Advice on a charge controller please :)

[m_c]

A CDI should get around 14.2V at the battery terminals after being running for a short period. If you're not, it's most likely the main positive loom has got corrosion in it at the starter terminal. Check to see if you're getting over 14.2V at the alternator, then check for volt drop between the battery positive and the alternator main output.
You can either remove the loom, drill two holes in line with the end of the cables and using a blow lamp/oxy-acy torch run plenty solder through the crimps, or just get a new loom.


14.8V?
That's really only needed if you're bulk charging the batteries after they've been run down. And to acheive that voltage on that much capacity, will take a lot of current!
Provided the solar is doing a good job of reguarly keeping the batteries around 13.2-13.5V, the continual trickle charge should keep them conditioned.


You're not using AGM batteries are you?
If you are, then you'll need some way of limiting current when charging, otherwise they'll pull every last bit of power from the vehicle they can when charging. They absorb charge far quicker than conventional lead acid batteries, and the voltage doesn't rise until they've got that charge.
We maintain some vehicles that have had AGMs fitted on the vehicle, and I've seen a flat one sit pulling 20A from a battery charger for 30minutes before the voltage even creeped above 12V, and if you jump start one, you can hear the load on the alternator and the voltage gradually creeps up.

[blackburn mark]

morning MC... i wasnt going out in that rain yesterday!!... the battery is showing 12.3v before startup so i think that is on its way out (the little indicator on the battery is confirms this)

its showing 14.23v when its running, thats stable even if i increase revs, this has me thinking that maybe the van would push it at more like 14.4v and the tired battery is pulling it down ? ill look into this.

im looking to put standard wet batteries in, they sell as deap cycle 125ah but im guessing they are just re labled as such (ebay...love it)
iv taken the advice that the cheaper the better... with good charge control should last quite well... nothing like AGM's and the like but they really are a tad pricey

iv done a bit of research on the voltage issue, an article by a guy who has lived in his van for 8 years (and never used a genny) is charging at the much higher voltages, holding that voltage at least an hour passed the usual current drop (tempriture compensated)

i think most charge solar/wind controllers and car/van charge systems aire on the safe side (totally understandable...zero maintainence)
so i really want to hang on to the option to push the volage up should the need arise

i think the world is split on the issue of charge voltages for standard wet lead... i think having voltage options a hydrometer and a pen and paper might be the way to go :)