IEEE 62.33-2016 pdf free
IEEE 62.33-2016 pdf free.IEEE Standard for Test Methods and Performance Values for Metal-Oxide Varistor Surge Protective Components.
The waveform of the impulses used in this standard shall meet the requirements ofAnnex D.
When tests are conducted, the MOVs of leaded disc type shall be mounted as for normal use, while the MOVs of surface mount device (SMD) types shall be mounted on the substrate. Unless otherwise specified, the substrate shall be as described in Annex A.
5. Electrical characteristics
5.1 General
MOVs of various types should have the characteristics listed in Table I when tested as specified.
For the tCsts for electrical characteristics, a statistically significant number of samples should be chosen. Generally, “statistically significant” is 30 samples. but guidance such as acceptable quality level (AQL)tablcs or customer requests may apply.
5.2 Varistor voltage
5.2.1 Preferred voltage values
Whcn tested according to 5.2.2, varlstor voltage should be within the specified limits. Table 2 and Table 3 show the nominal varistor voltages of high voltage and low voltage disc types that are commonly used; their allowable tolerances are ±10%. Components with voltages higher than Table 2 arc less commonly used and individual suppliers should be contacted to find the voltages available.
The nominal varistor voltages and tolerances listed in Table 4 are typical for SMI) types.
5.2.2 Test method
A power supply of constant current source of I mA dc ±10% shall be used. The voltage across the tested MOV should rise from a lower value than that of the varistor voltage measured, rather than declining from the maximum voltage of the current source. The ripple of dc voltage shall be no more than l% The time ofapplied test current 1 mA shall be within 20 ms to 100 ms prior to taking the voltage reading. The accuracy of the voltmeter shall be ±0.5%. The voltage shall be measured for positive and negative polarities of the test current.IEEE 62.33 pdf free download.
