GDM-8351 DMM calibration procedure - Page 1
Forum section: electronics / testgear

author: kakci
author_rank: Newbie
timestamp: April 30, 2019, 09:23:54 pm
content: Hello!I'm looking for the calibration procedure on this DMM or service manual if anyone has it.

author: coromonadalix
author_rank: Super Contributor
timestamp: May 01, 2019, 07:53:30 am
content: Question, did you ask Gw Instek ??

author: kakci
author_rank: Newbie
timestamp: May 01, 2019, 08:12:13 am
content: 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.

author: PeZe
author_rank: Newbie
timestamp: May 19, 2024, 09:42:52 pm
content: 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.

author: Martin72
author_rank: Super Contributor
timestamp: May 19, 2024, 10:37:04 pm
content: Hi,QuoteIs 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.

author: coromonadalix
author_rank: Super Contributor
timestamp: May 20, 2024, 03:45:40 am
content: 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 ...

author: PeZe
author_rank: Newbie
timestamp: May 20, 2024, 08:21:06 pm
content: 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...

author: Kleinstein
author_rank: Super Contributor
timestamp: May 21, 2024, 08:09:29 am
content: 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.