Safety Certification Standards and Safe Usage of Digital Multimeters
When you see symbols like UL, CSA, TUV, or read phrases like 'Design to meet...', you often think of independent testing and certification agencies. How can you prove that your digital multimeter meets the safety standards and definitions of CAtiII or CATII? It is highly likely that the manufacturer believes their watch meets CATIA II or CATIA I standards, but has not undergone any independent certification. The International Electrotechnical Commission (IEC) only develops and recommends its standards, but is not responsible for enforcing them. Only when a product has been tested and fully meets the standards of an independent verification organization, can the marks of verification organizations such as UL, CSA, TUV, etc. be marked on the instrument. In the mixed market of instruments, independent testing and certification may not be the best, but it may be the most direct method of identification.
To safely use a digital multimeter, the first step is to choose a digital multimeter that is suitable for the application and meets the application environment. Once you have selected the appropriate digital multimeter, you should use it according to normal application procedures. The International Electrotechnical Association has developed new standards for working in the power system. Confirm that the digital multimeter you are using meets IEC standards and its rated voltage meets the requirements for on-site applications. For example, if measuring a 480V power panel, your digital multimeter must meet the CATIII/600V standard, which means that the input circuit of this meter is designed to withstand transients in this application environment without harming the user. Choosing a digital multimeter labeled with UL, CSA, CDE, TUV means that this meter not only meets IEC standards, but also undergoes independent certification testing and meets the standards of independent testing agencies.
