Force smart alternator to 14v for leisure battey charging.

[Jarvie.I]

How to get smart alternator up to 14v when vehicle battery is fully charged and leisure batteries are low after being parked up for a few nights running fridge. diesel heater, lights phone chargers etc. I have tried putting on hi beam, full fan speed for van heater can't get the 14v to kick in which I need for the Agm twin batteries. Any ideas how to get the leisure batteries charged while camped up static for a few nights.
I believe the smart alternator looks at van battery along with load required to decide when to ramp up volts to 14v.
VW T6 2016 plate.
Sterling DCDC Charger BBS1230.
Thanks in advane

 

[Dellmassive]

not sure about 14.0v exactly.

but blower on speed2 will get you above 13.0v

lights on full or AC on etc will get you high 13`s.

. . . . . .

the charge rate to you LB`s will be determind from the cable thickness aswell, as volt drop will be an issue.

so drop some pics of your install.

where is the sterling fitted?

where are the LB`s fitted?

what lengh run? what size cable?

etc etc


got some voltage readings for us to go on?


FYI . . . if you have a smart ALT, disconecting the sensor at the battery temporaily will get you 13.8v from the ALT.

 

[Jarvie.I]

Sterling unit under drivers seat, Leisure battery under drivers seat, 2nd leisure battery behind drivers seat, So cable distances = Minimum, heavy battery type cables linking everything from vehicle battery to the DC Charger.

 

[Jarvie.I]

Volts reading and amps readings on leisure battery. Pics of lights on Sterling unit.

 

[Dellmassive]

so 13.0v coming in from the engine bay.

LB 12.2v and charging at 12.3A


...



looks like a 30A charger.

but you will need a higher voltage at the Stirling to get more Amps into the LB.



can you get two voltage reading when the engine is rinning.


the voltage across the starter battery (with the heaters or lights on)

and the voltage at the sterling starter battery terminals.



that will show you the volt drop across that cable when pulling the 12A.


.

 

[Jarvie.I]

no the 12.32 is the voltage at the leisure battery, the 0.5 is the clamp meter reading So I see it that it's only charging at 1/2 amp. When charging with a smart mains charger the voltage is 14 and I set the amps to 12 as per Agm charging recommendations. Issue is van battery is charged so Smart alternator not switching up to 14v, so Sterling Dc charger doesn't do its thing at charging high amps.

 

[Jarvie.I]

So couple photos of mains charger set at 12 amps, 1st hour or so it's around 13v then towards end its up to 14v.

 

[Dellmassive]

Is the sterling possibly goosed?

Have you checked all the connections and good and not burned ?

Good ground connection?

 

[Jarvie.I]

Is the sterling possibly goosed?

Have you checked all the connections and good and not burned ?

Good ground connection?

It might be. from reading on Google on the way the DcDc chargers work- it is supposed to boost the voltage up from the vehicle battery to suit 14v output to leisure batteries.
So if vehicle battery is fully charged at 13v and engine is running- the Dc Dc charger should still donits job of charging depleted Leisure batteries- this doesn't happen on mine- Leisure battery voltage remains at 12.3( depleted) with engine running. I emailed Sterling and await a reply. Will provide update- in case it helps others on forum.

 

[Jarvie.I]

So bit more info - from the manual. see pic. Looks like i will try running an ignition feed wire- hopefully when engine is running while stationary in campsite it will kick the charger into charging mode. off to halfords for a piggy back fuse and then the fun of stripping out the whole front cab to run cable.

 

[Jarvie.I]

Ok so, I rejigged my current loop sensor to monitor the current going into the leisure battery. Checked with mains charger at 2 amps and 4 amps, panel meter measures correct levels. Started up van and the sterling Dc charger decides its now going to work. This is before running an ignition feed to the dc charger. Is Sterling unit being temperamental, maybe I have tightened a loose wire in rejigging or something. Will go with it for now and see how she fares. Ignition wire remains a future option.
Pic of Sterling unit running correctly at 14v and my Induction display panel showing what the Dc charger is pumping into the battery.
Last photo shows the charger backing down- probably because it has found the Leisure battery to be fully charged, panel meter dropped down to 0.2Amps.
All for info if any help to others.

 

[Jarvie.I]

Just noticed that the two photos showing the DC Charger appear to be showing different battery types- 1st one Lithuum, 2nd one gel. The battery is AGM, so maybe issue is with Sterling unit getting battery type wrong. Maybe need to check setup incase it's been corrupted.Next on list to do.
Happy if anyone can advise on setting the battery type on this unit.

 

[Jarvie.I]

Got it set to AGM 14.6 for my L36-AGM 95Ah batteries. The charger leds displays different info at different times Start up and normal running modes.

 

[Jarvie.I]

Sterling techs confirmed need an ignition feed wire to the DC DC charger to wake it up when van has been stationaryvfor a while. So it's a task getting a cable from the centre column fuse box across under the floor to under the drivers seat, ripping out seats, lifting rubber carpet etc.
Alternative thought was to fit a mechanical type 60 min time switch with single contact somewhere accessible near / under the seat connecting a 12v feed to the ignition connector on the Dc charger.
To charge while being stationary for a few nights just start the engine, turn dial on timer to 30-60 mins - timer stops automatically if you forget to turn it off.
2nd similar thought was to just connect the ignition connector on the Dc charger to a 12v feed under the seat via an accessible fuse holder and just pull the fuse when not required and then when stationary- start the engine with the fuse in place- remove fuse once engine stopped.
Bit of a bodge but would work as long as all 12v wires fused correctly.
Time to ponder.
This type of mechanical timer- no electronics required:-

 

[Dellmassive]

Or swap out the sterling for a more modern charger.

The new Renogy and victron dcdc charges use automatic detection algorithms.

 

[Hakon]

I've a T6.1 and have noticed whilst looking at Carista, that the voltage seen by the ecu runs at 14v ish continuously when I have the tow ball mounted bike rack hooked up with the associated electrics.
As a result the starter battery is allegedly charged to circa 95-98% when the bike rack is fitted, alternatively the battery charge is rarely gets above 80% when not fitted.

 

[Jarvie.I]

I suspected that my twin leisure batteries weren't getting a full charge so I wired up a couple of tails from + and neg from opposite batteries to allow a mains charger to connect- i noticed a big difference using the mains charger.