Info for anyone searching for Keithley DMM6500:
Problem identified, it was not caused by the DMM6500
Reason was -> User / cable failureIf you are still interested, read on...
Hello forum,
I am following this forum for a few years but never had any content to share, so never registered.
Background:
Since about 5 years i wanted to get hold of a decent bench DMM, but never bought one. In summer this year i discovered the Keithley DMM 6500 and was collecting every information i could get.
Finally in october, I decided to buy.
So, here I am, proud owner of a factory new Keithley DMM6500!
To give you guys a short info about my level of experience: I'm more like a type of hobbyist just having fun with equipment, most time not producing or creating anything.
.
I've been playing around a bit and I'm really pleased with the DMM, except my confusion with the following:
The attached screenshots show a measurement with 2w resistance function, DMM was allowed to warm up for > 1 hour.
The measured resistor is a Dale, 1ohm, 1%, 25w (4wr measurement result is ~1.0003 ohm).
The measurement was not zeroed / referenced to the test lead resistance.
I was expecting noise because of 2 wire (and the uncertainty of 100mOhm as of specs), but why the downwards drift and those spikes? (Equipment was not touched during measurement, no other devices nearby turned on or off).
I have nothing comparable in terms of resolution or accuracy (only 2 pcs Uni-T handhelds), so I don't know if this is normal.
Is this supposed to show such behavior for 2wr?