Is a differential probe more versatile than a regular passive probe?

Thread Starter

Mark Flint

Joined Jun 11, 2017
75
Can I do all the same things as a single passive probe with a differential probe (eg, by grounding one of the two probes), or is there some function you just can't do with a differential probe?
 
Last edited:

crutschow

Joined Mar 14, 2008
23,806
You can do that with a differential probe, and they are very handy when you are trying to view a signal with significant ground noise.
But differential probes generally have a more limited voltage and frequency range than passive probes.
 

Marc Sugrue

Joined Jan 19, 2018
62
Pretty much, the question will be regarding the expected level of performance for the price you want to pay.

A differential probe commonly usually uses isolation and my experience is to get a similar level of accuracy in the measurement you pay a significant amount more to do the same job as the measurement has to cross an isolation barrier (normally to interface to an earthed instrument). The isolation levels also introduces bandwidth restrictions for the measurement which again you can pay a LOT more for a better instrument. If you need high frequency measurment capability
 

Reloadron

Joined Jan 15, 2015
4,733
You may want to give ABCs of Probes by Tektronix a read as it explains probes in detail. There really is no one size fits all when choosing a scope probe for an application. Just for example I did quite a bit with 3 phase delta power mostly sub 2 Hz frequency so while I needed a high voltage about 500 VAC pk top pk I really had no need for high frequencies response but did need the higher voltage and differential input. High end quality differential active probes can also carry a hefty price tag well exceeding $1,000 USD per unit. Depends really on what you may or may not need for your applications.

Ron
 
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