We manufacture a range of cable assemblies that require high voltage testing on our “hipot” tester.
FIRST, a quick explanation of “hipot”.
To “hipot test” a cable assembly means to apply a HIgh POTential between each wire and all other wires and shields to assure that they are properly insulated, or isolated from each other.
For cables that contain only wires and /or un-terminated points, this is a fairly simple task. But, if your cables have embedded components resistors, diodes, capacitors, coils, ICs etc. you run the risk of damaging these components by high voltage testing.
There are two elements of a high voltage test;
- A DWV dielectric withstand voltage test commonly done with AC voltage.
- A IR insulation resistance test always done with DC voltage.
For the purposes of this document “hipot” refers to both.
Why we can safely test assemblies with components on our Cirris Hipot tester without damaging the components.
Cirris testers do a low-voltage continuity scan first, before doing the high voltage test.
Cirris testers can selectively apply voltage on multiple test points at a time.
Since we know the exact wiring pattern of the cable BEFORE WE DO THE HIPOT TEST we just tested for continuity we can now intelligently apply high voltage so that we;
- Test each NET against every other NET that should be isolated from each other.
- Combine NETS that are “linked together” with components so that we do not allow a voltage drop across, or current through, the components.
What is a NET?
A NET is:
- Two points connected by a wire.
- A group of points connected by wires.
- A non connected NC point or points.
NC points, while not included in the NET List, are treated as separate nets for the hipot test since they must be checked for isolation from all other points/nets.
Jacarem is accredited to BS EN ISO 9001:2008 Quality Standard, and these practices are used throughout the production of every cable assembly being manufactured.
Does your company have a requirement for High Voltage Cable Assemblies? If so, please send your drawings / specifications to [email protected] or phone 01494 791336.