Quote:
Originally Posted by Findm-Keepm
What is your rationale? I know theirs - to prevent the inductive load of the meter from becoming resonant - hence, they shunt it with a bypass cap to ground, effectively eliminating the possibility. My Save the Flyback tester has a .47uf/600V across the meter.
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Rationale for needing no cap would be- the actual DC resistance of the instrument (e.g. Simpson 260) is very low when measuring current. The higher the current range, the lower the resistance as lower and lower shunt values are switched in. The instrument is functionally a dead short when measuring current.
So having a cap across it is fine as a 'feel good' measure, but no actual need for it.
The movement is gonna 'see' raw, unfiltered spikey waveforms anyway when the instrument is measuring voltage, and is none the worse off for it.