I have a few retrofit breakers in my system (GE AK-25 c/w Amptector 1A trip unit). When I use PTW32 to run the arc flash study, I found the trip/delay time of these breakers are only 2 or 3 cycles. I was told that I don't need to add breaker opening time to it. Has anyone seen such a fast action in your study before? Thanks in advance!

Not for that one, you need to add operating time, amptectors are more like 7 or 8 cycles for INST if I recall, contact GE for actual trip times or better yet, upgrade that Amptector 1A to something that actually works.