Hello Jaleel,
you can insert the DS3 PA on an alive C7200.
Only warning:
verify with sh ver how many BW points are consumed by slots 1,3,5 and how many by slots 2,4,6 (this is for a C7206).
Choice a slot where more points are available.
After insertion the PA will be powered but the interface needs to be enabled (no shut).
You can lock the PA moving the lever to the lock symbol.
Hope to help
Giuseppe