vacuum cleaner trips AFCI

I recently started including a disclosure in my reports about certian types of vacuum cleaners tripping AFCI breakers. Has anyone else had this issue regarding the AFCI’s.

Are these grounded (3 prong plug)? It might just be an internal short in the vacuum.
Otherwise I think it would be heplful to know if the problem was AFCI brand specific.
There is a certain amout of voodoo in the algorthym they use to detect arcs and some brands may act differently than others.
I am not sure the “series” arc detector is actually in the wild yet and that is the kind of arc you get from the motor brushes.

Here’s a link for Square D.$file/VacuumFAQ0502homeowner.pdf