i see many board have a mark, read "94V-0". what is this mean?

uhm.. one again... a mark that is reversed version of "LR", is this vendor name/what?

Posted on 2003-07-07 07:00:02 by dion
Posted on 2003-07-07 16:46:23 by Pone
what is UL rating? Ultra Low? or? still dont understand what they mean. is it somekind like isolator standard measurement value?

hmm... a standard/a class of what? concern with termal or insulation?

Posted on 2003-07-09 05:59:40 by dion
Hi, dion,

UL stands for Underwriters Laboratories. It is a US safety agency. They ensure products that are put on the market are safe to use, do not pose a safety hazard (such as electric shock hazard, fire hazard, etc). Any product that bears the UL mark has been recognized (meaning approved, but recognized is the terminology UL uses) by this agency. That means it passed some tests designed to prove the product is safe.

As for the markings on the PCB's, UL94V-0, they mean the PCB conforms to UL standard number 94, having a rating of 0. This standard deals with flammability. The rating tells you how good a board is, that is how flammable it is. The rating 0 is the best.

The reversed "RL" is the agency's logo. It can only be affixed to products recognized by UL.
Posted on 2003-07-09 11:50:04 by VVV
thanks again VVV, got it :)
Posted on 2003-07-10 05:49:42 by dion