RS232-RS485 mains converter – PRMP/1
PRMP/1 is a DIN-rail RS232-RS485 mains converter, powered directly by 230 V mains voltage.
It is completely protocol-transparent, so it can be used with any proprietary protocol that operates over RS232.
The RS232 serial port operates in full-duplex mode, while the RS485 serial port operates in half-duplex mode, with automatic data direction. The RS232-RS485 mains converter automatically detects baud rates up to 250 kbps, so it can be easily installed in any new or existing system. The device is fully Plug & Play and requires no drivers or DIP switches.
Description
PRMP/1 is a DIN-rail RS232-RS485 mains converter, powered directly by 230 V mains voltage. This industrial adapter can be used to enable communication between two devices that use different standards, or to extend the transmission distance of a serial communication. It can be mounted on a control panel with a 35 mm DIN rail and it’s very compact, as it occupies only 2 DIN modules. The device is fully Plug & Play and requires no drivers or DIP switches.
The RS232 serial port operates in full-duplex mode, while the RS485 serial port operates in half-duplex mode, with automatic data direction. The RS232-RS485 mains converter automatically detects baud rates up to 250 kbps, so it can be easily installed in any new or existing system.
Use cases
Serial converters are used to connect older equipment that uses RS232 to an RS485 bus. The RS232 standard is still widely used in industrial machinery, but it has a number of issues, including limited transmission distance and low noise immunity. RS485, on the other hand, is more robust, more resistant to interference, and generally more recommended and used for serial buses. RS485 is used above all in building automation, where the bus can extend over hundreds of meters.
Electromagnetic interference is common in industrial environments, so it is good practice to use a standard other than RS232 for serial communication, to ensure signal integrity. If it is necessary to isolate the communication to protect it from minor or moderate interference, an isolated converter such as PRLP/1 is recommended.
In case of heavier electromagnetic interference (EMI), optical fiber is recommended, as it also ensures perfect electrical isolation in case of adverse events such as power surges and lightning strikes. Optical fiber can be single-mode or multi-mode, plastic or glass. For transmission speeds up to a few Mbps, multi-mode synthetic optical fiber (POF) is sufficient: it is very easy to install and lay compared to glass fiber, for example, which requires specific tools for termination.
Protocol
PRMP/1 RS232-RS485 mains converter is completely protocol-independent. This means that the converter is transparent to the communication and can be used with any proprietary protocol.
This is possible because the converter operates at the logic level rather than at the protocol level. Therefore, this RS232-RS485 mains converter can be used with any computer or machine that communicates via a DB9 port using the RS232 serial standard.
Versatility
The RS232-RS485 mains converter is available with 400 V or 560 V isolation, with a low-voltage power supply, or with a DB9 connector for RS232. PRLP/1 converter, for example, features an isolated RS485 for protection against power surges. IMC/9R (isolated) and RMC/9R are much more compact and suited to a direct connection to a device with a DB9 connector.
PRM/1 industrial serial converter is functionally identical to PRMP/1 but operates at low voltage, as does PRL/1, which however is isolated. Other combinations of serial standards, optical fiber, and power supply are available in the catalog, while special requests (such as higher baud rates) can be made via the contact form.
Technical Specifications
Caratteristiche principali
| Alimentazione | 230 V AC 48/62 Hz |
|---|---|
| Assorbimento | 1 W |
| Velocità di trasmissione | 0 – 250 kbps (automatica) |
| Ritardo di propagazione | 600 ns (tipico) |
RS232
| Communication type | Full duplex |
|---|---|
| RX input voltage | 1.5 V low input threshold – 1.8 V high input threshold (± 25 V max) |
| TX output voltage | ± 5 V (± 5.4 V max) |
| ESD performance RX / TX | ± 15 kV (Human Body Model) – ± 8 kV IEC61000-4-2 contact discharge |
RS485
| Communication type | Half Duplex on a balanced line, with automatic data direction |
|---|---|
| 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
| DIN Rail | 2 modules |
|---|---|
| Dimensions | 90 mm x 36 mm x 57 mm |
| Weight | 83 g |
Working conditions
| Degree of protection | IP20 |
|---|---|
| Operating temperature | -20 °C to +50 °C |
| Storage temperature | -40 °C to +80 °C |
