NEC 409.22 & 409.110 Approved Methods

[schmittg47]

NEC 409.110 (4) (b) states that "Short-circuit current rating established utilizing an approved method."

What are all the approved methods to calculate this? Specifically, there is an IEC 60439 or new IEC 61439 international standard. Can assemblies / compenents tested and approved per these standards be utilized in the USA?

 

[LEO2854]

NEC 409.110 (4) (b) states that "Short-circuit current rating established utilizing an approved method."

What are all the approved methods to calculate this? Specifically, there is an IEC 60439 or new IEC 61439 international standard. Can assemblies / compenents tested and approved per these standards be utilized in the USA?

If they have a UL Listing yes..

Welcome to the forum.:thumbsup:

 

[schmittg47]

Thanks for the prompt repsonse, but just to confirm. If the part is UL listed, I can use the published SCCR rating based on the IEC 60439 standard?

Can you tell me if this is published in the code, white paper, or common knowledge? My customer would like me to confirm the source?

Thanks again

 

[LEO2854]

Thanks for the prompt repsonse, but just to confirm. If the part is UL listed, I can use the published SCCR rating based on the IEC 60439 standard?

Can you tell me if this is published in the code, white paper, or common knowledge? My customer would like me to confirm the source?

Thanks again

look at 409.110 (4) b the informational note.

It tells you the UL standard ,,,you will need to look that up and read it.

 

[jim dungar]

If they have a UL Listing yes..

Testing and listing is not required by 409.110(4)(b). It only requires approval of the calculation method.

While there may be several methods availble for determining the SCCR of equipment, it seems the most popular is 'a supplement' of UL 508A.

There are minor differences between the Us and the IEC mtheods for determing available fault currents and device ratings. In general it is not good practice to mix the results of these methods: do not use IEC ratings with US available fault currents.