Is it necessary to add an RS232 opto-isolator to connect a serial electronic scale to a computer? Also, how many meters can the serial cable be extended without affecting the signal?

The computer comes with a serial port that is easy to burn out and cannot be plugged or unplugged with electricity!

You can consider adding RS232 optoisolator

General RS232 transmission of about 20 meters

Extension, depending on what measures to take

Please see the Wuhan Hongwei Optoelectronics

E232Y RS-232 passive isolation of the remote transceiver

Features

As much as 95% of the serial port stealing power technology. No external power supply

Current loop transmission, support TX, RX, GND three-wire serial port

Signal isolation, transparent transmission, baud rate adaptive, no need to change the user agreement

Built-in 600W/ms anti-lightning protection and 15KV electrostatic protection

Avoid loop voltage, surge, induced lightning, static electricity, hot plugging damage to the device

Communication distance Up to 3km

Suitable for computers with standard DB9 serial port

F201 RS-232/RS-485/422 Fiber Optic Converter

Features

RS-232/RS-485/422 converter, full-duplex, half-duplex communication

With integrated industrial terminals

Unique serial port protection circuitry, can be powered hot-swap

Built-in intelligent module, automatic identification of the circuit voltage. p> Built-in intelligent module, automatic identification of RS-485 signal flow, no need for CTS flow control

Built-in 600W/ms anti-lightning protection and 15KV anti-static protection

Transparent transmission, baud rate adaptive, no need to change the user agreement

Communication Distance Multi-mode (-P): 5km Single-mode (-S): 20km

Suitable for standard rs232 level Tx Rx Gnd 3-wire serial communication