Measuring max Vrms and duration of a surge


I need to count surges, the max V of each surge, and the duration of the surge. I was hoping that there would be a (hopefully low cost) IC that can both suppress surges and do this analysis, or at the very least, expose interrupts on sag and spike. Does anything come to mind?

Thank you!


It’ll be necessary to define the source you’re monitoring, what constitutes a “surge”, and things of such nature.

There are a fair number of energy metering ICs available, which may offer functionality that you would find useful. At the other end, a person could also probably run things through a rectifier and some filters, fed the result into a comparator, and track the output of that. I’m not immediately aware however, of any devices which specifically are designed for the task described.

Regarding suppression, this is in most cases a separate function, due to the variability of application requirements and the typical need to use rather beefy components that do not lend themselves well to integration with IC silicon.

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Transient voltage surge measurement is one of the most difficult to make. Normally it requires instrumentation costing thousands of dollars to get even medium accuracy transient voltage measurements. Instrumentation for high accuracy transient measurement runs from 10k to 200k US dollars.

This quote from Fluke gives a little taste of the complexity to think about:

A transient voltage is a temporary unwanted voltage in an electrical circuit that range from a few volts to several thousand volts and last micro seconds up to a few milliseconds.

What are voltage dips, swells and transients? | Fluke (they recommend one of their $10K instruments)

This application report from TI has some practical information on doing it with an oscilloscope ion a very application specific way.

What you may be able to do is define a very narrow range of voltages and times and engineer a custom circuit that gives a rough indication of the surge parameters.

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