PW100 User Manual
M-Bus Level Converter and Repeater for up to 100 Slaves
Main Features
- M-Bus Level Converter for 100 devices
- Transparent level converting of several interfaces to M-Bus
- Ethernet 10/100BaseT and USB 2.0 with driver for virtual serial port
- 2 x RS232C with terminals (TXD, RXD, GND)
- 2-wire RS485 interface (not addressable)
- M-Bus Booster with Repeater function for extension of M-Bus networks
- Galvanic isolation of all interfaces from M-Bus
- Intelligent access control of the interfaces by a microcontroller
- External power supply with wide range input for worldwide use
- Housing for rail mounting
Installation
2.1 Functional Principle
2.2 Mounting
The PW100 housing is mounted on a TS35 top-hat rail. The width of the housing is 6 horizontal pitches (6 HP) on the rail and, due to the low height of 60 mm, not only fits into a control cabinet, but also in a meter cabinet under the covers.
The device requires an external power supply of approx. 42VDC. We strongly recommend using our NT016 power supply. If the PW100 is operated with another power supply, the function of the PW100 may be disturbed. The NT016 also has a height of 60 mm and a width of only two module unit (2 HP). 
All terminals are pluggable and thus make wiring and replacement of the PW100 easier in the event of a fault.
Attention: Please make sure to put the clamps back in the correct place after removing them. Incorrectly positioned terminals can lead to defects.
Upper terminals (from left to right):
| Typ | Signal | Beschreibung |
| POWER | + / – | Output voltage of the power supply 42VDC (mind the polarity) |
| ⏚ | Protective conductor (earth) for symmetry and protection of the M-Bus | |
| M-BUS | – / + | M-Bus output, wires to the M-Bus meters, 3 pairs of parallel connections |
Lower terminals (from left to right):
| Typ | Signal | Beschreibung |
| ETHERNET | 10/100MBit RJ45 Ethernet socket for network connection | |
| RS485 | B- / A+ / GND | RS485 Interface, 2-wire, B = – / A = + / GND = ground reference |
| USB | USB connector of the internal USB-to-RS232 converter (FTDI) | |
| RS232 2 | TX / RX / GND | RS232C Interface No. 2, TX = PC transmits, RX = PC receives, GND |
| RS232 1 | TX / RX / GND | RS232C Interface No. 1, TX = PC transmits, RX = PC receives, GND |
| M-BUS REPEATER | M-Bus Repeater input for network extension |
2.4 LED indicators
There are in total six LEDs in the front part showing the status of the M-Bus. A lighted LED has the following meaning:
| POWER |  |
The M-Bus output voltage is switched on. |
| TRANSMITTING |  |
The Master transmits data. |
| RECEIVING | |
Minimum one meter replies with data. |
| MAX CURRENT |  |
The maximum number of connectable meters is exceeded (warning). |
| SHORT CIRCUIT |  |
M-Bus over current / short circuit (2 Hz flashing) |
| M-BUS ACTIVE | |
One interface is active and exclusively occupies the M-Bus. |
Two LEDs in the RJ45 Ethernet socket show the state of the network and the virtual comport. The LEDs have a reduced intensity of 20% of the normal value without a connected network cable. Once a network is connected, the brightness changes to 100%. The most important flash patterns have the following meaning:
 |
No connection established |
 |
A connection is active |
 |
A connection is established and a communication is active |
 |
Device Server performs a restart |
You can find all other patterns in the online help of the DS Manager (F1-button) in the chapter “Firmware Manuals / Device Server Application Firmware / Status LED Signals (Red = Green / Green = Yellow).
Description of functions
The PW100 is a transparent Level Converter from several interfaces to M-Bus for up to 100 meters. The device allows external connected controllers such as a building control, a DDC or a PC to read the connected meters by use of an M-Bus software (not in scope of delivery). The PW100 can also be used as a Repeater for extension of M-Bus networks relating to the cable length and number of meters.
