• Insulation resistance test, Break down detect function (BDD), Contact check function
• Output voltage: 25 V to 500 V, Setting resolution 1 V
• Break down detect (BDD) function detects miniscule internal short-circuits caused by contamination
• Contact check function to determine if the instrument has made proper contact with circuit under test
• Stable insulation resistance testing, even in noisy environments
• Current limit function, auto discharge function, measurement conditions memory function, comparator function, test time function, auto range function

Detect contamination that could cause defects. Improve battery cell productivity through high-speed testing.

To assure battery quality over the long term, it’s necessary to detect the causes of latent defects in testing processes on production lines. Minuscule insulation defects can eventually degrade battery service life and cause fires. The principal causes of insulation defects are contamination (with metallic matter) and minuscule scratches occurring in production processes.

Detecting minuscule insulation defects caused by contamination.

The BDD function is a proprietary testing function that can detect minuscule internal short-circuits caused by contamination (with metallic matter) at the stage before battery cells are filled with electrolyte. By identifying and eliminating defective parts at an early stage in the production process, the BDD function helps prevent the risk of hazards such as fires and accidents caused by heating after battery shipment. Eliminating latent accident causes such as these facilitates the production of batteries that resist degradation and function economically.

The BDD function is a detection method that combines analog circuitry (peak hold) with digital sampling (at 5 MS/s). It detects minuscule changes by monitoring the amount of change in voltage during charging and the amount of change in steady-state voltage and current after charging.

In this way, it resolves the issue of incomplete detection due to sampling timing and resolution, which affects waveform measurement using conventional oscilloscopes or recorders.

Hioki succeeded in significantly reducing the effects of external noise by drawing on insulation resistance tester measurement technology and design expertise cultivated over many years.

As a result, the BT5525 can perform stable, variation-free insulation resistance testing at a level of quality that lets it detect internal short-circuits caused by contamination.

The BT5525 provides a contact check function to determine whether the instrument has made proper contact with the circuit under testby measuring the capacitance between the measurement terminals (stray capacitance and the capacitance of the circuit under test).