{"id":70880,"date":"2021-10-29T07:36:31","date_gmt":"2021-10-29T07:36:31","guid":{"rendered":"https:\/\/www.dewetron.com\/news\/measurement-categories\/"},"modified":"2026-09-20T02:20:34","modified_gmt":"2026-09-20T02:20:34","slug":"measurement-categories","status":"publish","type":"post","link":"https:\/\/www.dewetron.com\/us\/news\/measurement-categories\/","title":{"rendered":"Measurement categories (CAT classification)"},"content":{"rendered":"
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Transient stresses and their implications<\/h2>\n
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Lightning strikes, electrostatic discharges or oscillations of electronic components are events that occur frequently in practice. Under certain circumstances, they lead to very high voltage peaks in the circuit – so-called transient stresses. Even if these transient stresses often last less than a fraction of a second, they can cause a lot of damage. Devices may stop working if they are not capable of handling such high voltage peaks.<\/p>\n

This fact was painfully apparent in the early days of electric rail transport. When people tried to measure the supply voltage of passenger trains back at that time, most measuring devices gave up their ghost after some time. This was due to the fact that passenger trains can generate high voltage peaks during initial acceleration and braking. The measuring devices were not designed for these kinds of transient stresses and got destroyed.<\/p>\n

But it is not always just the risk of broken measuring devices.\u00a0 Events such as lightning strikes may also cause physical injury. For example, if you measure the current in a fuse box during a lightning bolt, the risk of injury is high.<\/p>\n

To cope with this, it is important to know the limits of the measuring equipment used. One should therefore always ask oneself: “Can my measuring device withstand the maximum expected voltage peak?”.\u00a0 If this is not the case, you should use a different measuring device for the sake of your own health.<\/p>\n\n <\/div>\n <\/div>\n <\/div>\n <\/div>\n<\/div>\n\n\n

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CAT measurement categories<\/h2>\n
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Nevertheless, how well a device protects (the user and itself) against transient stresses, is often difficult to read of from data sheets. So-called CAT measurement categories make these properties easier to spot. They indicate in a simple way, if a measuring device works safely under certain conditions. The measurement categories primarily refer to the use in households, but they are also applicable way beyond that. According to IEC 61010-2-030, the following definitions apply:<\/p>\n