since: 15 Oct 2008
Location: Lanarkshire
Posts: 1372
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You can disable the Auto on function of the interior lightss by pressing and holding the centre light button at the front interior lamp. It should come up on the LCD display on the dash to confirm and switching back on is the same routine. Check your handbook for instructions under interior lights. ATB
Alan
http://www.youtube.com/user/Bonzo676767#p/u
Last edited by Alan G on 19th Jul 2010 4:55 pm. Edited 1 time in total
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| 19th Jul 2010 3:14 pm |
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adam
Member Since: 20 Sep 2005
Location: Home and Happy
Posts: 6917
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Having left keys in ignition once, I can comment on how remarkably quickly the battery flattens
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| 19th Jul 2010 3:23 pm |
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John Fair
Member Since: 03 Jan 2008
Location: Horning Norfolk UK
Posts: 178
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Oh yes, turning off interior lamps that would help a bit as they take a while to go to sleep. Must remember to try that as I tend to forget all these functions are there! You may well be right about running the car as with the traxide split charge it tries to charge both batteries within about 1 min of start up but I only really want to boost the main. I wonder if I could add in a timer relay to do this in conjunction with the voltage sensor? Would love to know how long it really takes to give a usefull short boost to the main battery? Anyone?
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| 19th Jul 2010 5:41 pm |
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Trackman
Member Since: 16 Apr 2010
Location: Glasgow
Posts: 430
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I would say that running it for 10mins does not put back in what you took out of the battery to start it. I know its not cold just now but they used to say that after starting you need to run for 30mins.
Did a test a few months ago after I started and ran the car for about 7mins, the car had not moved for about 5 days, I put the battery charger on to see the effect. It took an hour to get the battery back up to "normal" and was using a 10amp charger.
Ian
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| 19th Jul 2010 10:41 pm |
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drivesafe
Member Since: 23 Feb 2006
Location: Gold Coast, Australia
Posts: 867
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Hi John, there’s no need to isolate the second battery because the D4 ( and D3 ) produce high enough currents at idle to easily charge both batteries at the same time.
You first and obvious problem as pointed out above, is that you didn’t idle long enough.
But even at 10 minutes, because of the way my isolators work, you would have replaced the equivalent power that a 20 minute idle would replace in a single battery set up.
It’s this last bit that has me curious, my isolator shares the load over both batteries, so while you would be using power either from the fridge or from your D4s electrics, once the common voltage of both batteries got 12.1v, the batteries would isolate, which is sounds like they did.
At this point, you could take your cranking battery down to 11.5v and still start your motor. There must be something pulling a fair bit of power on the D4 side of the isolator for you to not be able to start your motor.
It may well have been as you posted, you were just in and out of your D4 so much that it just pulled a heap of reserve capacity from the cranking battery.
As to the voltage on your screen, someone else can correct this if it’s wrong but I think it only shows in increments of 0.5v and if so, it’s not really that useful for indicating charge voltages.
But even so, while it takes longer to recharge a battery, the lower the voltage is, at 13v 9 and I would be very surprised if it’s not high than that ) you will still charge your batteries.
Plus, even at 13v, if your batteries are low, you will be getting some high currents charging them. 2008 TDV8 RR Lux + 2009 D4 2.7
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| 24th Jul 2010 12:55 am |
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John Fair
Member Since: 03 Jan 2008
Location: Horning Norfolk UK
Posts: 178
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Thanks for the reply. A long time has passed but i have never been convinced of the vehicles charging. Despite various requests to check it it has only now been diagnosed as having an alternator fault as i suspected all along. It just goes to show that it is not always correct to say that D3/4 has a "lazy" charging/battery system and dont get fobbed off with the "you must only be doing short journeys" rubbish. My fuel bills say not!! 
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| 30th Dec 2010 7:24 pm |
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