Re: Measuring inrush current


 

Some transient measurements with my balky old 564 storage scope - just added to an album.
The first peak (measured at the transformer secondary = bridge rectifier input) as the capacitor charges is 560 amps. That should be within Ifsm specs for an alleged 200 amp bridge but I don't have any spec sheet (would also like to know the Ifrm).
I am somewhat alarmed to note that when the inverter starts up (420 amps DC inrush), for the first 1.0 second the transducer is maxed out, and it can indicate up to 700 amps... I may have to find a BIG 50 mv shunt and a differential probe if I want to know the true magnitude. But I have started it dozens of times already and so far the bridge is holding up! If it blows up I'll get a bigger one :)
Line current inrush appears to be reasonable for the size of this supply, and is within the capabilities of the circuit breakers.

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