OWON XDM1041 the unknown multimeter...

[John+audio]

Farnell in the UK have just added this product to their portfolio of test equipment under the 'MULTICOMP PRO' brand name.

https://uk.farnell.com/multicomp-pro/mp730889/dmm-bench-10a-1kv-50mohm/dp/3972198?MER=TARG-MER-PLP-RECO-STM71233-2

£114.07 plus VAT

[bffargo]

Did some testing with a 1041 seeing how easy it would be to hack it into a 1241 with only a couple inexpensive parts.

The internal mains AC->DC power supply is labeled as 5VDC@2A. Actual power consumption measured by feeding in 5VDC from bench supply directly into the output pins of the built in one (not removing it from circuit) are as follows with screen brightness at 25%

Standby: 6.15mA
Boot: 160mA
Run (VDC mode): 100mA
I didn't test any other modes

The mains ground pin is connected all the way through on the negative power rail up until it connects to the meter board at which point it is isolated from the front inputs.

It seems a bypass switch (/ hard power off), a USB>LiIon>500ma(to 2A) charge+inverter board and a decent 18650 should be enough to keep it powered for about 10 hours for little cost and lots of room to put it in the back with the mains board removed.

Update: I finally hacked mine, and found out it doesn't need a full 5VDC into the logic board.  It gets by just fine with direct LiIon 3.x volt output and doesn't need to be boost converted back up to 5V as per the original AC>DC converter in it.

I used a tiny micro usb battery charger and a 18650 cell and connected that up to the AC>DC board, then feeding its second output (that is always kept at the voltage of the LiIon charge when on battery alone or ~4.2V when connected to a 5V input.

To my surprise it has been running fine at the lower voltage without issues. I presume it may be dropping to 3.3V or so anyway once on the logic board, but didn't go poking around to verify.

I thought I'd share for anyone else that wants to do a quick hack of the AC powered one into a 18650 powered version. Just need a couple 5 pin male XH2.54 male header pins and a 5 pin female plug with just 2 wires for voltage and you can bypass the feed through to the serial port then and connect up the battery/charge chip.

I didn't take a picture of my mod, but here is a quick drawing.

[luma]

I've designed a couple 3D printed solutions to mount the XDM1041/XDM1241 for a few use cases.

Here's a model for Gridfinity which lets you mount the meter to a base plate and then stack that into existing gridfinity solutions.  Check the video link below for a fantastic presentation of the Gridfinity system, it's really well thought out and great for electronics workspace organization.

Here's a model for the DDD Wall Control project (this one is my own project).  This system utilizes steel Wall Control pegboards to mount tools etc securely to a wall.  Parts are printed and press-fit like legos to create modular organization solutions for wall mounting.





Gridfinity explanation (entertaining as hell, worth a watch)

[robdejonge]

Does the new firmware or new device version (1241) still have the odd mV/V range situation?

[dreiscal]

The 2nd sequence seems to run a program automatically...
it is possible that this expects inputs for calibration but it runs quite fast not waiting for inputs.

I guess that. That's why I never run it...

By the way, did you try to contact support to request for the new version of firmware?
I tried many time, but they no even reply 

Does anyone know which TFT display they use?
I was looking for it but did not find with such a pinout.
D0...D7 - 8-bit Data
PB10 - CLK (Clock)
PB2 - DC (Data/Command)
PB1 - CS (Chip Select)

Any luck finding the display partnumber?
Mine got damaged and I cannot find a replacement anywhere. 

[UniSoft]

Any luck finding the display partnumber?
Mine got damaged and I cannot find a replacement anywhere. 

No luck...

[diogoc]

Received my XDM1041 today.
It have version 4.0.0
For now I dont see big issues, all works fine including the software and datalogging export.
I would like only to have the possibility of saving the speed mode.

Regarding the hardware I liked that they used two large ceramic fuses.
There are some small changes in the pcbs but the schematic seems the same.
In the mcu board they changed the LDO to a switching regulator.

