There is minimum compressor speed, usually at ~2A current. It cannot go below 2A and if it needs to go even slower, then it trips. It's normal to trip, especially if temperature is set 27C-30C.
Your AC is cooling excellent, no problem. Just enjoy. Run the AC at 18C for an hour or two just for double check, as it should not trip at lower thermostats (18C-24C).
PEL cooling is pretty awesome in general.