Capacitance
Test current waveform
Typical values measured at a test frequency of 1kHz
Characteristics tests for Varistors are carried out by using 8/20㎲
test impulses Data such as the maximum clamping
voltage(Vc)and the transient peak current(Itm) are obtained by
using this impulse current
Rated peak transient current : itm
Maximum peak current through the varistor with line voltage
However, for the Vc characteristics of the Axial Package type a
10mA DC squarewave current is used to cary out the test.
applied.
The maximum peak current with in the varistor voltage change
ratio of ±10% with the standard 8/20㎲impulse current applied
two times at 5 minute interval.
Rated transient energy : Wtm
Maximum allowable energy for a single impulse of 2ms
square-wave current waveform with rated continuous voltage
applied. Maximum energy rating base on a shift of Vnom of
less than ±10% of initial value.
Rated RMS Voltage : Vacm
Maximum continuous sinusoidal RMS voltage at 50/60Hz which
may be applied.
Rated DC Voltage : Vdcm
Maximum continuous DC voltage which may be applied.
Pulse lifetime rating
This is expressed as the maximum allowable number of
Rated average power dissipation : Ptam
Maximum average power that can be applied within the
impulse currents applied.
specified ambient temperature.
8/20㎲ impulse current(or 2ms square wave) is applied at
prescribed interval.
This curve also provides for derating current as required with
repetitive pulsing.
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SAMWHA CAPACITOR Co., Ltd.
SAMWHA [ SAMWHA ELECTRIC ]
