new UL 508A KAIC ruling

[heaterguy]

Does someone on this board know about the newly effective KAIC rating of components inside of UL 508A panels?

Our problem is the unrated solid state relays are now only rated for 5 KAIC. Accordingly, the newly effective UL 508A rules imply 5 KAIC is the rating of the panel with these relays. Of course our customers need 10, 15, 22, 35, and 65 KAIC rated panels.

What's the solution to our problem?

TYIA,

Heaterguy

 

[LionelHutz]

Supplement SB basically describes how to figure the short circuit rating. Table SB4.2 can be used to get a higher fault rating out of a device. Basically, an example from table SB4.2 says that if you put 20A class CC fuses in front on your complete 5kA SS relay circuit (fuses and relay or complete circuit as you werer building it before to get 5kA) then you can say the whole circuit is 200kA rated. You're really limited at 5kA though.

If that doesn't work, then you need a SS relay listed with higher fault ratings. It could be a ss relay that provides a higher fault rating when protected by a manufacturer recommended means.