Jaws
LIFE MEMBER
- Sep 26, 2008
- 23,836
- 72,493
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- MH
- C class, Chieftain
- Exp
- since 2006 ( I think ! )
First off this is not about ANY other model than a 2007 Chieftain SE as I have no way to know what wiring was used on any other van.. Logic suggests all of that era will be the same but I must keep my comments to that of which I absolutely know.
I fitted 300w of solar panel on the roof when we got the van, and used a fairly up market controller with digital display.
From day one there was a discrepancy between the voltages displayed on the solar controller and the vans control unit.. I put that down to a not very accurate read out on one or other of the displays.
Whilst doing the fitting I noticed the feed wires from the Sargent charger to the battery(s) had gone hard and crispy towards the lower ends indicating how hot they had become at times
I just cut them back to good clean wire and refitted*
At the Thetford meet this year I bought a very nice battery condition display unit from John ( @Don Quixote ) and that showed again a discrepancy between the solar controller and the actual battery voltages.
I decided to run a couple of checks and discovered there was indeed a .3 volt** different when the charge or draw was at about 5 amps.
Given the only thing between the two check points was about 3 metres of wire I was quite concerned.. Initially I thought maybe I had made a mistake and connected the solar controller output to the wrong wires.. That was soon dismissed though
Yesterday I doubled up the size of the originally fitted wires from the Sargent unit to the batteries ( To which I had connected the solar feed in )
The difference in voltage read out immediately became 'acceptable' at .01 volts when 5 amps were drawn
Conclusions:
1) * Inspection of the original feed wires from the Sargent charger to the battery(s) should have raised my suspicions from the go that the wiring was not 'man' enough for the job,, but in my defense they appeared to be the correct gauge, were original fit, and I just thought that someone at some time had done something daft with an after market charger and cooked the wires a bit
2) Those wires had got hot. Heat is bloody dangerous !
3) This is the bit that really gets me..
Apart from the obvious danger of wires getting hot there is also the issue that any type of charging system ( mains, engine or solar ) was being fooled in to thinking the batteries were reaching a higher state of charge than was the case.. So what ?
Well the charger ( what ever source ) will shut down and reduce the amperage fed to the batteries if said source believes the charge state is good.
For the past two plus years the solar ( and other ) system has never fully charged the battery(s) as it THOUGHT a fully charged state had been reached
** At a 10 amp charge the difference was much worse.. I expected to see a .6 volt drop but it was a logarithmic progression rather than the expected linear one.. And went up to .9v difference
So folks.. get busy running checks. !
I fitted 300w of solar panel on the roof when we got the van, and used a fairly up market controller with digital display.
From day one there was a discrepancy between the voltages displayed on the solar controller and the vans control unit.. I put that down to a not very accurate read out on one or other of the displays.
Whilst doing the fitting I noticed the feed wires from the Sargent charger to the battery(s) had gone hard and crispy towards the lower ends indicating how hot they had become at times
I just cut them back to good clean wire and refitted*
At the Thetford meet this year I bought a very nice battery condition display unit from John ( @Don Quixote ) and that showed again a discrepancy between the solar controller and the actual battery voltages.
I decided to run a couple of checks and discovered there was indeed a .3 volt** different when the charge or draw was at about 5 amps.
Given the only thing between the two check points was about 3 metres of wire I was quite concerned.. Initially I thought maybe I had made a mistake and connected the solar controller output to the wrong wires.. That was soon dismissed though
Yesterday I doubled up the size of the originally fitted wires from the Sargent unit to the batteries ( To which I had connected the solar feed in )
The difference in voltage read out immediately became 'acceptable' at .01 volts when 5 amps were drawn
Conclusions:
1) * Inspection of the original feed wires from the Sargent charger to the battery(s) should have raised my suspicions from the go that the wiring was not 'man' enough for the job,, but in my defense they appeared to be the correct gauge, were original fit, and I just thought that someone at some time had done something daft with an after market charger and cooked the wires a bit
2) Those wires had got hot. Heat is bloody dangerous !
3) This is the bit that really gets me..
Apart from the obvious danger of wires getting hot there is also the issue that any type of charging system ( mains, engine or solar ) was being fooled in to thinking the batteries were reaching a higher state of charge than was the case.. So what ?
Well the charger ( what ever source ) will shut down and reduce the amperage fed to the batteries if said source believes the charge state is good.
For the past two plus years the solar ( and other ) system has never fully charged the battery(s) as it THOUGHT a fully charged state had been reached
** At a 10 amp charge the difference was much worse.. I expected to see a .6 volt drop but it was a logarithmic progression rather than the expected linear one.. And went up to .9v difference
So folks.. get busy running checks. !