Regarding UL Certification process

[Harsh]

Hello Everyone,

Can anyone provide the details regarding the essential requirements of the compliance of the subcomponents of the products if we want to opt for the UL registration? As per my research I have found that people mostly recommend to select the UL recognized electronics components.

Is it mandatory to use UL recognized components? & if not the non UL recognized components would increase the overall costing of UL certification by huge margin?

Also as the UL also conducts audits on a time to time basis then the use of non UL recognized components requires addon testing everytime? What about the requirements of Mechanical Components for UL Certification?

Thanks in Advance.

 

[CharlieUK]

If you want to have UL Listing for your end product, all "critical components" will need to be UL Recognised.

 

[Harsh]

Does that mean in case the critical components are not UL recognized then the lab will not proceed for testing before their replacement?

 

[CharlieUK]

It depends on the lab and what you have asked for - you don't need UL Recognised Components to comply with a UL standard, but you do to get the product listed.

 

[ISmith68]

Am I right in thinking that you can use a different certification mark, like ETL for sales in USA. In that case 'safety critical' parts that are not UL listed could be used, but would need to be verified once a year in the ETL lab, not cheap, but an alternative.

 

[Harsh]

Yeah that is possible. But in our case customer need UL only so in that case the same could be possible with UL also?

 

[CharlieUK]

UL don't accept component recognition from other NRTLs.

 

[Harsh]

Understood. But what I am trying to say is that if the critical components are not UL Recognized then UL can still perform testing on the product for its registration & year by year verify the non-recognized components with addon charges?

 

[CharlieUK]

No, UL will not accept Critical Components that aren't UL recognised for UL Listing.

 

[Jaydub]

It has been a few years since I dealt with this, but I believe If you have a critical component that is not UL recognized, UL can test that component to determine if it is acceptable. That would incur extra testing costs. You would then be required to use that exact component and not be able to substitute another equivalent part without retesting.

If you use UL recongnized components you may be able to substitute another UL recongnized component with the same ratings.

I worked on a product that had a custom power transformer. When we went through UL testing we had to submit several samples of the transformer including one unvarnished sample and complete drawings and specs. They tested the transformer and found it to be accepable in our application. That transformer was then called out in the follow-up procedure that was used by the field inspectors.