This standard applies to varistors for surge protective applications on systems with dc to 420 Hz frequency and voltages equal to or less than 1000 V rms@ or 1200 V dc. This standard contains definitions@ service conditions and a series of test criteria for determining the electrical characteristics of these varistors. If the characteristics differ with the direction of conduction@ then the tests determine characteristics for both polarities. Arresters covered by ANSI/IEEE C62.1-1984 [1]1 are excluded from this standard. The tests in this standard are intended as design tests as defined in ANSI/IEEE Std 100-1984 [3] and provide a means of comparison among various surge-protective devices. Varistor surge-protective devices are used to provide transient overvoltage protection in electrical circuits. Varistors@ as defined in ANSI/IEEE Std 100-1984 [3]@ are devices exhibiting a nonlinear volt-ampere characteristic. More specifically@ this standard applies to such devices having a monotonic increase in voltage with increasing current flow. Because the impedance of the device decreases with increasing voltage@ it provides a relatively low impedance path for surge voltages and a relatively high impedance at normal system voltage@ before and after the occurrence of the surge. Test criteria and definitions in this standard provide a common engineering language beneficial to user and manufacturer of surge-protective varistor devices. Due to the voltage and energy levels employed in the majority of tests described herein@ all tests should be considered hazardous and appropriate caution should be taken in their performance. 1The numbers in brackets correspond to the standards listed in the Bibliography@ Section 7. of this standard.
IEEE C62.33-1982 history
2016IEEE C62.33-2016 Test Methods and Performance Values for Metal-Oxide Varistor Surge Protective Components
1982IEEE C62.33-1982 Standard Test Specifications for Varistor Surge-Protective Devices