Schneider Electric has discovered a material non-conformance with respect to hardware used in certain 100 Amp thru 225 Amp QO Loadcentres with CSA markings manufactured between October 23, 2001 and January 14, 2002. This non-conformity involves the potential for a loose bolted connection on the neutral bar in the mains base assembly. If a loose neutral connection was to occur it may result in higher or lower voltages than normal on a single pole branch circuit(s). Therefore, a potential for PROPERTY DAMAGE exists for sensitive electronic equipment.
For more info see following PDF Documents. ET00759-01.PDF
Thanks to Tony Moscioni for providing this info.