DC V & A logging

[mojoe]

Is there a relatively inexpensive data logger (preferably to a PC) that simultaneously records DCV & DCA? I only need up to 50 V & 20 A. If the software will calculate Watts for me, that would be a bonus.

I can log either one with a meter I have, but not both at once.

Edit: Never mind. A search on Amazon only turned up expensive options. However, an internet search turned up this Amazon item on Reddit (go figure).

0-300 DCV, 0-50 DCA (or more) with shunt: https://www.amazon.com/PEACEFAIR-Consumption-Communication-Measurement-Interface/dp/B0D2W4YKPS

No reviews, but for $24, I'll take a chance. I'm not sure if it comes with software.

[mojoe]

I found the manufacturers site, which lists the protocol, and shows a picture of Windows software. However, I can find no download link. I just emailed them about this.

https://en.peacefair.cn/product/786.html

It seems that there are several other programming efforts for these products. I found a web app, some Python code, and some Arduino code.

[mwb1100]

The vendor might respond with some better information, but the Amazon listing gives basic info that could get you started.  It mentions that the unit communicates with the modbus RTU protocol (see also https://modbus.org/docs/PI_MBUS_300.pdf) at 9600-82N.

The registers for the various configuration items and data items are given in the Amazon listing as:

Register address Description Resolution

0x0000 Voltage value 1LSB correspond to 0.01V
0x0001 Current value 1LSB correspond to 0.01A
0x0002 Power value low 16 bits 1LSB correspond to 0.1W
0x0003 Power value high 16 bits
0x0004 Energy value low 16 bits 1LSB correspond to 1Wh
0x0005 Energy value high 16 bits
0x0006 High voltage alarm status 0xFFFF is alarm,0x0000 is not alarm
0x0007 Low voltage alarm status 0xFFFF is alarm,0x0000 is not alarm

Register address Description Resolution

0x0000 High voltage alarm threshold(5~350V), default is 300V 1LSB correspond to 0.01V
0x0001 Low voltage alarm threshold)1~350V), default is 7V 1LSB correspond to 0.01V
0x0002 Modbus-RTU address The range is 0x0001~0x00F7
0x0003 The current range 0x0000: 100A 0x0001: 50A 0x0002: 200A 0x0003: 300A

[Fungus]

You don't mention accuracy or any other requirements but my first thought is to get an Arduino and a few resistors...

[kloetpatra]

I have successfully used this for logging U/I/P via WiFi to PC using python. The advantage with this is galvanic isolation. There is even a 600A version, however resolution depends on the version.
https://de.aliexpress.com/item/1005007168934730.html

[mojoe]

Those look quite nice, and the WiFi is a plus. The device I linked doesn't have a display, but the RS-485 is optoisolated. I already ordered one from Amazon.

[mojoe]

For those using the PZEM-003 or PZEM-017 RS-485 Modbus devices, I found this program, which allows me to log data. It is very easy to use.

https://github.com/ModbusScope/ModbusScope

BTW the software from Peacefair is only good to see if the device works. It doesn't log data.