srschang wrote:
I inrush current the same as surge capacity?
They're very different.
Time parameters for so-called "surge" current (or capacity) varies significantly from manufacturer to manufacturer. Sometimes it can be a fraction of a second---sometimes up to 30 minutes. Often times they don't even specify. Testing is not standardized. For many devices, it's basically a glorified continuous current rating---more a marketing ploy than anything else.
Inrush current approaches a second in time/duration and can be 2 to 6 times higher than the continuous current rating of the device. Inrush current is a quick, significant burst of current necessary to start inductive devices like an a/c compressor or motor. It takes an inrush current capable AC clamp-on ammeter to measure inrush current. It cannot be measured with a standard AC clamp-on ammeter.
A device can have an excellent, so-called, "surge" capability and a terrible inrush current capability. They're very different capabilities and ratings.
