Piezoelectric Arc Movement

Cathode Root Movement

In Figure 8.6, there is not a very large
difference in the time of rapid arc motion
despite significantly different contact
velocities. In this case it is possible that the
delay is caused by the transfer of the arc
from the moving contact to the arc runner,
where factors such as gas flow have a strong
influence. The cathode root on the fixed
contact shows a more gradual movement for
both the piezoelectrically operated and
constant velocity contact systems. The
constant velocity system shows an initial
slowarc rootmovementof approximately 5
ms followed by rapid arc motion at the same
time as the anode.

Reference: Piezoelectrics in Circuit Breakers: Design & Test Paperback – 24 Dec 2014 by Dr Kesorn Pechrach Weaver PhD (Author)