Infrared Windows and UL Ratings
We are often asked the question " What happens to my UL Rating when I install Infrared Windows."
If the panel that you intend to fit the IR window into carries any certification marks, these should, where reasonably practicable, not be breached in any way. In the case of a panel with UL certification, you should only consider using UL recognized components. A question that is regularly asked is, How does field installation of IR windows affect the UL status of the panel?
The component (in this case, the IR window) can be field or factory installed. The issue is the listing of the product in the field to which it is installed. Installing this product in the field does not negate the listing mark. Customers often modify assemblies that are UL listed and marked. Any modification done in the field is not covered by an existing UL mark. Therefore, UL is not responsible for the certification of these listings.
When changes are made to listed assemblies that affect the rating of the equipment, UL will do a field inspection of the modified product to re-certify the equipment meets UL requirements. A customer may request this to be done. The IR window would have to be added to the UL procedure for that piece of equipment. If it is not covered in the UL procedure, then UL could not re-certify.
In cases where the IR window is not part of a product’s UL listing, there is another option, the field evaluation by UL. Since the IR window is a UL recognized component, UL should be able to provide a UL mark that would verify the modified product had been evaluated. However, this would probably not be required in most cases.
Even though IRISS products are UL Recognized and would have been installed properly as per the manufacturer’s instructions (which also are approved by UL during the testing of the products, etc…) you will still need to get UL to conduct a field evaluation to approve the modifications. I would however ask what the companies mandates are for any other modifications before calling in UL, i.e.:
1. If the company changes a breaker or modifies a cabinet by taking new feeder cables to another MCC (which requires punching a hole in the steel cabinet, and placing a cable gland/ critter guard around it would they call in UL to verify the modification?
2. If they had to replace an amp meter and the old one was no longer available.. the replacement is approximately 50% larger so they need to enlarge the hole to accept the replacement unit… would they call in UL to verify the modification??
The reason I ask these questions is primarily due to the fact that companies modify switchgear (like the two tasks listed above) continuously, however they never give a consideration for recertifying the UL listing! It’s just that IR windows are alien to so many people and as such they are ultra cautious (as they should be… electrical safety is not something anyone takes lightly). So I always ask what is the company’s position on this type of modification and suggest that they treat IR window installations the same… (so long as they are recognized and tested to the required standards of course).