voltmeter bodge job

[Rob101]

Hi All,
My (new with bongo in January) leisure battery is giving me grief. It went flat after an 8 hour coolbox experiment first time we camped, and doesn't seem to have recovered fully since. Now it struggles to power the stereo and internal lights ! All is fine with the engine running, reading > 14V across the terminals, but the stereo is enough to kill it after an hour with the ignition off.. I thought leisure batteries were supposed to survive deep cycles !

To investigate further, I was thinking about bodging up a voltmeter to allow continual monitoring. So todays question to you enlightened folks is : would it be possible to buy one of these digital panels : ebay item 280268820143, and wire it straight to a ciggie lighter plug?? Therefore I could plug it in and watch from the comfort of the cab .

Other (possibly unrelated) symptoms :
The LED on the leisure battery never seemed to work. Supposed to glow green ?
I hear a click when I lift off the accelerator. My theory is that it is the relay switching off, but then shouldn't it be on at tickover??

All theories / answers gratefully received as always

Rob

[Simon Jones]

That would do the job - I've got one & the ammeter version:





Alternatively, get a cheap multimeter for £5 from Maplins & wire a cigarette lighter plug to it so you can connect it that way.

I think the green thing you refer to on the leisure battery is a gauge for the electrolyte level (distilled water) & not an LED. If it starts glowing - run very fast

What sort of split charge system have you got? I'd be surprised if you could hear it click with the engine running, generally the alternator kicks out enough to activate it as soon as its running. Even at idling, the alternator will provide at least 13v.

[mikeonb4c]

I can't top Simons set up but have at least fitted an LED voltmeter after a similar experience like yours with a deeply discharged LB (though it doesn't appear to have suffered from the experience).

[dreamwarrioruk]

very neat looking screens there, ive just got one single colour changing led that tells me all i need to know. green, amber red.

[dandywarhol]

Got one of these on Fleabay for a fiver inc. postage

http://www.lechi.com/discE.htm

[mikeonb4c]

very neat looking screens there, ive just got one single colour changing led that tells me all i need to know. green, amber red.

Its a Thunderbird 2 thing Mike - just love all those dials and readouts

I wish I was kidding - but I'm not. How sad

[Rob101]

Ta for the info all, dammit Simon I've got another dose of Bongo envy - great looking setup !! Does the switch power them off completely, or just control the backlights? I like the idea for the the multimeter option too - I got an extra one BOGOF from Maplins so I'll happily hack the leads to a ciggie plug. This temporary option will suit me as I value my cubbyholes too much !

The LED on my battery says something along the lines of 'Green - OK, White - Needs Charging and Red - Low', but I've never seen it do anything..

Once I get the voltmeter setup, I'll be back with armed with more questions

Cheers

Rob

[Simon Jones]

I wanted to get a proper battery monitoring thing, but in the end couldn't find anything that was quite right or in my price range. This is probably just a temporary thing until I find a better solution. The switch does 3 things: off / on / on with backlight. The meters themselves have the backlight on all the time they are powered, so I added a connection for the switch.

The ammeter is yet to be connected up, but it just needs an in-line 50A shunt to be fitted to the leisure battery. Another job to finish...

[Rob101]

Righty ho - after buying a £1.99 cigarette plug from Maplins and butchering the leads from one of their voltmeters I now have a plug-in battery monitor . I won't post pictures having seen the above offerings !!

So, just returned from trying it and here are the findings :

Plugged it in : 10.0 V
Turned on CD player : dropping dropping to about 9.7V
CD off : back to 10 ish V
Fired up the engine : 10V for about 5-10 seconds then 'click' noise from near the bulkhead and a steady 14.3V.
Let the engine run for about 5 min.. When turned off the voltage slowly dropped down towards 12.5V.
After approx 1 minute with the engine off, i heard the relay click again, with an instant drop again to 10.5V, followed by a slower decline..

Soo - alternator / split charging seems to be working.
Is the consensus my leisure battery is goosed??
Should I buy a mains charger and try topping it up??
Any other tests / guidelines to determine its health??

A long run should put some charge in the battery, but even after 1-2 hours of driving the damn thing doesnt seem to last long at all.. I'm a bit disappointed to tell the truth as it cost nearly £200 to get it all installed at point of sale..

Cheers all,

Rob

[Simon Jones]

I think you should repeat the excercise, but after it has run for a few mins, switch off & disconnect the positive lead from the battery. Then put the other meter across the battery terminals & see if it drops in the same way. If it drops, then goosed battery is likely, but if it retains the charge, then it suggests the problem is a circuit in the van which is draining it. The radio seems to be a common cause of drain even when not switched on.

[francophile1947]

10V = flat battery. Try charging it with a battery charger for 24 hours and see what happens.