I recently upgraded my RV to LifePo batteries (two 100AH). While doing so I upgraded the converter/charger to WFCO’s auto sensing unit. I also installed a Victron Smart Shunt. I fairly quickly discovered a now known issue where the WFCO unit does not do a good job of actually detecting lithium properly and never goes into a proper bulk mode. This means that I would never see more than about 10-11 amps while charging. Once the batteries would eventually reach full charge it would float and maintain 13.6 volts and a fairly consistent small positive amperage to the battery according to the Smart Shunt (this is from my memory).
Because of the low charging amperage issue, I decided to remove the WFCO converter/charger and purchased two Victron IP22 30Amp Smart chargers. I was able to place them within 5 feet of the batteries where the WFCO unit had been over 20 feet away. I hooked them all up and was thrilled that they delivered 55+ amps during bulk mode.
Unfortunately, I have discovered something that strikes me as odd once they go into float mode. The voltage stays fairly consistent with only very small fluctuations like 13.49 to 13.51 volts using the lithium setting. However, the amps bounce around like crazy. They fluctuate from around -1 to +2 constantly. As in, they will bounce around in that range a couple of times every second. I have attached a screen shot showing this behavior in the trends area of the app. I have a small load present at nearly all times for my RV.
Is this normal? I am 99.9% sure I did not see this behavior when I was using the WFCO unit. Are the IP22’s not well suited for the task I am asking them to do?
Things I have tried with no change. I have removed all items from the VE network, unplugged each of the two IP22’s one at a time to see if one of them was behaving badly, changed from the lithium preset to custom ones trying float voltages of 13.6 and 13.8, added slightly more draw by turning on lights inside the RV.
Any thoughts?