3.1 Interface multiplexer / switch
An internal microcontroller handles the bus control to just give one interface access to the M-Bus even with multiple connected interfaces. This ensures that systems do not interfere with each other during the communication, when two or more systems are connected, for example a BMS via RS485 and a PC via USB. This automatic switch operates on the principle “first come, first served”, i.e. when an interface sends a signal to the M-Bus, this interface takes control of the M-Bus and has exclusive access to communication. The “ACTIVE” labeled LED indicates the activity status of the internal interface switch. While the LED is lit, one of the six possible interfaces is active. The other interfaces are disabled at this time and cannot access the M-Bus. The active interface remains enabled about 3 seconds after the last communication. Another interface can occupy the M-Bus as soon as the LED goes off.
3.2 RS232C interfaces
The PW100 has two independent RS232C interfaces, both of them as a 9-pin D-SUB as 3-pin screw terminals.
The RS232C pin assignments are:
RX = PC transmits to M-Bus, TX = PC receives from M-Bus, GND = Signal ground
If you want to connect a D-SUB cable, please use the additional, optional cable KA006 with 3 open wires.
To link to a PC (1: 1 connection), connect the 3 wires as follows:
| D-SUB | Signal | Funktion PW100 | Farbe (Klemme) |
| Pin 1 | DCD (data carrier detect) | unused | |
| Pin 2 | RXD (PC receives data) | M-Bus sends data to PC | Green (TX) |
| Pin 3 | TXD (PC transmits data) | PC receives data from M-Bus | Yellow (RX) |
| Pin 4 | DTR (data terminal ready) | unused | |
| Pin 5 | GND (signal ground) | GND | Black (GND) |
| Pin 6 | DSR (date set ready) | unused | |
| Pin 7 | RTS (request to send) | unused | |
| Pin 8 | CTS (clear to send) | unused | |
| Pin 9 | RI (ring indicator) | unused |
3.3 RS485 Interface
A 2-wire RS485 interface will be connected to the RS485 terminals (A = + and B = -). Please note that this is a transparent interface without addressing on the RS485 bus. The direction control of the half- duplex 2-wire connection is realized that the PW100 is passive in the idle state (receiver on, transmitter off) and becomes on transmitted data from M-Bus meters (receiver off, transmitter on). The level converter remains active on the RS485 for approximately 50ms after the last transmitted space (0-Bit) of the slave. The master software should not start a new request to the connected meters during this period.
The RS485 bus is not terminated in the PW100. If a termination is required, an appropriately dimensioned external resistor, e.g. 120Ω can be connected between terminals A + and B-.
3.4 Repeater Interface
The PW100 can be used as a so-called Repeater, as a network extension for existing M-Bus systems, if the maximum number of meters or the maximum cable length has been exceeded for the installation. Up to 100 devices and up to 4km cable (1 x 2 x 0.8 JYSTY) at 2400 baud transmission speed can be connected to a repeater. 
The M-Bus line of the existing master or level converter is connected to the terminals labelled with M-Bus Repeater. The polarity does not matter – as usable and standardized for M-Bus slaves. The signal at the M-Bus output of the PW100 is reconditioned to connect a complete M-Bus network. An almost unlimited number of repeaters can be cascaded or connected in parallel due to the automatic measurement of the maximum transmission speed and the recovery of bit times (bit recovery) by the digital repeater. This allows nearly unlimited M-Bus networks.
3.5 USB interface
The USB device port of the PW100 is as a USB 2.0 connector type B available on the front of the housing. Please use a USB cable with a type A plug on one end and a type B plug on the other side (not supplied) to connect a PC. You must install the software driver for the virtual COM port before you can use the USB interface. This simulates a serial port that you can use as usual in your M-Bus software. You can find the driver on our CD “Tools & Docs”, on our homepage www.relay.de or directly from FTDI Chip, the manufacturer of the used USB chip: https://ftdichip.com/drivers/vcp-drivers (here you will also find drivers for Linux and Mac OS). Please unpack the ZIP file after download. Install the drivers by clicking on the unzipped file in the File Explorer with the right mouse button and select the menu item “Run as administrator“ (example file name is: CDM212364_Setup.exe).
