UL Listed

The "UL Listed" mark indicates whether a product has been tested by UL in accordance with nationally recognized safety and sustainability standards.
Cables for applications that can be fully described in a standard are certified as "UL Listed". A cable for connection of a washing machine to the power supply is an example of this. Its use can be clearly described. A normative description of the cable's use and the associated test set-up can therefore be clearly defined. The cable is to be manufactured, tested and marked according to "UL Listed" requirements. In the USA, it is not permissible to use a different kind of cable for such a clearly described application.

Plant manufacturers who export automation solutions to North America are often familiar with UL approval: the abbreviation stands for Underwriters Laboratories (UL) and is the most well-known and widely accepted testing organisation in the USA. The UL's set of rules is complex and has differences worth knowing.

Approval guidelines and certification processes vary in complexity depending on the market and country. For this reason, the Canadian organisation CSA and the US institution UL have signed a "Memorandum of Understanding": machine builders and component suppliers thus benefit from the recognition of tests, inspections and UL/CSA Listed or UL/CSA recognized certificates in both countries. This means that companies with UL approval can also export to Canada and companies whose products have CSA approval can easily get through customs and commissioning in the USA.

Both countries follow the same high safety standards. This white paper presents the approval types "UL Listed" and "UL Recognized", discusses the relevant differences and explains why plant manufacturers with a certificate from Underwriters Laboratories also succeed in importing into Canada.