Current clamp difference question...

Not sure...But I suspect capacitance somewhere.

D from BC British Columbia Canada

"Default User"

The AC clamp has significant variations in its current sensitivity that depend on frequency - ie it has a response that falls away at low and high frequencies.

OTOH, the Hall Effect clamp has response that does not fall away low frequencies, but only at some fairly high one.

Where there are response changes with frequency - there are also phase changes with frequency ( all-pass filters notwithstanding).

So, the slanting ( aka tilt ) you see on the scope trace is the result of phase shift ( generated in the AC clamp) between the frequency components of that bi-polar pulse waveform.

..... Phil

Hi Phil,

Thanks for explaining it!!! That makes perfect sense!!

Alan

Depends on the low frequency bandwidth of the sensor, and the frequency of the current waveform. A transformer has a low-frequency limit that produces an L/R time constant for waveform droop. Gives the same effect as a capacitively-coupled RC time constant.

Commercial line frequency current transformers can be very droopy, particularly clamp-on types with their mechanically-forced gap (~reduces L); judging from the additionally poor HF definition, that could be what you're dealing with here.

RL

It looks like decay of voltage across a coupling cap.

The difference is the DC response of the HE clamp mandates no coupling cap.

See above.

Looks like a diode bridge fed into a storage capacitor with a switching power supply typical current waveform.