Now you can connect the PC. The USB driver for the PW100 is installed automatically and generates a new, virtual COM port. The new COM port number of the USB serial port is displayed after the installation is finished (here: COM29). You can look up this number at any time in the Device Manager under ports (USB Serial Port) and – if desired – change it in the advanced settings of the driver. Please select the appropriate comport number in your M-Bus software.
3.6 Ethernet interface
The Ethernet interface of the PW100 converts the physical interface Ethernet 10/100BaseT to M-Bus and the TCP / IP protocol to the serial protocol. The Ethernet interface is available in the front panel as an 8-pin RJ45 socket. The PW100 can be integrated into an existing local network and the M-Bus meters can be read from one or more PCs in that network. This requires the so-called “Tibbo Device Server Toolkit” to be installed on that PC. With this software the Ethernet interface is configured in the PW100 and a virtual COM port is set up. This simulated serial interface enables the use of the usual M-Bus software designed for normal serial interfaces. Please perform the following steps of installation:
3.6.1 IT preparations
The IT division of the network containing the PW100 must define the following items:
- Fixed IP address must be identical to the IP range of the reading computer. Only the last number must be different. (e.g. 192.168.1.239)
- You need also the subnet mask and IP address of the gateway if the IP addresses are reassigned by a gateway.
- The converter uses the port 1001 by default for the TCP protocol. This port must not be blocked by any firewall.
You can find your own IP address in your network this way:
3.6.2 Software installation
You can find the driver software on our CD “Tools&Docs”, on our homepage www.relay.de or directly at the manufacturer´s site: https://tibbo.com/support/downloads/tdst.html. Please start depending on your operating system either the 32 bit or 64 bit version of the installation program as an administrator: tdst_5-14-00-x86.exe (32-Bit Windows) or tdst_5-14-00-x64.exe (64-Bit Windows) TDST = Tibbo Device Server Toolkit, 5-14-00 = Version 5.14.00 dated August 2021
After a reboot of the PC the installation of the drivers and software tools is completed.
3.6.3 Setup of the device server
Please start the Tibbo – DS Manager (Start – Programs – Tibbo – Tibbo Device Server Toolkit – Tibbo DS Manager.
The DS Manager (DS = Device Server) shows all by broadcast detectable device servers in the sheet „Auto Discovery“. Device servers which are not in the same IP address range will not be found and must be manually added into the sheet “Address Book” (button “Add”). Please select the device which you want to configure and click on the button “Settings”. Then you see the settings of the device which you shall change according to the following pictures. You can get help for the DS Manager with F1 key.
Recommended settings:
3.6.4 Setup of the virtual port
The next step is the setup of a virtual, serial port in your PC. You don´t need the virtual port if the used software offers a TCP/IP port instead of serial ports. In this case you must correctly program all settings of the serial interface like baudrate, parity and data bits. You also don´t need a virtual port in the bridge mode (two device servers connected together, i.e. one TCP001 (serial device server) to the PW100.
Please start the Tibbo – DS Manager (Start – Programs – Tibbo – Tibbo Device Server Toolkit – Tibbo VSP Manager.
Please add a VSP (virtual serial port) by clicking on the “ADD” button.
Please do the following settings:
Then you can program the values for the serial communication after startup in the sheet “Default Serial Settings” (baudrate, data bits, parity, flow control). A click at „OK“ generates the virtual port and then it can be used in your M-Bus software. Please select the respective port (VSP name) in your software as the communication interface. Now the installation is completed. You can change the settings of the device and the COM port using the DS manager respectively the VSP manager at any time. You can also change the settings of the device server and check its routing state after first setup using a web browser connected to the assigned IP address. The required password for the login is empty on delivery.
