Is it ok or even desirerable to ground the ground bus-bar in a sub-pannel just to be safe or more safe?

Question

Is it ok or even desirerable to ground the ground bus-bar in a sub-pannel just to be safe or more safe?

Answer 1

Shouldn't it should be grounded to the busbar in the main panel? If you install a subpanel it should be grounded.

Answer 2

Bear in mind that a subpanel should have two bars - a neutral bus bar and a ground bus bar.  They are electrically NOT connected at the subpanel.  All neutrals (white wires ) in the sub go to the neutral bar, while the grounds go to the  ground bar.  The box enclosure is bonded to the ground bus only.  To do otherwise IS NOT SAFE.

The neutral at the subpanel is not the same voltage as the neutral at the main panel where ground and neutral ARE connected.  Because there is a voltage drop on the neutral back to the main, the subpanel neutral could be several volts (or more) different from the zero volt reference at the main.  This voltage would be imposed on all exposed "grounded" parts coming from the subpanel. Not safe!

A subpanel should have its own grounded conductor for removing faults.

  You should consult the NEC for rules on properly sizing subpanel ground conductors.