High Voltage Test

While during an open test (connection test, continuity test) the availability of a nominal connection between two test points should be validated, a high voltage test verifies if the insulation of this connection meets the requirements. Before, often a short test (low voltage test) is performed to detect a possible unwanted direct connection in order to avoid any further damage to the unit under test (UUT). A high voltage test is often part of a cable test in addition to the open test and short test.

There are three types of high voltage tests:

• The breakdown test determines the voltage value, from when the insulation of a cable or a component is not sufficient anymore and an arc ignites (destroying test method).
• The electric strength test validates if the insulation of a cable or a component resist a certain, programmed voltage (qualitative)—mostly by using AC voltage (see HV-AC test).
• The insulation resistance test (insulation test) determines through multiple measurement methods the insulation resistance between two measurement points (quantitative)—mostly by using DC voltage (see HV-DC test)

To perform these tests to detect the risk for a breakdown, the electric strength and the isolation resistance, the test systems needs special generators that are able to provide high voltages.

In this category of testers, the compliance with specific security standards is absolutely mandatory. In WEETECH systems, the security circuit will be interrupted in case of any danger and with this, the generator supplying the high voltage will be switched off.

In case a manufacturer has been certified according to ISO 9001, the test results must often be logged for retracing issues and stored in a database for further analyzation in statistics.