Technical data
4.1 General data
| Operating voltage | 42,0 .. 43,5 VDC |
| Power consumption | max. 15W |
| Operating temperature range | 0 .. 50°C |
| M-Bus voltage | 42 V ( Mark), 28V (Space) |
| M-Bus basic current | max. 150 mA |
| Overcurrent threshold | > 220 mA |
| Internal bus resistance | 5 Ohm |
| Communication speeds | 300 .. 38400 Baud |
| Bit threshold | typ. 7,0 mA |
| Collision threshold | typ. 48 mA |
| Maximum cable length for recommended cable type JYSTY 1x2x0,8mm | Total (all wires): 1km (9600 baud), 4km (2400 baud), 10km (300 baud) Max. distance to slave (100 slaves at the end of the cable):1000 m Max. distance to slave (100 slaves equally distributed): 2000 m |
| Galvanic isolation | All interface are isolated from M-Bus and power supply. The Repeater input is additionally isolated from the other interfaces. |
| Housing | Light-grey and black PC plastic, protective class IP30 H x W x D: 90 x 107 x 60 mm (height without terminals) Mounting on a rail (6 HP) |
| LED indicators | Power, communication master, slave, warning, short circuit M-Bus, M-Bus activity |
| Interfaces | 10/100 Mbit Ethernet, USB device, 2 x RS232C (terminals), RS485, Repeater |
| Terminals | 3 pairs screw terminals for M-Bus, 3-pin screw terminal for each RS232C, 3-pin screw terminals for RS485, one pair screw terminals for Repeater, 3-pin screw terminals for power supply / protective ground |
4.2 Interface data
| RS232C | Driver load | Current max. 5mA, resistive: min. 3kΩ, capacity: max. 2,5 nF |
| Voltage transmit (at 3kΩ) | Mark: +5V ≤ UT ≤ +15V Space: -15V ≤ UT ≤ -5V |
|
| Voltage receive | Mark: +2,5V ≤ UR ≤ +15V Space: -15V ≤ UR ≤ -2,5V |
|
| RS485 | Driver load | Current max. 250 mA, resistance min. 54Ω |
| Signal voltage TX | Space (0): +1.5V £ Ut £ +5.0V Mark (1): -5.0V £ U £ -1.5V |
|
| Addressing | Not possible (transparent) | |
| Max. cable length | 3,0 m | |
| Repeater | Current M-Bus IN | Basic current < 1,5 mA (1 Unit Load), TX current typ. 15mA |
| Capacity | Max. 250 pF | |
| Galvanic isolation | > 2,5 kV to all interfaces, M-Bus and power supply | |
| USB | Type | USB 2.0 device, socket type B |
| USB IC | FTDI Chip: FT232R, Vendor ID = 0403, Product ID = 6001 | |
| Power supply | Bus powered, Low Power (max. 90mA) | |
| Max. cable length | 3,0 m | |
| Ethernet | Network interface | 10/100BaseT (RJ45), auto-MDIX, with 2 LEDs |
| Protocols / adressing | TCP and UDP / static IP or dynamic IP (DHCP) |
4.3 Ordering information
| Article number | Description |
| PW100 | M-Bus Level Converter and Repeater for 100 slaves |
| NT016 | Power supply 42VDC, 30W, rail, input range 85 .. 264 VAC, 47 .. 63 Hz |
| KA USB AB | USB cable A to B plug/plug, length = 1m, grey |
| KA PATCH.5E RJ45 1M | Network patch cable CAT5E FTP, Length = 1m, grey |
| KA006 | Serial D-SUB-9 female cable with 3 open wires |
PW100
User Manual
Version 1.1
11/2023
Documents / Resources
 |
Relay PW100 M-Bus Level Converter [pdf] User Manual PW100, PW100 M-Bus Level Converter, M-Bus Level Converter, Level Converter, Converter |