Some of the enclosure manufacturing company utilizes UL recognized material for their enclosures. To define it, the UL frame serve as the property of material used for enclosures. Needless to say, that the materials used for making enclosures are not the same in nature and it is the reason why it doesn’t not have the same rating. Any design engineers should be ready to recognize the differences in ratings to have a better understanding why the numbers must vary. To better explain this differences, let’s look at the following:
For UL rating, the UL-94 is the Standard for Safety of Flammability of Plastic Materials for Parts in Devices and Appliances testing. This can only mean that every product that has UL-94 rated material has been proven its flammability characteristics. This means that this material can be used for the suitability of the material in a given operation. Once the end unit is acceptable to be utilized for any type of product use, it should also undergo testing for that specific product. Ul-94 can determine how the material will react given the set of conditions but it cannot exactly pinpoint the exact characteristics of the components using the end product and just by relying on this rating.
With this in mind, there are two different testing methods: the horizontal and vertical. The HB rating means that the product was tested using the burn or HB test. The type of flame that was used and applied for this product testing was founded to burn more slowly compared given a specific amount of time. The time it takes for the flame to burn the product also depends on the thickness of the material.
The ratings that ends with V2,V2, or V0 only means that the quality of material was gaged and tested using the vertical position. The ratings also indicates that the tested material after it undergo certain testing eventually self-extinguished because of the removed burning source.