20' Series How to tell if car charging Expanda batteries?

Wombat6

Member
Aug 27, 2016
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Melbourne
We have a 2016 Expanda caravan. Due to problems with our previous tow vehicle we have not used the caravan much in the last 18 months. However, we have just bought a Patrol and last week had a towbar and caravan electrics installed so today I connected it to make sure everything worked. One extra thing I had fitted was an Anderson plug to at least better power the fridge whilst driving. Today I then disconnected the fat accessory cables from the caravan 12 pin plug and wired them into an Anderson plug and connected it all. Finally now the fridge runs from the car which is great but how can I tell if the car is charging the batteries? Is this meant to show on the drifter monitor because it just shows discharging? Or is it just like charging from solar which doesn’t show on the drifter? We’re heading off on a weeks holiday before Easter and I wanted to make sure all was well with the van.
 

mikerezny

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Sep 11, 2016
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Do you have a Setec ST series III power supply?

If so, first off, you will need to have the battery switch on.

It will be difficult to check if the car is charging the van battery unless you have a multimeter.

If your van has not been modified. 12V from the tug is fed into the AUX input terminal of the Setec via pin 2 of the 12 pin plug.

First step is to read the voltage on the tug 12-pin socket across pins 2 (12V) and pin 3 (earth).
Check without the ignition on and then with the engine running.

If you get 12V there, then plug the van in, and then measure the voltage across the battery terminals. If the battery is being charged the voltage will be higher when the trailer is connected and engine is running.

cheers
Mike
 
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mikerezny

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Sep 11, 2016
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My Drifter reads car and solar input
Yep, I expect it should. For solar, the negative wire from the controller has to be on the correct side of the current shunt. I.e, not connected directly to the negative terminal of the battery. If the car 12V is connected correctly to the Aux input terminal on the Setec, then current from the battery will go through the shunt and thus measured by the drifter.

cheers
Mike
 
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Wombat6

Member
Aug 27, 2016
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Melbourne
Mike, as soon as I get a chance I will look at your suggestions. However, whilst much of our caravanning over the last 18 months has involved powered sites, my impression is that the drifter control panel (factory wired) only sort of monitors charging from the non mains power chargers. Currently it has been sitting in the sun for a month and a half and the drifter control panel yesterday morning did not show any battery charge despite it in theory receiving charge from the rooftop solar battery. Then I plugged in my new Patrol (maybe connected for 10 minutes tops) to check the trailer plug and despite the drifter still saying discharging, tonight when I checked it was saying the batteries where at half charge. Further, the battery voltage is 12.9V.

Once before I had an external solar panel plugged in for many hours which the drifter control panel did not show but then after plugging the car in for a short period it then showed full charge. Riddle me this?
 

Duncanblake36

Active Member
Nov 17, 2016
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I was the same. Not sure on your setup but I installed a Ctek D250S DC to DC charger next to the van batteries then connected this using a Anderson plug at the back of the Hilux. Works a treat. That way when you arrive anywhere you can always guarantee that the batteries are fully charged. We do a lot of off grid camping so also allows us to charge the batteries with hilux is they get low (which has happened once or twice!)
 
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Drover

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Nov 7, 2013
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I just rely on my solar and its always worked, so if you have solar fitted on van I assume you should shut it down or the supply from tug if going thru a DC/Dc unit would cause a conflict and each would see the other supply as cut charge accordingly.............same as two panels with seperate controllers.... I look at it as if the tug is running my Engel, Aux Battery and the Van fridge and all the other stuff in the vehicle then charging the van battery is just that bit more of a load which is easily taken up by my van panels.
 
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