Insights into the Applications of Cable Testing

Ensuring compliance with various electrical safety standards and confirming that the assembled product is free from electrical or mechanical defects are critical aspects of hipot testing.

Image Credit: Vitrek, LLC

Hipot testers are used to measure the leakage current and insulation resistance between all components and connections, verify solid ground connections, and test ground bonds.

These tests include the sequential application of high voltages or currents between pairs of components under precision control, followed by exact measurement and result recording. The industry offers exceptional electrical safety testers like the Vitrek 95x and V7x series.

Multiple measurements are often necessary for many Hipot tests. For example, a three-conductor power cord linked to an electronic component must pass both a voltage withstand test and a ground bond test between the ground wires and the chassis.

For a connector assembly with multiple pins, a distinct test would be necessary for each pair of contacts, between each contact and adjacent wires, and subsequently, the connector body. Similarly, a basic four-conductor cable may necessitate 20 individual tests:

1. Continuity on each conductor (2 or 4 conductor)
2. Insulation resistance between each conductor and ground or shell (four more tests)
3. Insulation resistance from each conductor to all the other conductors (12 additional tests)

In the case of a 24-conductor cable, the total number of individual tests required could reach as high as 578. Manual testing for such an extensive number of tests is not only laborious but also prone to errors:

• Were all of the combinations tested?
• Were some inadvertently duplicated?
• Have all the test conditions been implemented?
• Did the operator correctly record the data?

To avoid manual testing challenges, a programmable, multi-point switching system is often a crucial tool to efficiently and precisely implement the complete series of electrical safety tests.

Using a fixture to quickly connect the entire assembly, a multi-point switching device interfaces with the hipot tester and automatically sequences the testing through all possible combinations. Despite sounding "simple," these devices require significant engineering and innovation.

This information has been sourced, reviewed and adapted from materials provided by Vitrek, LLC.

For more information on this source, please visit Vitrek, LLC.