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In general, when we discuss the frequency limitations of signal measurement equipment, is it the actual frequency that matters or the voltage change per unit time (dv/dt).?
For example, the P6015A instruction manual states that the rated voltage is 20kv unless the frequency exceeds 460kHz. (from page 1-11 and 1-12). The maximum dv/dt at 20kv and 460kHz is 9.2E+9 v/s. From my basic understanding, as long as you do not exceed this dv/dt, there will be no problems. We are measuring the sparking voltage of an automobile ignition system and the impulse can have a maximum of 40kv, but the dv/dt is around 8.05E+8 v/s, which is less than the maximum of 9.2E+9 v/s. So this is acceptable, correct?
My question also extends to a more general realm. Will the measurement of a single event impulse that has a certain dv/dt be affected the same way as a sine wave that has a peak and frequency to produce the same dv/dt? (When I say affected, I mean affected by factors in the measurement circuit, say impedance, probe calibration, etc.)
Thanks in advance for any help.
For your second question, if you are dealing with a non-sinusoidal signal then there is going to be frequency content in addition to just that of the sine wave with a frequency causing the maximum dv/dt to match that of the pulse. Each piece of this content will behave differently. For example, if you look at a square wave on a scope, you will notice that the corners of the square wave are rounded off, and the lower the bandwidth of the scope, the more they will be rounded.
Just to make sure I do, please allow me to try out a hypothetical situation. Let's say I have a piece of equipment that says you cannot exceed a 500kHz frequency at 100v. This creates maximum dv/dt of 50x10^6 v/s. If I am using this equipment to measure an impulse, I will be ok as long as my impulse does not exceed 50x10^6 v/s, correct?
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