Sorry for the long post, tried to address everyone in single reply.
These meters are rarely used with high voltage / high power.
I was able to trace the stickers on mine to a big battery company that makes cells and packs for cars.
Just to avoid a misunderstanding: how is the 10 A range not working: too high a resistance and thus no current (like an open fuse) or is it just not reading anything sensible. This would be quite different faults. With the extra terminal for the 10 A range there should not even be a relay in the path and the 10A range is via the rear terminal only and thus no front-rear switch either.
Seems to be not reading anything. It will drop my power supply directly into constant current. My PSU has a meter for the output and I can see the voltage drop to mV and acts just like if I short the PSU out. That’s why my first thought was the current sense resistor but it read correctly, although I didn’t think about checking the sense wire.
10A range is direct, through only a fuse and the shunt itself:
Seems to be the same one. It measures the same also at 5mΩ when I checked it with a kelvin miliohm meter.
I'm assuming there is a kelvin connection to the other side of the shunt not easily seen in that pic. While it is on the main board unlike the DMM6500, I think the concept (and probably parts used) is the same, without even a shunt diode bridge (probably of no use across such a low value shunt resistor).
Might be a bit tricky to trace where the kelvin sense goes from there unfortunately 
Looking at pic comparing the units it looks like the same one. The sense wire is one of the things that goes to the rear/front switch, from there I am not sure. I didn’t dig that far.
Voltage at startup should be ignored, even if you just reset the meter after running for a couple hours. I would leave the meter running for a week before you think too seriously about calibration and accuracy on that level.
But, but, but…. I want to…… lol. It was almost at a 5 days running with only a few restarts, firmware update. But it had a cool down with a power outage last night for 2 hours.
You also have to consider the environment during testing and how that differs from the calibration of the voltage source. Only if the temperature and humidity are identical between the voltage source and your room, the question becomes which device is in or out of calibration.
Understood, and all valid points. My temp and humidity hasn't been that far off from the PDVS 2. The DMMCheck has a lower ambient temp for cal, both also new as of last week. Third source is DYI and was calibrated with my 34401A after the meter was calibrated 10 years ago to track its drift. I wouldn’t expect that the last 2 digits to match on any of the sources with the DMM7510, but that 4th zero I would think should given its accuracy and the sources used like I have seen on so many other videos and on my 34401A.
If you want to send your DMM7510 for calibration, try and find a lab that also includes adjustment (corrections).
Thanks, that’s an idea I didn’t consider, or even know was an option. For now I am holding off on the calibration since he’s talking about sending me a shipping label to return it for a refund. I don't want to deal with looking for another and custom fees again but might not have a choice. I’ve learned to really like this meter, so if it goes back I might just buy one in the US thats already calibrated for the sale and put the extra money in.
Hey, Scott, may I suggest checking the calibration menu? Just to see how many times and when it was calibrated. It could be previous owner did something with it.
It only has the manufacturing date cal and no auto cal shown. I thought maybe I got lucky with a unit that is less than 4 years old but now I think I know why it’s younger with the 10A part blown out.
I'd also try to swap leads and see what you get. That should also reveal if there is any thermal emf.
Also, on my unit default settings, imo, suboptimal. I put 5PLC and line sync.
BTW, lastly, you absolutely sure your tiny little device outputs right voltage? I assume you cross-checked that with other DMMs you have.
EDIT: and set impedance to AUTO, not 10MEG.
Yup, multiple sources, multiple cables, short and shielded ones also. There is a suggested procedure in the manual for mV DC readings, I think it’s 10PLC and repeat filter 100, impedance at AUTO in lower ranges. I have found that 5PCL is good enough and 30 to 50 repeat filter, but I have done both. The 1V range and above the filter at 10 seem to grieve the same results, and 5PLC is ok in my opinion.
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