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Serial Communications in Industrial Automation

RS232 and RS485 Serial Communication is,  and will remain widely used in Industry for PLC, RTU and Smart Instrumentation connectivity.

RS232 Connectivity for Device Configuration and Maintenance

RS232 connectivity has been used to configure and maintain intellgent devices. Even on IP devices a RS232 serial port (console port) is commonly used to set the IP address parameters include IP Address, Netmask, and Default Gateway.

Sometimes newer network devices did not have serial port in the goal of cost and power savings. Invariably you would lose the IP address or set it was wrong. Then you have to reset it to factory defaults so you could communicate to it again.  A RS232 console port would have been more convenient!  USB Ports have often been provided as a console ports.

On devices with RS232 console ports it often convenient to have both local or remote connectivity since the console port may have diagnotics function not available via other interfaces. Remote RS232 console port connectivity can be achieve by connecting console port to a terminal server such as the SCADALink IP100 Industrial Terminal Server.

RS485 Network for Device Connectivity.

RS485 has been used for multidropped network connectivity for PLC, RTU, and Instruments and will remain so for the future. Devices in SCADA & OT networks are networked with RS485 due to low cost, low power draw, and freedom from IP security concerns.  In addition smart instruments with Modbus RS485 can provide more diagnostic and analytics information that simple 4-20ma instrument.

The SCADALink A485 4-20ma to Modbus Converter has been designed to enable 4-20ma  instruments to be connected via Modbus RS485 where there limited I/O. The A485 can also provided additional parameter include min,max, and average readings in addition to instantaneous reading.

Laptops Without Serial Ports

Moderm laptops are now commonly manufactured without serial port as most people don’t need them or use them whereas it is deRigeur for Industrial Automation Geeks.

SCADALink USC USB to Serial Converters with RS232/RS485 is designed to provide easy connectivity to Industrial Devices requiring RS232/RS485 Serial Connectivity.