I'm currently running the Service note 18 drift test, and am already way out of bounds after a few days
The error bars on the CAL72 values are set to 3.4E-5 percent of the reading which I think is the 0.34 ppm magic number.
The meter was powered on after a long period in storage on the day before the first reading in the graph.
Is this a definite case of "you need a new A3 board", or is there some hope that it can be fixed or will stabilise after a few more days?
Thanks
Dave
I'd leave meter to run a week or two after storage and then do the test. You may have got just long storage stress.
Keep measuring before spending money
My Solartron 7081 has an interesting maintenance procedure after being in storage: wrap it in insulation and keep it powered for 24 hours to raise the internal temperature.
I used a blanket, and the internal temperature rose to, IIRC, around 40C. It was noticeably better thereafter.
I make no comment about the relevance or otherwise to your 3458.
Doh! It's nowhere near as bad as I initially thought - the limits are 0.43ppm per DAY, not 0.34 per week which is what I had misremembered!
I've since updated the spreadsheet to set the errors bars at 4.3E-5 percent.
The only period in which the limit was exceeded was the first one where the delta was 0.9ppm.
The next 24 hour drift was 0.13ppm.
So fingers crossed!
Dave
It's probably fine, and you'll probably see it settle down a bit more. Let it run for -at least- a few weeks after a long power-off storage period before gathering any serious data.
My 3458a despite having a jumpy reference with a horrible temperature coefficient A9 has a very good "resistor switch/chip".
23/12/2016 35.20 997.876849
09/01/2018 35.20 997.876575
0.3ppm per year seems to qualify as "good enough" also for the 0.34ppm per week (but also month or year)
My 3458a despite having a jumpy reference with a horrible temperature coefficient A9 has a very good "resistor switch/chip".
23/12/2016 35.20 997.876849
09/01/2018 35.20 997.876575
0.3ppm per year seems to qualify as "good enough" also for the 0.34ppm per week (but also month or year)
This looks impressive - has it been powered on for the entire time(it is only legit if powered on).
My 3458a despite having a jumpy reference with a horrible temperature coefficient A9 has a very good "resistor switch/chip".
23/12/2016 35.20 997.876849
09/01/2018 35.20 997.876575
0.3ppm per year seems to qualify as "good enough" also for the 0.34ppm per week (but also month or year)
This looks impressive - has it been powered on for the entire time(it is only legit if powered on).
No not 24/24, let say 20% ... anyway still impressive. It has the new analog board.
Inviato dal mio ONEPLUS A5010 utilizzando Tapatalk