I wanted to follow up on my Victron system with some setup instructions I received from Victron on how to utilize my on board charger.
A couple of notes to understand the situation so this might be useful to someone:
- I already had the charger mounted under hood for use with my lead acid starting battery and +/- wires running back through the firewall for powering my fridge etc. prior to this latest addition of a lithium battery in the cargo area.
-I really appreciate the ability of the charger to plug into 110 the day before a trip and get the fridge/freezer down to temp with all the food and drink loaded up without using battery juice overnight to do it. I also like to plug the vehicle in and have it maintenance charge during months when it is standing in storage.
- I didn't want to run a second +/- set of wires from the charger back to the lithium battery to be able to maintain the battery now responsible for all the aux loads. I also didn't want to relocate the charger to the rear of the vehicle because I like the way I've located the shore power plug into the front bumper (see pics in prior posts) and it saves space.
The three points above left me with the question of how I might be able to use the same +/- feed that goes from the charger and starting battery back to my new DC-DC charger then into the Lynx distribution hub then into the new lithium battery with everything playing nice.
The challenge with leaving the charger inline as I have it installed (@joltman was nice enough to explain to me at one point) is the DC-DC charger will see the charger power *turn on* and send it's full charge downstream to the aux battery, it thinks it has all the power it needs to charge the aux battery but in fact will be pulling the deficit (difference btw charger output 13amps and DC-DC charger output of 30amps) from the starting battery itself. This isn't a problem when the charge is coming from the alternator because it is more than 30amps so there is no deficit that needs to be made up by the starting battery.
I took a longshot and posed this issue to my Victron distributor who gave me such a thorough step by step solution that I thought if anyone else out there is thinking of this situation it would be useful to share. I have completed the setting changes and all seems to work as described and I'll report back if I have issues. Until then here is what I did to program the system.
From Victron:
So starting with the IP65 charger...
(this is the less important part to get right, but it's still important)
Hit settings in the upper right hand corner
Then go to Charge Preset and hit Custom.
Scroll down and ensure that Advanced settings is turned on.
At this point, it should look like this...
Then Click on Advanced battery settings
Turn on Expert Mode
Now look at these 5 red arrows and make all the values match
Now scroll down to the Absorption section and make the settings match this following image...
That's it for that charger.
Now go to the Orion DC/DC charger
Hit the settings in the upper right
Hit the Input Voltage Lock-Out settings
Enter the values as follows...
Hit OK and it should look like this
Hit Battery Settings
Select Preset / Smart Lithium LiFePO4
All these settings should automatically load... but I arrowed a couple of things to double check
Now here's the important part that might possibly use a little tweaking after you test it...
Hit the back arrow and hit Engine shutdown detection.
Make all of the settings match this screenshot.
Once you have done all of that, you should be all done.
Plug it in and test it. The IP65 charger should start charging the starting battery, and then if that voltage gets up to 13.8V The the Orion will immediately turn on and start charging the Lithium battery. If the voltage is rising slowly, then the Orion will start 120 seconds after the starter battery gets to 13.6V.
Because the Orion draws more than the IP65 charger, that starter battery voltage will sag down to 13.2V (as measured on the input terminals of the Orion).
It will remain at that voltage until the Lithium battery reaches full charge (or nearly full charge) at which point the starter battery voltage will rise to 14.4V.
The charger will complete that cycle in two hours, after which it will drop that voltage down to 14.0V.
If you leave it plugged in for a long time after both batteries are full, then the starter battery voltage will further be reduced to 13.8V
Let me know how it goes.