It is defined as applied voltage that the current 1mA/cm2 flows MLV internally. For the Zinc oxide varistors, the breakdown voltage is related to the microstructure grain size mainly, not change by the variety and composition of the additives.
It’s Nonlinear Exponent to determine MLV characteristic. This value is related to the MLV construction and additives and can calculate by formula,α = log ( I1 / I2 ) / log ( V1 / V2 )
Under normal working status of the device, there is only small current flowing through the device, generally only a few μA. So called normal working status, it refers to a device in the normal operating voltage (Working Voltage), that is, the device is in a pre-breakdown status, the resistance values is very high, considered as an insulator, and only a tiny current flows. Generally, the measurement of leakage current is at 80% of breakdown voltage.
Max Clamping Voltage:
Maximum clamping voltage at specific current, usually, the max. pulse current of a specific current 10000 times.
Max Peak Current:
The major function of MLV is absorption of the overvoltage current, so the peak current of MLV is one of characteristics. Also the test will affect the product lifetime and with the largest surge current in reverse ratio. General test method is 8/20 μS and 10/1000 μS.
Max Energy Absorption:
When the surge strikes, the breakdown of MLV is in operation status. That would be a large current flow through the body, the surge energy is absorbed by MLV. However, the absorbing of MLV is limited. It’s measurement by formula, such as a peak current measured at standard pulse current by formula