If in "test" mode The OPUS will charge them then discharge them then charge them. all automatically
No need to use the "charge" mode then change the mode to "discharge" The OPUS quick test (IR) is not really usable inconsistent results
It is not recommended to use a any powerwall without a BMS. But it has been done.
Monitoring the voltage: would need to check Total battery pack voltage and the cell voltages. Several times a day.
There are other BMS's besides Daly perhaps one of the other BMS would work and many are less...
Welcome, Many have started out the same way.if you haven't read the FAQ thread https://secondlifestorage.com/index.php?forums/frequently-asked-questions.42/ read it will answer many of your questions.
Charging the cells in bulk to 3.6v will really shorten your turn around time. Charge them then place in your Opus's on test mode. 3.6v to 3.7v happens fast. Even faster if you remove the cells after they finish the discharge portion of the test mode. Then Bulk charge the cells back up to...
Continue to research lots of reading here
Congrats, make sure the switch located on the back side of the Opus inside the case is set to 3.7v. I have an Opus 3400 setup for testing LiFePO4 cells using 4 external 26650 cell holders. I have tested several hunderd A123 LFP 26650's.