NEMA 4X

[Mehdi]

What if we add NEAM 1 rated component in NEMA 4X panel? is it going to be still NEMA 4X or downgrade? Thank you.

 

[petersonra]

What if we add NEAM 1 rated component in NEMA 4X panel? is it going to be still NEMA 4X or downgrade? Thank you.

NEMA enclosure type ratings are kind of meaningless, so it probably does not matter.

If you have a UL type 4X enclosure and you want to use it in a UL 508a control panel, any opening you make in the enclosure has to be listed to the same rating as the enclosure or you have to downgrade the enclosure rating.

But this does not really matter much if it is not a UL508a situation.

 

[Macbeth]

The Nema panel gets downgraded to the Lowest Rating.
When a "UL Type" rating is used UL508a will allow the use to Table 19.2 to downgrade the rating enclosure rating to something different.
Example
Type 4x Enclosure with Type 12 component make a Type 1 rating
Type 2 Enclosure with Type 12 component make a Type 2 rating

 

[don_resqcapt19]

Are you making a penetration to the NEMA 4X panel or just completely installing a NEMA 1 device or item inside the NEMA 4X enclosure?

 

[Mehdi]

Are you making a penetration to the NEMA 4X panel or just completely installing a NEMA 1 device or item inside the NEMA 4X enclosure?

I am working on UL508a Control panel, I have NEMA 4X Enclosure and a NEMA 1 din rail mounted VFD. So, I am trying to learn if we can add different Ul rated components inside the 4X enclosure without penetration. I know penetrated devices must be NEMA 4X, like push buttons, HMI screen, etc.

 

[jim dungar]

Inside devices can have any Type rating you want. Most of them are probably 'open style' even though the completed panel is 4X.

 

[Mehdi]

Inside devices can have any Type rating you want. Most of them are probably 'open style' even though the completed panel is 4X.

Thank you.

 

[Jraef]

But now that you provide the details…

Type 4X means the enclosure is SEALED to a level that prevents hose directed water, 60PSI from a 1 inch nozzle, from entering the enclosure. That will ALSO mean that heated air cannot ESCAPE the panel. VFDs produce heat, roughly 3-4% of their rated watts. So with no ventilation, they will cook themselves in a 4X box.

You can, in theory, over size the box and assuming the environment is not itself hot, allow the trapped heat to dissipate through the surface area of the exposed sides (meaning those not up against the floor or wall), but my experience is that the 4X box becomes so large and expensive, that it might be cheaper to just move the VFD out of the wash down area. The only other alternative is to add a Type 4X rated air conditioner, which is also expensive, large and requires maintenance.

 

[Mehdi]

But now that you provide the details…

Type 4X means the enclosure is SEALED to a level that prevents hose directed water, 60PSI from a 1 inch nozzle, from entering the enclosure. That will ALSO mean that heated air cannot ESCAPE the panel. VFDs produce heat, roughly 3-4% of their rated watts. So with no ventilation, they will cook themselves in a 4X box.

You can, in theory, over size the box and assuming the environment is not itself hot, allow the trapped heat to dissipate through the surface area of the exposed sides (meaning those not up against the floor or wall), but my experience is that the 4X box becomes so large and expensive, that it might be cheaper to just move the VFD out of the wash down area. The only other alternative is to add a Type 4X rated air conditioner, which is also expensive, large and requires maintenance.

Thanks Jraef for the detail explanation.