Components: USB M-Bus Master for 20 Loads

Mon, 01 Jan 0001 00:00:00 +0000

These informations are provided “AS IS” and without any warranty of any kind.

This module provides a very convenient way to operate a Wired M-Bus via USB. It takes the role of the M-Bus Master.

Unlike most other M-Bus converters that expect TTL or RS485 inputs, it already comes with an USB-Serial converter built-in.

And while the CH340 might not be one of the best performing ICs, it certainly gets the job done for wired M-Bus communication, which usually ranges from 300 to 9600 bits/s.

Pros

20 M-Bus loads (~1.8 W) is pretty much the maximum that one can power from an USB port, considering DC-DC conversion inefficiencies
PCB and components seem to be pretty good quality, works flawlessly
USB Type B Socket, Plug-in Screw Terminals and its compact board design make it a perfect choice for DIN Rail mounting
Decent price-performance ratio

Cons

Markings have been removed/lasered from most ICs, making it impossible to identify individual components
Barely possible to find any official information about this module

General Overview / Specs


Model	USB To M-Bus Master (6832-chong ???)
Manufacturer	UNKNOWN (Dykbcells / DYKBmetered ???)
Made in	Mainland China
Power Supply Voltage	5 V (USB)
Max. USB Current	500 mA
Max. USB Idle Current	25 mA
USB Connector	USB 2.0 Type B Socket
USB Serial Vendor	`1a86` QinHeng Electronics
USB Serial Product	`7523` CH340 Serial Converter
Max. communication speed	300–115200 bps auto-adaptive
M-Bus Connector	Plug-in Screw Terminal 5.08 mm
M-Bus Voltage	36 V (idle) / 24 V (transmission)
Max. M-Bus Loads	20 w/ 1.5 mA each
Max. M-Bus Current	50 mA (20 * 1.5 mA + 18.5 mA = 48.5 mA)
Protections	Over-Voltage/-Current, Short-Circuit, ESD
LED Indicators	Power, TX, RX
Dimensions	84.5 × 45.0 × 25.5 mm
Operating Temperature	-25°C to +70°C

Availability / Order

AliExpress

Case / Mounting / DIN-Rail

3D Printed Case

I’ve designed a DIN-Rail mountable case for this board, it is available on eBay.de

As most of my cases for electronic devices, it has been printed using insulating and flame-retardant (UL 94 HB) DuraPro ABS filament from Extrudr.

Specifications: DR-Case-USB-B-MBUS20.specs.pdf

STL Files for 3D Printing

The .stl files for the DIN-Rail case will soon become available on Cults3D.com

j3w5.de – USB ↔ M-Bus Converter