Will the current NF600SFHB fit in pre series E1 (Before October 2008) NF panels?
Customer has an old NF panelboard with KC sub-feed breaker and wants to remove it and add the NF600SFBH to be able to change to an H frame 100A breaker.
No, the NF600SFBH will not fit on the pre series E1 NF panels. Series E1 panels were introduced in October 2008 . Pre Series E1 panels had no series ID.
NF panels were introduced , replacing NEHB panels, in 1994.