Function Introduction:
The WJ71 remote I/O module can be used to measure four switch signals and has four relay signal outputs.
1,Switching signal input and output
Three channel switch signal input, capable of connecting dry contacts and wet contacts. Please refer to the wiring
diagram for details; Ten relay normally open contact output.
2,Communication Protocol
Communication interface: 1 standard RS-485 communication interface or 1 standard RS-232 communication
interface, please specify when ordering and selecting.
Communication Protocol: Supports two protocols, the character protocol defined by the command set and the
MODBUSRTUcommunication protocol. The module automatically recognizes communication
protocols and can achieve network communication with various brands of PLCs, RTUs, or computer
monitoring systems.
Data format: 10 digits. 1 start bit, 8 data bits, and 1 stop bit.
The communication address (0-255) and baud rate (2400, 4800, 9600, 19200, 38400, 57600, 115200bps) can be set;
The communication network can reach a maximum distance of 1200 meters and is connected through
twisted pair shielded cables.
High anti-interference design of communication interface, ± 15KV ESD protection, communication response time
less than 100mS.
3,anti-interference
Checksums can be set as needed. There is a transient suppression diode inside the module, which can effectively
suppress various surge pulses and protect the module
Product Overview:
The WJ71 product realizes signal acquisition and control between sensors and hosts, used to detect switch signals or
control device operation. The WJ71 series products can be applied in industrial automation control systems with
RS-232/485 bus, measurement and control of switch signals, measurement and output of high and low level signals, as
well as industrial field signal isolation and long-distance transmission, etc.
The product includes power conditioning, switch quantity acquisition, relay output, and RS-485 serial
communication. Each serial port can connect up to 255 WJ71 series modules, and the communication method adopts
ASCII code communication protocol or MODBUS RTU communication protocol. The baud rate can be set by code and
can be hung on the same RS-485 bus as control modules from other manufacturers, making it easy for computer
programming.
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