CTEK 250S connection with Smart Alternator

Yes duncanm, I saw the manual saying so as well but my concern is as Kevin mentioned regarding non standard connection.

I might do some testing while at home next week - discharging the service battery to certain level; measure the battery voltages; then connect the trailer to the car then measure the voltages on the batteries again.

I have attached two pictures to show how the connection like - hope you can see the writing.

Cheers
 
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ok - then recommendation would be to first monitor the charger to see if it does indeed try to charge the service battery with the ignition on (and engine off). Look at the LED's on the charger.

If so, then add a switch between ign and relay to isolate the ign signal from the relay when required (so relay remains switched to the solar panel position shown in https://www.prosolarpower.com.au/store/p22/Ctek_D250S_Dual_for_Variable_Charge_Alternator_PSP.html)

Don't bother to add yet another relay.
 
That's the plan, cheers
 
Well, got the chance to do some testings today:
The car had been running on the freeway for about half an hour when I got home and I supposed the starting battery should be fully charged?

Turned on the light of the trailer for a while to discharge the battery to about 12.xV, then connected the trailer and the car via the anderson plug with the key in "On' position without the engine running - the charger indicated charging from "Solar" and I could see the voltmeter reading climbed rapidly!

Turned the engine off and the voltmeter showed about 12.9v at the anderson plug of the car. Started the engine for about 6 minutes and the voltmeter showed 14.5xV all the times (never dropped).

Changed the connection point of the CTEK from "Solar" to "Alternator", connected the 2 batteries again. The charger showed "On" only when the key was in "On" position without the engine running. Started the engine and the CTEK showed charging the service battery from alternator after a minute or so.

Conclusion:
The CTEK does not separate the servicing and starting batteries while the 2 batteries are connected via "Solar".
The CTEK does separate the servicing and starting batteries while the 2 batteries are connected via "Alternator".

Remaining question:
Does my MY14 2.0D CVT Outback has a smart alternator? :poke:
Or had I not run the engine long enough to allow the "smart" alternator to stop charging the starting battery? :o
 
Thanks Ratbag. Its good for me to know how the CTEK behaves as well.

I may leave the connection at "alternator" to see if it can fully charge the service battery or not - particular when I get the fridge later then decide on what to do next. :discomonkey:
 
pretty solid conclusions there.. good work.

It'll be interesting to see if the Alt output ever drops off..
 
duncanm said:
It'll be interesting to see if the Alt output ever drops off..
Click to expand...

I think so too...at this stage the I think the only way to know is to test it for long time - the question is how long
 
PauSum said:
Conclusion:
The CTEK does not separate the servicing and starting batteries while the 2 batteries are connected via "Solar".
The CTEK does separate the servicing and starting batteries while the 2 batteries are connected via "Alternator".
Click to expand...

That's what I would expect. However, the solar connection at some point in voltage drop from the source must disconnect otherwise if a solar panel were connected it would feed power back to the solar cells. This is how it works at night with panels connected otherwise the cells would warm up due to the reverse voltage being fed to them and they don't - I checked.

Good idea to connect to alt input and see what happens!
 
Kevin said:
That's what I would expect. However, the solar connection at some point in voltage drop from the source must disconnect otherwise if a solar panel were connected it would feed power back to the solar cells. This is how it works at night with panels connected otherwise the cells would warm up due to the reverse voltage being fed to them and they don't - I checked.
Click to expand...

Thanks Kevin for the good tip!
 
or there's probably a diode to prevent a reverse current from the solar connection.
 
Kevin said:
or there's probably a diode to prevent a reverse current from the solar connection.
Click to expand...

Dont know. Doesn't mention in the CTEK book as well...
 
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