These are not necessarily grounded conductors. In the case of a 208, 240, or 480 volt coil this conductor is ungrounded. Also, there's an exception in NEC 250-21 (3), but these are fairly unlikely circumstances (d) If you want to change it, it can be accomplished with jumpers, and a material outlay of less than a dollar.
A potential hazard with the O/L contact switching the grounded wire is that if the wire from the contact to the coil (sometimes just a jumper, but often extends to other controls) becomes grounded, the circuit will not respond to the open contact. This can allow other devices on the same controls to run, and can destroy machinery and people.
(no more edits, sorry guys)
[This message has been edited by electure (edited 03-04-2001).]
[This message has been edited by electure (edited 03-04-2001).]