In which setting would a CAT III rated instrument be used?

A CAT III rated instrument is specifically designed for measurements on electrical distribution systems and industrial installations. This category is suitable for use in environments where equipment is connected to power distribution systems, which typically operate at higher voltages.

In the context of switchgear and polyphase motors, which are often found in commercial and industrial settings, a CAT III instrument can safely handle the transient overvoltages that occur during the operation of these devices. They are built to withstand and measure high-energy voltage spikes, making them appropriate for diagnosing and maintaining the performance of such equipment.

Using a CAT III instrument in other settings, such as telecommunications or residential electrical work, may not appropriately align with the instrument's specifications related to overvoltage categories. Furthermore, low-voltage battery systems generally require a different category of instrument, often a CAT II or similar, since they operate at much lower voltage levels where the risk of overvoltage is significantly reduced.