Hello,
Is it OK to connect Orion-Tr (12-12-30) and MPPT (100/20) to the (second) battery in parallel or do I need to have a switch so they don't both connect at the same time?
Cheers
asked
MPPT and DC-DC in parallel?
Yes, you can do that. They can't hurt one another.
You may want to fiddle with their settings so that one takes charge priority, but that shouldn't be too hard to work out.
Awesome thanks. I just found this one as well so all good!
https://www.victronenergy.com/upload/documents/1.6KVA-12V-MultiPlus-230-Volt-system-example-4-PIN-VE-Bus-BMS-Lithium-Orion-Tr.pdf
What's the best way to have one Victron charging device "take charge"? Offset the absorption voltages?
Interesting this one. I have same setup currently with an AGM battery. I found the B2B would go into float setting but the solar MPPT would still be in absorption mode keeping voltage at 14.8v. The second issue is with charge current. On a sunny day your solar charger could deliver 20 Amps and your b2b 30 amps. This would be to high for AGM battery. I end up disabling the solar in setting when on the road if the battery is fully charged.
It's all in the settings. If your B2B's are lower than the mppt's then it will complete it's charge cycle first and the mppt will then complete it's own. 14.8V is quite high and probably unnecessary. If you don't like the Absorb cycle, then change it to something that you prefer, maybe a fixed time or even none at all.
Your batts are only fully charged when they can't accept current (or very little). So switching off the mppt when it's already wound itself back to hold to a V profile seems somewhat futile. Victron mppts can be power limited anyway, but a typical solar day starts slowly and winds up, and it would be a rarity for a balanced system to exceed the max recommended charge rate. It can be done though in certain circumstances, but usually V will take over and the system will self limit.
If you ever see excessive charge into the batts, then reduce the charge V's to where it doesn't happen. The batts will still charge, just slower.
I will have to try some setting changes later. My solar in the past has been charging at 10 amps. So with the B2B running as well I would have thought the charge current would be well over 10 amps. The problem is the b2b does not record the current so I do not know if it is putting in too much current. Although the AGM battery could take a 30 amp charge it's ideal to keep this at 10 amps. I have lithium being put in at the end of the month so will have to change it again.
