Re: Overcurent devices allowed!
You are right: the same model of panel can be used for either application.
If there is no neutral bar (i.e., 3-phase loads only), then it is a ?Power Panelboard.? If there are no breakers with a rating of 30 amps or lower, then it is a ?Power Panelboard.? If a panel fails these two tests, then the odds are that it is a ?Lighting and Appliance Panelboard.? Specifically, if there are 5 breakers (really, 5 pole spaces, but the rule is 10% of the overcurrent devices) that use the neutral and that are 30 amps or under, then the panel is a ?Lighting and Appliance Panelboard.?
The limit of 42 overcurrent devices applies only to the ?Lighting and Appliance Panelboard.? When counting up to 42, a 2-pole breaker counts as 2 overcurrent devices, and a 3-pole breaker counts as 3 overcurrent devices.