Pre-Ohmic sensing Question on older series

Hello, we got a second hand. 4x4 GS table, Hypertherm 85, AVHC blue screen, driver software 4, plate marker.

We just got everything up and running and are in practice/production mode. We were plate-marking an 8" Diameter fairly intricate logo then cut out the circumference. (4' x4' 14ga aluminum) the first cut plate-marking quality was poor, we assumed it was from the sheet moving. We reduced the down force on the PM and weighted the non-working side of the sheet we were cutting. 2nd attempt the PM was working great and when it switched to the plasma it cut from 0°-90° (1/4 of the circle) and the sheet lipped up and the plasma tip hit it and cut the piece in half. My main question is i know we don't have Ohmic sensing but i thought the plasma and AVHC had a voltage sensing that would reduce this from happening. Is there anything we can do to reduce this? and is it a common occurrence or was it just beginners luck. I have reached out to see what the upgrade is and its quite expensive, but may be an option for the future. any help would be appreciated.
Thanks in advance

 

There is a good video on the operation of the AVHC found here

 

that is exactly what we needed, thanks!