UL Marking

The Underwriters Laboratories (UL) is an organization founded in the USA in 1894 for testing and certifying products and their safety (similar to VDE, TÜV ...)

Several signs with UL or mirrored UR can be found on many many products and their components, especially with electrotechnical products.

Examples:

UL Listed sign	UL Recognized sign	UL Recognized sign for USA and Canada	UL Listed sign with reference to the product category

UL certification usually is required for market entrance in the USA. UL certificates are given for a special product and conformity is checked continuously. Not only is the end product checked but the manufacturing is as well.

Servo amplifiers and servomotors belong to the product category "Industrial Control Equipment". The UL sign on the products are always combined with the UL File Number (E Number, e.g.. E217428 for our servo amplifiers or E224106 for DBL/DBK servomotors). With this number the product can be found in the  Online Database of the Underwriter Laboratories.

An important competitor for UL is the CSA certificate, which also exists in a US version (CSA-US). The European authorities usually accepts UL standards, UL however usually does not accept EN standards.