Teardown Multimeter Norma D 3012 - made in Austria not in Australia - Page 1
Forum section: electronics / testgear

author: WackyGerman
author_rank: Regular Contributor
timestamp: February 07, 2015, 08:52:09 pm
content: Here are the pics from the teardown of the Norma D3012 I bought on the fleamarket . From outsite it is not a beauty but it is in good working condition . On some components I found the year of manufacturing , it is in the early 80 s . Just look and have a good time

author: WackyGerman
author_rank: Regular Contributor
timestamp: February 07, 2015, 08:53:44 pm
content: and the next pics

author: WackyGerman
author_rank: Regular Contributor
timestamp: February 07, 2015, 08:54:52 pm
content: and the last one

author: Wytnucls
author_rank: Super Contributor
timestamp: February 07, 2015, 09:11:00 pm
content: Wow, did you count the trimpots?

author: WackyGerman
author_rank: Regular Contributor
timestamp: February 07, 2015, 09:16:23 pm
content: No I didn t count them yet. I leaved the trimpots untouched because for me the accuracy is more then enough . I checked it with the dmm check and the penta ref and the values are ok

author: Paul Moir
author_rank: Frequent Contributor
timestamp: February 07, 2015, 09:37:19 pm
content: I wonder what the trimcaps (and FWIW, the inductor) are for!

author: dom0
author_rank: Super Contributor
timestamp: February 07, 2015, 10:55:03 pm
content: Maybe AC response trim or something like that, although I doubt that it's true RMS.

author: WackyGerman
author_rank: Regular Contributor
timestamp: February 08, 2015, 05:04:07 am
content: No it is not true rms . When I measured the square wave reference voltage from the DMM Check 5 V it is 11 % off . Here is a datasheet of the meter

author: Paul Moir
author_rank: Frequent Contributor
timestamp: February 08, 2015, 05:33:02 am
content: Ah, 80pF in allen Bereichen. That might explain them?No small effort on that meter when you look at the datasheet.

author: Vgkid
author_rank: Super Contributor
timestamp: February 08, 2015, 06:24:03 am
content: There are at least 21 trimpots in that meter, my broken solartron bench meter only has 17.

author: codeboy2k
author_rank: Super Contributor
timestamp: February 08, 2015, 08:31:02 am
content: Seriously, that's a nice bench meter for it's time, at 0.03% DC ... better if it's still in spec as you sayI would expect that all the trimpots are used to get the accuracy at all the ranges without having to use expensive precision parts.These days it's all done in software.Thanks for the teardown.EDIT: I think I see some voltage trimmers too.ALSO: did you find a microprocessor?

author: WackyGerman
author_rank: Regular Contributor
timestamp: February 08, 2015, 08:55:23 am
content: yes it is still in spec except at 1 V DC it is a little off . But I don t overrate it too much . The multimeter measures 1.0004 V at 1.0000 V output from my PentaRef so it is 0.01% off the spec . For me it is more than good enough .Well I also didn t find any microprcessor on the board

author: dom0
author_rank: Super Contributor
timestamp: February 08, 2015, 10:17:36 am
content: Quote from: WackyGerman on February 08, 2015, 08:55:23 amExplains the many trimpots: at least two (offset & gain) trimpots for each range.Directly measuring up to 2 kV is interesting, many DMMs can't do that (assuming the isolation is still ok)

author: Tomyx
author_rank: Newbie
timestamp: October 03, 2015, 08:31:37 pm
content: hi all, this is my first post.I got this beauty for under 40 euros and is a little bit diferent than what i seen here, as u can see it have a printe port.in the picture below i found those 2 wires disconected but the unit work perfectlyi supose they are disconected from here because they are long enought to get conected there (see in picture below)if anyone have the schematics or a service manual i would be grateful. I was looking the web for more info about this model but didnt find anything more than 1 page with specs

author: WackyGerman
author_rank: Regular Contributor
timestamp: October 24, 2022, 08:24:17 am
content: Just google for the Siemens B1040 manual . It`s a rebranded model of the Norma . In the manual you will also find the schematics of the multimeter itself and the printerporthttps://bama.edebris.com/download/siemens/b1040/Siemens-Multimeter-B1040-B1041.pdf