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Electronics => Projects, Designs, and Technical Stuff => Topic started by: eponte5 on March 15, 2016, 04:09:18 pm

Title: Voltage rating on scope
Post by: eponte5 on March 15, 2016, 04:09:18 pm

I have a Rigol DS1062CD that shows on the BNC "all inputs 400V Max"

I'm pretty certain that if I use a differential probe like the one Dave sells in his Amazon store, (B&K Precision PR-60 Active Differential Probe)  which the data sheet states 700V max, I'd be ok to use it on my scope since it's an isolation probe.

My question is what about a X100 scope probe that says it's safe for 2000V max.  Because its directly connect to my scope without isolation should I still only use it to 400V Max?

The conservative/safety conscience me says 400V max.

I don't have at this moment a voltage higher then 400V to measure, but if it where to come up, I don't know if I could use the X100 times probe on it or go with a differential probe.

Thanks in advance.

Title: Re: Voltage rating on scope
Post by: klr5205 on March 15, 2016, 04:19:29 pm

Check out page 42 of this document from Tektronix: http://circuitslab.case.edu/manuals/Probe_Fundamentals-_Tektronix.pdf (http://circuitslab.case.edu/manuals/Probe_Fundamentals-_Tektronix.pdf)

Title: Re: Voltage rating on scope
Post by: Fungus on March 15, 2016, 06:35:49 pm

Quote from: eponte5 on March 15, 2016, 04:09:18 pm

My question is what about a X100 scope probe that says it's safe for 2000V max.  Because its directly connect to my scope without isolation should I still only use it to 400V Max?

Assuming it's from a reputable source: You can use it for 2000V.

Because the probe attenuates by a factor of 100 the oscilloscope will only see 20V. That's well inside the 400V rating so it's safe to do that.

OTOH be very careful - you're poking bits of metal at a 2000V source. Observe general electrical safety precautions.