Dielectric strength of plastics

This analysis (IEC EN 60243-1) determines the dielectric strength of solid plastics by subjecting a flat plate of the sample to a gradually increasing voltage between two electrodes. The voltage at which the plastic loses its insulating properties is known as the breakdown voltage. The dielectric strength is calculated by dividing the breakdown voltage by the thickness of the sample and is typically expressed in kilovolts per millimeter (kV/mm).

The samples are preconditioned at 23 °C and 50% RH for 24 hours before testing and are tested in a surrounding medium of thermostated insulating oil to prevent flashover.

The analysis includes five tests at 23 °C. The dielectric strength is determined from the median of the test results. Five additional tests will be made if any single test result deviates by more than 15% from the median. The dielectric strength is then determined from the median of the 10 results. These additional tests do not affect the price of the analysis.

Maximum dielectric strength 50 kV/mm. Analyses conducted at cryogenic and elevated temperatures (up to 250°C) are also available. Please contact our testing experts for a quote tailored to your project.