Reply To: Focus Fusion Rail Gun

[asymmetric_implosion]

A rogowski coil is a magnetic coil. It is used to measure the time derivative of the magnetic field and converts it to a voltage. When placed around the anode, the rogowski coil is related to the current in the anode.

My observation on previous PF devices is the rogowski coil is a pretty clean signal when properly shielded outside the detection region. High voltage probes are more problematic. Most HV probes require a local ground in addition to the digitizer ground. The local ground is really the problem. A few volts of noise on the ground can lead to artificial signal at the digitizer by affecting the ground rather than the primary signal you wish to measure. I’ve notice noised coming into the system when the HV probe is not attached. Depending upon the location of the probe the noise can vary greatly. Large PF systems have a harder time keeping the ground lead short so they tend to produce noisier HV probe signals. When the ground lead is very short the noise is minimized and the best measurement is realized.