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Technical System Catalogue RiLine60

Information on UL (Underwriters Laboratories) Information on UL UL or Underwriters Laboratories was founded in 1894 as a subsidiaries worldwide, with an emphasis on product testing non-profit-making organisation for testing and certification. aimed at general safety. UL operates five testing laboratories in the United States and Why are UL approvals important? International regulations and standards such as NEMA For many applications, the sole use of UL and/or CSA- and IEC are used as a basis by manufacturers for product approved products is a requirement; consequently, it is developments and subsequent testing. advisable to design electrical controllers for North Ameri- Nationally recognised test laboratories confirm and certify can applications with suitable UL-approved components. that a product complies with the specific standards; in North America this is carried out by organisations such as UL or CSA (Canadian Standards Association). How does the US system for electrical safety work? Every piece of electrical equipment (machine/plant) is tested use of UL-recognized or UL-listed components an important by the competent local inspector (AHJ = Authority Having indication that a system complies with the safety require- Jurisdiction) prior to commissioning. The AHJ has the final ments to NFPA 70. This saves time and money during con- say with regard to commissioning. All AHJs use Standard struction and commissioning of the equipment, as the UL NFPA 70 (NFPA = National Fire Protection Association) as a symbol indicates that testing of the components and/or of basis, which is generally regarded as the NEC (National the system did not reveal any foreseeable risks with regard Electrical Code). NFPA 70 is therefore an important basis for to fire, electric shock and associated dangers. UL 508A (Industrial Control Panels). The AHJ considers the The UL symbols: “UL listed” or “UL recognized” When labelling UL-approved products, a general distinction is made between Recognized Components and Listed Devices: 1 (Recognized Components) 2 (Listed Devices) This label is used on products which are not complete Here, it is only important to note that the remarks and in terms of their application. These products are listed rating data specified on the product are observed with in the UL’s “yellow component database”. The correct use the application. Terminals for field-wiring are authorised of such components must make due allowance for the as Listed Devices (see “Important remarks”, point 3, “Conditions of Acceptability”, listing the framework condi- page 18). tions and application parameters approved by the UL. 1 2 Recognized Component Listed Device Sample rating plate for busbar support with . Sample rating plate for busbar support with . 2- 17 Technical System Catalogue/Power distribution


Technical System Catalogue RiLine60
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