GDM-8351 DMM calibration procedure

[kakci]

Hello!

I'm looking for the calibration procedure on this DMM or service manual if anyone has it.

[coromonadalix]

Question,  did you ask Gw Instek ??

[kakci]

Yes heres the answer:

"IF you find that your unit is giving false readings and it has to be adjusted/repaired, then this can only be done by GW representative."

I was asking for the calibration procedure.

Trying to ask here since someone succeeded with the GDM-8251 calibration procedure and posted it here. But the 8351 doesnt have an USB Type-A port.

[PeZe]

Hello everyone,

Has anyone made any progress with the calibration procedure for this multimeter?
I just got it second hand and would like to do a calibration/adjustment.

So far what I have been able to find is that the procedure from the older model which had a dedicated USB port for the calibration key cannot be used as it is missing on this model.
I have also asked GW instek support for the procedure but the reply was clear - they will not share it unless you are an accredited laboratory or authorised distributor.

[Martin72]

Hi,

I just got it second hand and would like to do a calibration/adjustment.

Is that necessary, how did you find out?
Do you have the appropriate means for such a calibration?
If not, I would have the meter calibrated externally if I were you.

[coromonadalix]

must be deon by scpi commands or dedicated software ...   

maybe decompile a fw upgrade file to see the inner commands ?  if such a file is available ?

in last resort   send it to a cal facility ...

[PeZe]

Yes, DC values are off by 2 digits on some ranges.

I have at my disposal calibrated higher count DMMs and accurate voltage/current calibrator - we are used to calibrating uncritical equipment at work by ourselves.
So it is not a matter of equipment or metrology skills.
 
Of course sending it to a certified lab for adjutment is an option, but for my home development I do not exactly need acredited protocol for it... Especially it is a pity to spend the money when I have the equipment available to do it myself...   

I wonder why Instek is going this way as other manufacturers are going the open way and some of them provide calibration details directly in the manual...

I was just curious if anyone has been successful in obtaining the procedure since the last discussion in 2019, but I get it, these DMMs and not as popular as KEITHLEY or KEYSIGHT etc...

[Kleinstein]

The specs allow for quite some tolerance, including at least 5 counts. So 2 counts off from the right value would still be well in spec.

For home use there could still be option to note down the difference / correction factor and for the few measurements that one really minds apply this.
If one has a better meter, chances are one would use that meter for the critical measurements anyway.