Which Specs To Look For When Buying Differential Probe

[bostonman]

I'm looking to buy a differential probe and looking at a Micsig one but uncertain which specs are important.

I've seen a few models, one is 700V and another is 1300V. Most likely going with 1300V will provide better safety, but the attenuation is more (50x / 500x).

If I go with higher attenuation, this means I need to increase the scope V/div and may not see certain signals.

My guess is three main specs are important: voltage, rise time, and attenuation.

Is this correct or do other important specs matter too?

[PartialDischarge]

The specs that are important depend on the application of the tool

[bostonman]

True.... but for a universal diff probe that would be exclusive to AC circuits (and not exceeding 120) and non-grounded stuff.

I don't see a future need to worry about rise time on digital circuits since those are usually isolated through the power supply.

[jonpaul]

most important

CMRR common mode rejection ratio vs frequency
probes and connectors
power supply isolation
input protection

We used Yokogawa and Tektronix differential probes, but found these to be easy to damage physical or electronicly, and of very limited benefits


Jon

[bostonman]

Silly question, so if I go with the 1300V that is 50x / 500x attenuation, this means a 50v signal will look like 1V on the scope?

If this is the case, then simple digital signals (0-5v) will need a scope that can have plenty of amplitude.