technically speaking

Can the hi-pot test and the insulation resistance test be combined into a single measurement? Let’s discuss each of these parameters as circuit parameters and as safety parameters.

For production-line testing, the 25- or 30-amp grounding continuity test is not likely to identify construction anomalies that would not also be identified by a simple low-current test.

High-current grounding impedance tests have been specified in safety standards for many years. There are two, independent sources for these tests.

There always seem to be questions about hi-pot testing. Maybe I can present some of those questions and their answers.

How does safety work? That is, given a hazardous situation, how do we prevent injury from that situation?

Did you ever wonder why we use 0.1 ohm (and sometimes 0.5 ohm) for the ground impedance value for plug-and-socket connected equipment?

Recently, a colleague remarked to me, “Philosophically, of course, there is no such thing as absolute safety.” Could this be true? Is there a situation where a man could not possibly injure himself?

This issue’s topic is rather unique because this column addresses safety requirements for a non-safety critical device, “operational” or “functional” insulation.

What is a “level of protection”? What are “measures of safety”? Why do they apply only to electric shock and not to other injuries?

Why? Why is it that one of the biggest aggravations in product safety is that of markings? For some reason, it seems that we can never get the markings right the first time. Furthermore, it seems that markings that have been acceptable for years will suddenly go bad.