Not to interrupt this thread, but I think it's only fair to mention that the new DMM I received today from CN Rood was calibrated a lot more recent (September 2019). The fan and hum are about the same loudness.
Thanks for the clarification, like I said I am fairly sure this issue is logged. The next hardware revision will seek to improve it because we address all known defects. I can say however, that I dont know of any mechanism in place to notify you when this actually occurs. In the meantime, perhaps somebody (Brad) could work on a way for the issue to be worked around for your particular measurement situation (if there is such a way). I'm assuming you posted sufficient details on the Tek forum.
Somewhere in the future I would like to measure temperatures with the DMM6500. I understand it doesn't measure the cold junction temperature. So the exact temp difference is somewhat hard to tell. This can be overcome to use a known cold junction/junction temperature outside the device.
Maybe you can shine some light on the limitations of MULTI-MEASURE of voltage and current (excluding the 100V range bug)
In this thread we checked other DMMs (not Keithley) and also much more expensive DMMs and they all have this xx mV reading when running 1A through the device.
So that seems to be a common thing to happen, that is how it should work.
But how does Keithley or any other manufacture then say voltage can be measured while current is running through the device? Seems to me the best you can say is it can be done but then the voltage is completely out of spec.
Anyway it's better to have it and understand what the limitations are than having it disabled.
From what I experience it's rarely a good idea to do both on one device hence why I don't really worry about the 100V range bug.
I just want to clarify since we didn't really compile a list of DMMs that perform dual V/I measurements and test them. The DMM7510 doesn't suffer from this same hardware problem, it does dual measurements fine and provides the expected results on the voltage reading. While both the DMM6500 and DAQ6510 cannot perform a reliable dual measurements on either the 100/1000V ranges.
Somewhere in the future I would like to measure temperatures with the DMM6500. I understand it doesn't measure the cold junction temperature. So the exact temp difference is somewhat hard to tell. This can be overcome to use a known cold junction/junction temperature outside the device.
You cold also use another sensor type.
Maybe you can shine some light on the limitations of MULTI-MEASURE of voltage and current (excluding the 100V range bug)
In this thread we checked other DMMs (not Keithley) and also much more expensive DMMs and they all have this xx mV reading when running 1A through the device.
So that seems to be a common thing to happen, that is how it should work.
But how does Keithley or any other manufacture then say voltage can be measured while current is running through the device? Seems to me the best you can say is it can be done but then the voltage is completely out of spec.
Anyway it's better to have it and understand what the limitations are than having it disabled.
From what I experience it's rarely a good idea to do both on one device hence why I don't really worry about the 100V range bug.
I just want to clarify since we didn't really compile a list of DMMs that perform dual V/I measurements and test them. The DMM7510 doesn't suffer from this same hardware problem, it does dual measurements fine and provides the expected results on the voltage reading. While both the DMM6500 and DAQ6510 cannot perform a reliable dual measurements on either the 100/1000V ranges.
I'm not talking about the 100/1000V bug I'm talking about this:
50 ohm between voltage terminals, I could add a voltage and then say it's wrong but I don't see the point, it's not 0.0mV now without one.
DMM6500. Datasheet :
http://www.farnell.com/datasheets/2585589.pdf
Good to see ethernet standard, even if they got it backwards
Somewhere in the future I would like to measure temperatures with the DMM6500. I understand it doesn't measure the cold junction temperature. So the exact temp difference is somewhat hard to tell. This can be overcome to use a known cold junction/junction temperature outside the device.
You cold also use another sensor type.I haven't investigated other options yet. But the solution should have a good price/fun ratio
One of the advantage of a K-type sensor is that they're cheap (don't know about price vs quality) and their low thermal mass and large measurement range. But if someone knows of another affordable solution, then I'm certainly interested.
Will the need arise to do temperature measurements it's nice to have multiple options at hand.
Somewhere in the future I would like to measure temperatures with the DMM6500. I understand it doesn't measure the cold junction temperature. So the exact temp difference is somewhat hard to tell. This can be overcome to use a known cold junction/junction temperature outside the device.
You cold also use another sensor type.I haven't investigated other options yet. But the solution should have a good price/fun ratio
One of the advantage of a K-type sensor is that they're cheap (don't know about price vs quality) and their low thermal mass and large measurement range. But if someone knows of another affordable solution, then I'm certainly interested.
Will the need arise to do temperature measurements it's nice to have multiple options at hand.
I've been happy enough with this PT100 probe with the DMM6500. I personally just clipped the wires and soldered on some banana plugs. It is accurate enough that I don't feel like I need to perform a cold junction compensation for it with an ice water bath. Unlike all the K-type probes I've used (they all required compensation).
https://www.amazon.com/gp/product/B075QC399C/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
You can also find the same probe on aliexpress if you search around.
RTD sensors (PT100, PT1000) don't need cold junction compensations. That is needed for thermocouples. RTDs are absolute value sensors. Same with thermistors, but they have quite different resistance/temperature curve..
With just standard 4 mm connectors it is hard to use thermo-couples.
Looks like us Canadians will have to wait, till after the US long weekend.