I'm looking at some clamp on current monitors such as this: https://www.robotshop.com/en/seeedstudio-non-invasive-ac-current-sensor-30a-max.html

It's rated for 30A max. What happens if you clamp it on a wire carrying more than 30A? Can it damage the circuitry inside the clamp? Or is it just a max of 30A of range - i.e. no matter how much more current you pass, the output maxes out at 1v.

Same question about these 5A boards made to interface to arduino: https://www.ebay.com/itm/Analog-Cur...ter-Sensor-Board-for-Arduino-NEW/264257181462

Thanks

 

In general, I would expect the output to start to saturate above its rated current, with the output voltage soft limiting.
It's not likely to cause any damage.

 

My experience with putting an inductive current pickup on a wire with more than the rated current is that the readings are not accurate. The magnetic part saturates and so the output voltage does not increase in a linear manner. The magnetic field continues to increase but that is the flux through the air, so the reading is way low. But no physical damage. That is not the case with series ammeter shunts, however. They are subject to overheating and solder melting and such nasty problems.

 

From Coilcraft.com This series flattens out at 450 to 500mV.

 

From Coilcraft.com This series flattens out at 450 to 500mV.
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Some are better than others, and a few are MUCH BETTER than others. Coilcraft is one of those.