[paw_by_paw]

Hi Guys, To All Battery Fundies Out There.
I have a off road caravan with a Inteelegent charging Unit in it with two 102 A/H Delco Voyager Batteries.
My question is:
Should you drain the batteries flat at some point in time
Secondly I do not know how this charging system works meaning is it a trickle charger and will the intellegent part first charge a single battery and then switch to the other battery or will it attempt to charge both at the same time
How long will it charge to complete both batteries
Someone suggested it should not take longer than six hours
My experience is that a deep cycle battery takes much longer to reach full capacity.
My batteries were flat , very flat and the charger has been running now for 48 hours non stop and the one battery does not show the green indicator as for good battery- it is still on the black circle meaning it still charging
Any suggestions or technical aspects will help.
Thanks

[SimonB]

Ok I'm sticking my neck out here based on a fair bit of research I have done I could be partly qualified to answer. but here goes

Should you drain the batteries flat at some point in time

No, flattening batteries is not something you should do as a matter of course. Doing so shortens battery life. Batteries only have so many duty cycles in them - the deeper the discharge the fewer duty cycles.

Secondly I do not know how this charging system works meaning is it a trickle charger and will the intellegent part first charge a single battery and then switch to the other battery or will it attempt to charge both at the same time

Trickle charger does not imply intelligent, although an intelligent charger will have a trickle component. Trickle chargers just switch to a maintenance charge when a battery is fully charged, whereas an intelligent charger has various stages depending on the state of charge of a battery. A charger cannot determine whether there is one or two batteries attached, and has the potential to confuse the dumber of the intelligent chargers. I am of the opinion that two batteries in different states of charge should not be charged together (this opinion could be flawed, so someone else is welcome to fire away)

How long will it charge to complete both batteries
Someone suggested it should not take longer than six hours

A LOT longer I have a battery on charge at this very moment while testing my new systems. After 6 hrs it hasnt reached 40%

the one battery does not show the green indicator as for good battery- it is still on the black circle meaning it still charging

My experience is to ignore the indicators. Use a multimeter.

[4ePajero]

I would charge the two batteries independently.
Disconnect them from each other.
This way you should get an indication of their condition.
It is not advisable to connect two very different batteries in parallel. Different includes batteries with similar rating, but diffirent internal resistance (condition).

Sent from my iPad using Forum Runner

[paw_by_paw]

Hi Marius,
Thanks for your reply. The batteries has been on charge for 72 hours now and only the indicator panel shows it is charging at 13.4 volts now. I would therefore assume that it is a trickle charging effect.
So the charging is nearing the end of charge now- So I hope at least.
I will go and get a multi tester .
My question is what I be testing then
Disconnect each battery and test the voltage at the wires
Or will I be testing the battery voltage
Will a halfull battery not test 12v even half full
Should I rather do a load test then
Kind Regards

[SimonB]

Gerald

The charger should indicate when it is beleives that the battery is full.

You also have a thing called the surface charge which will indicate a higher voltage that is actually the case. I'll have to dig up my notes on this

[Kennekam]

I use a CTEK charger which manages the whole process. It will charge when necessary, trickle feed and even refresh when needed. Just leave the battery connected. Best buy ever.