MELSEC-L Series Serial Communication Unit
Mitsubishi light & flexible sequencer.
[Features]
· Capable of non-procedural protocol communications by transmitting/receiving data based on the communication protocol specified by the external devices.
· Can connect to a device simply by selecting the device from the communication protocol library.
· Creating and editing communication protocols are easy, too.
[Applications]
· For reading/writing of the data on the sequencer from the external device.
Serial Communication Unit Features
Immediate Connection for Communication With Desired Device
All you have to do is to select any device you want to communicate with from the GX Works2 communication protocol library, and you can connect to the device immediately.
1. Select the manufacturer and model (series) of the connecting device: No need to set a complex communication protocol with the connecting device. Just select from the pre-prepared communication protocol library.
Communication protocol library
2. Write a communication protocol to the unit: Write a pre-defined communication protocol to the serial communication unit. Up to 128 settings can be made per unit.
Image of writing a communication protocol
3. Execute the protocol from the ladder program: Via the ladder program you can communicate with external devices simply by executing the dedicated command for starting the communication protocol.
Image of executing the dedicated command
Easy to Create and Edit Communication Protocols
Even when a desired device is not found in the communication protocol library, an additional communication protocol can be created in easy steps.
Image of creating a communication protocol
The content of the created communication protocol can be displayed in a list and can be edited easily.
Image of editing
Serial Communication Unit Specifications
| Item | LJ71C24 | LJ71C24-R2 | |
|---|---|---|---|
| Interface | ch1 | RS-232 compliant (D-Sub 9P female) | RS-232 compliant (D-Sub 9P female) |
| ch2 | RS-422/485-compliant (2-piece terminal block) | RS-232 compliant (D-Sub 9P female) | |
| Communication method | Circuit | Full-duplex / half-duplex | |
| MC protocol | Half-duplex | ||
| Communication protocol | Full-duplex / half-duplex | ||
| Non-procedural protocol | |||
| Bidirectional protocol | |||
| Synchronization method | Asynchronous method | ||
| Transmission speed | 50 bps / 300 bps / 600 bps / 1,200 bps / 2,400 bps / 4,800 bps / 9,600 bps / 14.4 kbps / 19.2 kbps / 28.8 kbps / 38.4 kbps / 57.6 kbps / 115.2 kbps / 230.4 kbps 230.4 kbps can be used on the ch1 side only. (Cannot be used on the ch2 side) The total transmission speed of the two interfaces may be used within 230.4 kbps. If the send/receive data monitoring function is used, the total transmission speed of the two interfaces may be used within 115.2 kbps. | ||
| Data format | Start bit | 1 | |
| Data bit | 7 or 8 | ||
| Parity bit | 1 (vertical parity) / None | ||
| Stop bit | 1 or 2 | ||
| Access cycle | MC protocol | One request is processed during END processing of the CPU unit for the C24 installed station. (The number of scans / link scans required for this process varies depending on the specific request.) | |
| Communication protocol | In both send and receive operations, this request is processed when the dedicated command (CPRTCL command) is executed. | ||
| Non-procedural protocol | Data is sent every time a send request is made, while reception of data can be made at all times. | ||
| Bidirectional protocol | |||
| Error detection | Parity check | Applicable to all protocols. If applicable, select odd or even using parameters. | |
| Checksum code | For MC protocol or bidirectional protocol, select by parameter. For communication protocol, whether or not a checksum code is available is determined by the selected protocol. In the case of a non-procedural protocol, a checksum code is selected by a user-registered frame. | ||
| Transmission distance (total extension distance) | RS-232 | Maximum 15 m | |
| RS-422/485 | Maximum 1,200 m (total extension distance) | - | |
| Number of units occupied | 1 | ||
| Number of occupied inputs/outputs | 32 points (I/O assignment: Intelligent 32 points) | ||
| 5 V DC internal current consumption | 0.39 A | 0.26 A | |
| Weight | 0.17 kg | 0.14 kg | |
Transmission Control
| RS-232 | RS-422/485 | |
|---|---|---|
| DTR/DSR (ER/DR) control | Available | Not available |
| RS/CS control | Available | Not available |
| CD signal control | Available | Not available |
| DC1/DC3 (Xon/Xoff) control DC2/DC4 control | Available | Available |
- DTR/DSR signal control and DC code control can be selected.