methods
1 GW
It may just be that the main output caps were drained and what you heard was them charging from your pack when it was plugged in - I don't know - as I have not played with these much. That is the same sound you hear when you plug a controller into the pack - POP. Usually accompanied by some burn marks on your connectors.
Lets say worst case you actually blew electrolytic caps - it makes sense that it is still working afterwards. Those act mostly as smoothing caps so the output will still produce your charge power - just a little bit noisier. If you look inside you should see fuzz from the popped caps (if you popped any). The top of the caps are always scored so that they will blow open at that point. Very easy to see. Have a look
Should not be a problem plugging a pack in first IMHO - but again - I have not played with these much yet. "Smart" chargers are always less smart in my opinion than a simple CC/CV supply. Just more to irritate us and go wrong.
-methods
Lets say worst case you actually blew electrolytic caps - it makes sense that it is still working afterwards. Those act mostly as smoothing caps so the output will still produce your charge power - just a little bit noisier. If you look inside you should see fuzz from the popped caps (if you popped any). The top of the caps are always scored so that they will blow open at that point. Very easy to see. Have a look
Should not be a problem plugging a pack in first IMHO - but again - I have not played with these much yet. "Smart" chargers are always less smart in my opinion than a simple CC/CV supply. Just more to irritate us and go wrong.
-methods