I have a travel trailer with 2x100Ah dragonflies. It came with the victron mppt 30/10. The converter it came with was mismatched and didn’t support lithium, so i swapped it for an IP43 smart charger. I also have smart shunt. They are all ve Bluetooth networked.
When i am plugged into shore power, and the charger is on, i get 0w from mppt during the day. Is there a way to use max solar watts, and then supplement charging from shore power? This seems like it should be the default behavior. Any help appreciated.
The IP43 chargers sadly have been forgotten for years by Victron in terms of integration, seems that not enough people complain loud enough about that to make them give that a priority above zero.
In case you want MPPT taking priority over the IP43 you’ll have to set the charging voltage parameters on the IP43 lower than on the MPPT, so power will flow from the MPPT instead of the IP43. Also you have to make sure that both use the same temperature for voltage compensation (either turn that off completely, if your battery allows it, or add a probe to the SmartShunt and have transmit temperature through the VE.Smart network) - else the MPPT could decide to see a higher temperature than the IP43 and reduce voltage more, leading to the problem your post is about.
Other option, in case your MPPT has a built-in relay, could be to wire the IP43 external enable through that relay and pick relay settings that disable the IP43 in case the MPPT should be able to provide enough power (panel voltage could be a candidate for this)… but that solution is crude and either/or, instead of giving the MPPT priority based on voltage.
Last option is to get a GX device and en-/disable the IP43 using Node Red, depending on the status of the MPPT (and possibly SoC, to not have the IP43 kick in on every little cloud). Also on/off, but a little bit more “intelligent”… and more expensive.