Panelboard orientation inconsistency

[pv_n00b]

Is it inconsistent in the 2020 NEC for 408.43 to prohibit panelboards from being installed in a face-up orientation but 240.33 allows circuit breaker enclosures to be installed horizontally? A circuit breaker enclosure is not defined in the NEC and a panelboard does kind of sound like it could be considered an enclosure for circuit breakers.

 

[Dennis Alwon]

How about explaining that some more. A panelboard face up is very different from a panel being installed horizontally

 

[pv_n00b]

Ask the NEC, another inconsistency? Neither "face-up" nor "horizontal" are defined in the NEC. My interpretation based on the usage in the text is that horizontal and face-up are the same thing.

 

[rnatalie]

The amplifying (non-normative) text makes VERTICAL and HORIZONTAL refer to the orientation of a panel mounted ON A WALL type surface with (not to mention one of the largest homebuilders in the nation used to install ITE-pushmatic panels vertically but upside down so all the breakers read "NO"). Neither of these orientations correspond to what 408.43is referring to in the 2020 408.43 face up, which means such that the face of the panel faces the ceiling. It is allowed (provided you obey the 240.83 provisions) to mount them facing down (i.e. you screwed it to the ceiling).

 

[mwm1752]

I would tend to interpret face up would indicate the face/front of the panel being place to above the bottom of the panel. Therefore if you mounted the panel in a horizontal position the face/front could be on a vertical plane. This corresponds with 230.33 as long as they meet 230.81 standards

 

[pv_n00b]

The book, Analysis of Changes 2020 NEC has an interesting writeup on 408.43. It says that the intention of "face-up" is that the enclosed OCPD are facing upward. So 408.43 would allow a panelboard to be mounted face-down, but still horizontal. But it still seems like the two sections are opposing.
240.33: Enclosures for overcurrent devices shall be mounted in a vertical position. Circuit breaker enclosures shall be permitted to be installed horizontally where the circuit breaker is installed in accordance with 240.81.
408.43: Panelboards shall not be installed in the face-up position.

Circuit breaker enclosure is not defined in the NEC. So is the provision in 240.33 limited to circuit breaker enclosures that are not panelboards and what is a circuit breaker enclosure then? Does 240.33 have the be interpreted to mean circuit breaker enclosures can be mounted horizontally but not face-up?

 

[LarryFine]

Face-up panel installations are seen in laundromats, where each island has a sub-panel.

 

[mwm1752]

So if you face a panelboard towards the floor what breaker is made that complies with the “up” position of the handle shall be the “on” position. when the movement is movement of the switch is horizontal (side to side)& not vertical (up to down)?

 

[LarryFine]

So if you face a panelboard towards the floor what breaker is made that complies with the “up” position of the handle shall be the “on” position. when the movement is movement of the switch is horizontal (side to side)& not vertical (up to down)?

Virtually every branch-circuit breaker is operated horizontally. That's why 'on' and 'off' are labeled.