Products > Test Equipment
Keysight's new 34465A (6.5 digit) and 34470A (7.5 digit) bench multimeters
Dr. Frank:
--- Quote from: Alex Nikitin on October 25, 2016, 04:29:48 pm ---
Hi Frank,
.. . May I use your graph in my correspondence with Keysight as an example of a healthy 34465A readings?
Cheers
Alex
--- End quote ---
Of course.
Arguing with the RMS noise is quite difficult with Keysight, as everything is inside specification, even your fluctuating measurements.
Therefore, a comparison like this is good, better if you really find an issue like an unstable current source (check also other ranges), or a bad switch.
I can't complain about KS, they reacted very quickly to my findings about the 100V/1kV range errors, and even replaced the instrument for analysis.
In my case, these errors were also inside specification. James Durr did a great job.
Frank
saturnin:
@Alex
Aha, I see now ... but if I read the table correctly 1 ppm noise adder value refers to NPLC=1. It is 0 ppm for NPLC=100. (Do they really mean that there is 0 ppm noise with NPLC=100?)
As Dr. Frank wrote, 25 ppm variations you observe do not violate +/-25 ppm 24hour specs, so I think the only change is to blame ohm noise performance of your unit...
Have you measured what the short-term rms noise (sdev) of your unit is?
Alex Nikitin:
--- Quote from: Dr. Frank on October 25, 2016, 07:26:52 pm ---
--- Quote from: Alex Nikitin on October 25, 2016, 04:29:48 pm ---
Hi Frank,
.. . May I use your graph in my correspondence with Keysight as an example of a healthy 34465A readings?
Cheers
Alex
--- End quote ---
Of course.
Arguing with the RMS noise is quite difficult with Keysight, as everything is inside specification, even your fluctuating measurements.
Therefore, a comparison like this is good, better if you really find an issue like an unstable current source (check also other ranges), or a bad switch.
I can't complain about KS, they reacted very quickly to my findings about the 100V/1kV range errors, and even replaced the instrument for analysis.
In my case, these errors were also inside specification. James Durr did a great job.
Frank
--- End quote ---
Thank you.
--- Quote from: saturnin on October 25, 2016, 07:37:58 pm ---@Alex
Aha, I see now ... but if I read the table correctly 1 ppm noise adder value refers to NPLC=1. It is 0 ppm for NPLC=100. (Do they really mean that there is 0 ppm noise with NPLC=100?)
As Dr. Frank wrote, 25 ppm variations you observe do not violate +/-25 ppm 24hour specs, so I think the only change is to blame ohm noise performance of your unit...
Have you measured what the short-term rms noise (sdev) of your unit is?
--- End quote ---
I read this "0" RMS noise value as <1ppm. Which is confirmed by Dr. Frank's results (sdev = 0.16ppm) .
Cheers
Alex
Alex Nikitin:
--- Quote from: Dr. Frank on October 25, 2016, 07:26:52 pm ---
Arguing with the RMS noise is quite difficult with Keysight, as everything is inside specification, even your fluctuating measurements.
Therefore, a comparison like this is good, better if you really find an issue like an unstable current source (check also other ranges), or a bad switch.
--- End quote ---
Hi Frank,
Thank you, your graph and some additional information from me did convince Keysight and I'll get a replacement meter from Farnell sometime soon tomorrow. I've tried rear terminals and other resistance ranges today and get roughly the same "jumpy" results. Here is the graph from real terminals for 2.5 hours. Let's hope the replacement would be OK.
Cheers
Alex
Dr. Frank:
--- Quote from: Alex Nikitin on October 26, 2016, 10:52:13 am ---
Hi Frank,
Thank you, your graph and some additional information from me did convince Keysight and I'll get a replacement meter from Farnell sometime soon tomorrow. I've tried rear terminals and other resistance ranges today and get roughly the same "jumpy" results. Here is the graph from real terminals for 2.5 hours. Let's hope the replacement would be OK.
Cheers
Alex
--- End quote ---
;D ;D ;D ;D
are you able to measure the current source in 4W mode? I'd be interested in this failure mode, as KS probably won't give a feedback.
Also, please save the serial number, so that you can see in a few weeks, whether your unit had been refurbished..
The replacement for sure will be as good as mine 8) 8) 8)
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version