USB RS422 Converter – BFM/1
BFM/1 is a USB RS422 converter, self-powered at 5 V via the USB port. It can be used to enable a PC to communicate with an RS422 bus device or network. The converter is equipped with removable terminals and is powered via the USB port, so there is no need for an external power supply, and installation is very simple.
It is completely protocol-transparent, so it can be used with Modbus or any proprietary protocol that operates on an RS422 bus.
The USB RS422 converter appears on the PC as a virtual RS232 port (VCP, Virtual COM Port) and can be used by any program installed on the PC. The USB RS422 serial adapter operates in full-duplex mode and automatically detects baud rates up to 250 kbps, so it can be easily installed in any new or existing system.
The operating system usually recognizes the device and automatically installs the necessary drivers; if not, the drivers can be downloaded from this link.
Description
BFM/1 is a USB RS422 converter, self-powered via the USB port at 5 V. It can be used to enable communication between a PC and an RS422 serial bus. The converter is equipped with removable terminals and is powered via the USB port, so there is no need for an external power supply, so installation is very simple.
The operating system usually recognizes the device and automatically installs the necessary drivers; if not, the drivers can be downloaded from this link. The USB RS422 converter appears on the PC as a virtual RS232 port (VCP, Virtual COM Port) and can be used by any program installed on the PC. The USB RS422 converter operates in full-duplex mode and automatically baud rates up to 250 kbps, so it can be easily installed in any new or existing system.
When is a USB RS422 converter needed?
A USB RS422 converter is typically used to enable a PC to communicate with an RS422 serial network, or to program a device via the RS422 bus.
In a network with heavy electromagnetic interference, which is common in industrial environments, it is good practice to install two or more optical-to-electrical converters to ensure signal integrity. There are also environments where electrical equipment is prohibited, such as swimming pools, saunas, and buildings at risk of fire, where fiber optics therefore become necessary.
Modbus and other protocols
BMM/1 USB RS422 converter is completely protocol-independent. This means that the converter is transparent to the communication and can be used with protocols such as Modbus, BACnet, or any proprietary protocol.
This is possible because the converter operates at the logic level rather than at the protocol level. Therefore, this USB RS422 converter can also be used in complex networks where multiple protocols are present simultaneously on the same RS422 bus.
Ease of installation
The removable terminals make installation and replacement extremely easy.
With a modern operating system, USB drivers are usually installed automatically once the device is connected to the PC. From a software perspective, therefore, this USB RS422 converter is fully Plug & Play. If the PC is unable to communicate with the device, it is often sufficient to install the drivers manually, but we are, of course, available to provide support for resolving configuration issues.
Versatility
This USB RS422 converter is also available with other combinations of serial standards, or with different connectors. BFC/1 converter for example uses 5-pin Mini XLR connector, for non-isolated RS422. BTS/1 and BTV/1 feature synthetic or glass fiber optic connectors to provide additional isolation from electromagnetic interference.
BMM/1 and BMC/1 industrial serial converters operate with the RS485 standard, featuring either removable terminals or 5-pin Mini XLR connectors. All combinations of serial standards, fiber optics, and power supply options are available in the catalog; however, special requests (such as higher data rates) can be made via the contact form.
Technical Specifications
Main features
| Power supply | USB |
|---|---|
| Power consumption | 1 W |
| Serial transmission data rate | 0 – 250 kbps (automatic) – higher data rates on request |
USB
| Connector | USB type A |
|---|---|
| Technology | USB 2.0, USB 1.1 |
| Interface type | VCP (Virtual COM Port) based on RS232 |
| Data direction | Full Duplex |
| Supported operating systems | Windows 98 and above, Mac OS 8 and above, Linux |
RS422
| Communication type | Full Duplex on a balanced line |
|---|---|
| Maximum bus voltage | ± 60 V – ESD ± 16.5 kV (Human Body Model) |
| Common mode range | ± 25 V DC |
| Slew rate | Limited, to have an error-free transmission |
Mechanical features
| Dimensions | 90 mm x 50 mm x 25 mm |
|---|
Working conditions
| Degree of protection | IP20 |
|---|---|
| Operating temperature | -20 °C to +50 °C |
| Storage temperature | -40 °C to +80 °C |
