Voltcraft M-3850 Manual

M-3850 USB Interface

Look here, what I have found while rummaging through some of my boxes, filled with noble electronics junk.It's a serial interface cable for my Voltcraft (Metex) M-3850 multi meter.Judging by the DB-25 connector this thing can truly be considered to be antique by now.Wouldn't it be nice to make it connect to a USB port instead?It certainly would make a nice, short, quick, in-between project.

Voltcraft M-3850 Manual Download

Metex m-3850 manual Hi, i find this topic about M-3850, but i don't have enough points. Can you send me via mail, pls? Jan 30, 2007 #4 N. N0body Newbie level 3. Multimetrvoltcraft4660a128686multi.pdf: 21/11/16: User Manual (en,fr,de,nl) Portable Bench Top True RMS digital meter: 215 kB: 507: Metex: MXD4660A: Precaution.pdf: 25/09/12: Request: User Manual (English Version) Portable Bench Top True RMS digital meter: 158 kB: 293: Metex: MXD 4660A: Product%20Specification.pdf: 25/09/12.

  • When you are looking for Metex model number M3610D M-3610D, M3650D M-3650D, M3830 M-3830, M3850 M-3850, we have the parts and repair manuals you require to properly fix the Metex device. Our service manuals are available in hard copy, CD ROM and.pdf formats.
  • Metex m-3800 manual. Metex m-3800 manual, metex me-11 manual, metex m-3650 user manual, metex m-3610 d user manual, metex m-4650 manual, metex 3800 manual, metex ms-9140 service manual, metex ms-9150 manual, metex m-3850d user manual, metex m 3270 d manual, metex m3650d manual, metex m3800 manual, metex 3850 manual, metex me-31 manual, metex m.

Serial Interface

The serial interface of the M-3850 is electrically isolated from the potentially dangerous input voltages by 2 opto-couplers.Adding two resistors and 5 wires and you've got the entire serial interface.These 5 wires go directly to the DB-25 connector.The DTS and RTS lines of the serial interface are used to provide 'power' to the circuit.DTS supplies the +12V, while RTS supplies the -12V.
Fortunately we can't be bothered about these signals.We can simply drive everything from 5V, supplied by the USB interface.

USB To Serial Converter

For this purpose I use a ready made converter from Banggood.I couldn't find the exact same one I've bought anymore, but there are plenty of other modules to choose from, even smaller ones than the one I've got.Choose a module which has a selectable 5V or 3V3 I/O level.The interface runs on 5V logic levels.
All the header pins were removed from the USB serial module to make it more compact.A jumper wire is used to select the 5V I/O level.Four of the 5 wires, which originally were soldered to the DB-25 connector, are soldered to the PCB.The yellow wire has no purpose any more and can be cut short.The blue and brown wires are both soldered to the GND plane of the USB serial interface.The red wire is soldered to the TxD terminal of the desoldered header, while the green wire is soldered to the RxD terminal.And that is basically all that there's to it.
I have filed a few small indents into the side of the board, which are used to hold a cable tie, which straps the cable down to the board.A 1' shrink wrap sleeve is used as a poor man's housing for the PCB.Maybe, someday, I will be able to 3D print a more elegant housing for the PCB.But for now it will do.

Communicating With The M-3850

Communication is done at a whopping 1200 baud, with No parity, 7 data bits and 2 stop bits.Press the instrument's function key several times until you see the 'COM' annunciator in the display.Please note that other functions, like REL, MIN, MAX are not possible while communicating with a computer.

Messages from the multi meter always consist of 14 characters, no matter what function or range the meter is in.Here are some examples:


The M-3850 is a battery powered device, which switches off after a while to preserve battery power.Why does it also switch off while the instrument is in the COM mode?I consider that to be a stupid bug in the software.
Alas, it's the way it is, we'll have to live with it.You can occasionally press the back light button to keep the meter from falling asleep.This isn't of much help of course if you want to use the meter for long duration, unattended logging.

Each output string consists of 14 characters, the last one being a CR character, regardless of the meter's function.Except for the diode test function and both temperature functions, which don't transmit the closing CR character.As long as the diode function displays Overload everything is OK.Any other value will be printed on one single line, without any CR characters.
At least, that's what my meter does.

Type: (PDF)
If you get stuck in repairing a defective appliance download this repair information for help. See below.
Good luck to the repair!
Please do not offer the downloaded file for sell only use it for personal usage!
Looking for other manual?
  • Also known:
    METEX M-38503830 M38503830 38503830 M3850 3830 M3850-3830
  • If you have any question about repairing write your question to the Message board. For this no need registration.
  • Please take a look at the below related repair forum topics. May be help you to repair.
If you are not familiar with electronics, do not attempt to repair!
You could suffer a fatal electrical shock! Instead, contact your nearest service center!
Note! To open downloaded files you need acrobat reader or similar pdf reader program. In addition, some files are archived,
so you need WinZip or WinRar to open that files. Also some files are djvu so you need djvu viewer to open them.
These free programs can be found on this page: needed progs
If you use opera you have to disable opera turbo function to download file!
If you cannot download this file, try it with CHROME or FIREFOX browser.Voltcraft m 3850 manual

Metex M-3850 Manual

Egy METEX M-4650 műszert javítanék.
Hiba: Minden kapcsoló állásban ' 1 ' -et mutat. Méréshatár váltó az működik , digit pontok változnak a méréshatárnak megfelelően, AC is kiíródik, meg szakadáskor sípol is, de nem mutat mást csak 1-et.
Lenne valami ötletetek? Esetleg azokat a fránya IC2 , IC4, IC5 modulokat honnét lehetne beszerezni?
Sziasztok! Lévén egy Metex-M3650.CR nevü müszerem. A méréshatára frekiben:200khz. A méréshatárát szeretném kibőviteni 2Mhz és 20Mhz-re. A műszert lehetőleg nem szeretném megbontani. Valamilyen előosztóban gondolkodom!? Ha van valakinek egy jó ötlete megköszönném. Űdv:József :?:
Helló! Hibrid IC-ről a kerámia bevonatot kellene valahogy eltávolítani,feloldani javításának céljából de nem kapargatással. Ha esetleg van ötlete valakinek?
Sziasztok Szeretném kérni valakinek a segítségét, egy Metex M-3850.-es műszerem hitelesítésében. Sajnos az utóbbi időben az ellenállás mérésnél, ha rövidre zárom a két mérőkábelt, 2.6 Ohm ellenállást mutat. Nem tudom hogy ez az eltérés a frekvenciában, vagy bármilyen más mérésénél milyen eltérést eredményezhet. Nincs szkópom, így csak a segítségre támaszkodhatok. Előre is köszi. Tibi
Similar manuals:
If you want to join us and get repairing help please sign in or sign up by completing a simple electrical test
or write your question to the Message board without registration.
You can write in English language into the forum (not only in Hungarian)!