Since the heatwave has passed, I did another run with the same meters. As before, I logged for two hours, but only pay attention to the second because the meters aren't really stable during the first hour even though I warm everything up half an hour prior to starting.
All logging at 100 NPLC as before. Data files will be uploaded to the xdev's share.
34401AAverage | 10.00027 |
Std Dev | 0.000002 |
Max | 10.00028 |
Min | 10.00026 |
34410AAverage | 10.00026 |
Std Dev | 0.000006 |
Max | 10.00027 |
Min | 10.00024 |
Based on the temp/humidity logging over the entire two hours, the temp was rising slowing from 27.0 to 27.7°C. The 34410A's voltage was similarly rising, unlike the 34401A. The next time the roving standard comes around I hope to have the ability to do all-night logging to better see the stability.
During this run, I also had a Keithley 2700 attached to the SVR-T. I don't have it set up for logging right now, but it was even closer to 10V than the 34410A. Right now, the displayed values are as follows:
34410A: 10.00010
34401A: 10.00026
K2700: 10.00007 (Cal unknown)
Here are some other meters I hooked up for a quick check. The Keithley 196 and Fluke 8100A warmed up for about half an hour. The handheld Keysights and Greenlee warmed up for about five minutes.
K196: 10.00035 (Cal unknown)
F8100A: 10.002 (Cal unknown)
U1272A: 9.978 (Cal exp. 6/2013)
U1282A: 9.998 (Cal exp. 12/2017)
U1252B: 10.000 (Cal exp. 10/2017)
DM-820A: 10.00 (Cal unknown)
As for the 9764.02 pF capacitor in the box, here are the values I got.
34410A: 9.7689 nF
U1272A: 9.691 nF
U1282A: 9.789 nF
U1252B: 9.764 nF
DM-820A: 9.77 nF
M12864: 9711 pF
The M12864 is a version of the "$20 transistor tester".
Note: I've updated the TiSensorLogger.488 program on the USB stick and
attached to my post. Changes include the following:
- Code tidying
- Flush bad data prior to the start of logging (the first temp and humidity samples are always wrong)
- Configurable logging interval (in seconds)
- Throw an error if unable to connect to COM port
- Blink right-most LED on EZGPIB UI while logger is running
@RandallMcRee: I'll be dropping the package off at the Post Office on Monday. You'll probably get it Tuesday or Wednesday.