[atat]

Downloading recorded data...

one of XDM1041's (useless?) features is the possibility to record up to 1000 data points. The list can't be examined while recording is going on (why???) and every new recording erases the data already collected (in auto mode).

No scpi commands are documented, otherwise known or appear obvious by looking at the firmware that allow the export of the recorded data. As far as I can tell, this is impossible with current firmware.

However, every now an then, someone states that he or she had downloaded the recorded data (presumably using DMMEasyControl) - as opposed to logging a new set on the PC. Can any of these persons step forward and confirm their successful download?

In that case, I'd be very interested in tracing the scpi commands used.

[diogoc]

At least in version 4.0.0 it is possible do download the recorded data using using DMMEasyControl.

This repository have the list of scpi commands:
https://github.com/TheHWcave/OWON-XDM1041/tree/main

However, none is documented for downloading the datalog.

You can try to trace the commands used by DMMEasyControl.

[vk3em]

Just bought one from Amazon which had the best price I could find in AU $159 AUD
https://www.amazon.com.au/dp/B0BCFS1JHR

[oxygen]

I ordered XDM1241 from aliexpress and came from Czech .
Opened it. There was TWO 18650 2200mAh cells in parallel.
Taped in cell holder, but the tape was not stick good from one side ant cells was almost fallen out. One does not make contact, the other did.
2325 is Year/week code.
Consumption from USB-C without cells installed is about 300mA.
Does anyone measure charging current so far?
Edit: charging current about 1.6A (rough) for both batteries total
Batteries are quite different as capacity. Could be thah on was out of socket, or just cheapest cells.
Purchased 2 Panasonic NCR18650B for replacement
Attached few initial photos.

[EM84]

Just sniffed the communication while DMMEasyControl downloads recorded data from an xdm1041. It is a simple (undocumented) SCPI command, it spills out a comma separated list of the table values:

int:record?

[oxygen]

Can measure temp with K thermocouple. Can show current temp, min, max and mV on screen in the same time.
Nice

[masta_k74]

@bffargo
You could also simply connect a shottky diode from the USB 5V pin to the output of the power supply unit. Then you could supply the device via the USB port. According to your tests, the few hundred millivolts lost at the shottky should not be a problem. The power consumption is also low enough not to cause any problems when connected to a PC. An ordinary power bank, which I'm sure almost everyone has lying around, would be a good idea.
That's what I'm going to do. It can't hurt to have an optional power supply.

[ionut22]

Hello,

Somebody can help me with calibration file for version V4.1? I pressed auto calibration button from hidden menu and after that i find this topic!

Thankyou!

[Proxy64]

I just got mine, version 4.2
Is there an app running on Macos ?

[MF-jockey]

My OWON XDM1241 arrived today, it is also version V4.2.0.
I measured the current consumption directly on the battery
The quiescent current of 1.074 mA was shocking. This means that within half a year the fully charged batteries (2x approx. 2000mAh = 4000 mAh) are completely discharged. So you have to make sure to charge the device regularly every three months.
In operation, the current consumption is highly dependent on the display lighting: 0%=78mA, 25%=112mA, 50%=144mA, 75%=175mA, 100%=202mA.
On my reference voltage source 5 V, the XDM1241 shows 4.9994 VDC. The reference was measured by the supplier in November 2019 at 5,000.37 V, I cannot judge the current accuracy.
At the reference 10 V (specified as 10,000.66 V) 9.996-9.997 VDC are displayed, in the 500 V range exactly 10.00 VDC.
The brightness of the display and the connection of the power supply (USB) have no influence on the measured values.

[ClubFoto]

I have been working with XDM1241 version 4.2 for a few months and I have found that the capacitor measurements are wrong and in other cases it indicates out of scale, with values ​​that should read correctly.
I have tried to calibrate using the method explained in the thread, but I cannot find the appropriate values.
Can you tell me if this model can be reset to factory settings, use an automatic calibration or, failing that, what values ​​to use to calibrate the capacitors.

[ClubFoto]

How is the calibration file generated?
Could you please tell me the values ​​that appear in the capacitor calibration?