Surge testing is a method that applies a sufficiently high impulse voltage (up to 6kV) with a very short duration (<160uS) to the devices under test (DUTs), which include lead-acid battery cells and metal film resistors.

When the switch is opened and an impulse test is applied to the lead-acid battery cell, the internal resonant inductance of the 19311 Series causes the cell to resonate with the resonant inductance and capacitance inside the 19311 Series, producing a resonant waveform. The peak voltage of this resonant waveform can be used to detect any abnormal voltage withstand capability in the battery cell. When the switch is turned off, the lead-acid battery cell only resonates with the internal resonant inductance of the 19311 Series. The decay of the peak voltage of this resonant waveform represents the insulation quality of the battery cell. By analyzing the tested resonant waveform and comparing it with the golden sample, it is possible to determine whether the lead-acid battery cell is a good product. Impulse testing of lead-acid battery cells that have not yet been injected with electrolyte is mainly used to check for insulation defects or missing separator before electrolyte injection.

Identifying insulation defects at the laser trimming areas of metal film resistors using AC/DC voltage can be challenging. Insufficiently high test voltage or excessive test power make it difficult to detecting metal particles in the laser trimming. Therefore, impulse testing is necessary to ensure the insulation quality of metal film resistors at these laser trimming areas. When the switch is turned on and an impulse test is applied to the metal film resistor, the internal resonant inductance of the 19311 Series generates a selfresonance. The resulting resonant waveform can be analyzed or compared with the golden sample to assess the insulation of the metal film resistor. After the switch is turned off, the difference in the decay of the resonant waveform's peak voltage represents the difference in resistance value of the metal film resistor, as it is connected in parallel with the resonant inductance. The impulse test on the metal film resistor is primarily carried out to detect insulation issues in the laser trimming areas inside the capped metal film resistor, bringing out the true characteristics of products with poor quality. By examining potential problems such as poor insulation quality and insufficient insulation distance in the laser trimming areas of the metal film, this testing technique ensures that the resistance of the metal film resistor does not change over time due to inadequate insulation quality or insufficient insulation distance caused by laser cutting. This reduces the chance of workplace accidents and ensures the reliability of electrical products for long-term use.