UL489 Vs Ul489B

[Carlos_]

Hi People,

I am designing a solar plant and the PV modules will be behind DC optimizers. I am trying to choose a CB however, I am not sure if I can use UL489 instead of UL489B rated CB. I believe that UL489 will be suitable as the surrent from the PV array will be regulated by the optimizer therefore, there will not be any sudden current spikes due to solar fluctuability.

I have not access to the UL489B standard so I am not sure if there is anything else I should consider.

Could anyone summarize the differences between the 2 standards or give their opinion if when using optimizers UL489 can be used?

Thanks!!

 

[FacEngrPE]

Molded-Case Circuit Breakers, Molded-Case Switches, and Circuit-Breaker Enclosures

https://standardscatalog.ul.com/ProductDetail.aspx?productId=UL489

Molded-Case Circuit Breakers, Molded-Case Switches, and Circuit-Breaker Enclosures for Use with Photovoltaic (PV) Systems

https://standardscatalog.ul.com/ProductDetail.aspx?productId=UL489B

UL now offers free digital view. You do need to register.

This document provides some clues when the UL489B product is likely to be required
Bussman Solar Circuit Protection Guide Similar application guidance is available from other suppliers of UL489B MCB's

 

[Carlos_]

AWESOME! I did not know UL allowed you to check that stds for FREE!
I have been saying this for YEARS! STDs should be FREE!