Industrial USB to 4-Channel RS485 Converter

This 4-Channel RS485 converter extends USB connectivity to four independent RS485 channels, allowing concurrent communication for each. It has multiple protection features to provide reliability in demanding projects. It is equipped with an onboard Transient Voltage Suppressor (TVS) that provides a defence against surge voltages and transient spike voltages, making it both lightning-proof and anti-electrostatic.

Safety measures include resettable fuses and protection diodes that stabilise current and voltage outputs, providing resistance against over-current and over-voltage conditions, and enhancing shockproof performance. The converter features an onboard RS485 output terminal with 120R resistors, which can be enabled or disabled via a DIP switch to suit various application needs.

Note: It is not possible to control all four RS485 using only one ComPort

Features

• Extending USB to 4CH RS485, allows concurrent and independent communication for each channel
• TVS (Transient Voltage Suppressor), suppress surge voltage and transient spike voltage in the circuit, lightning-proof & anti-electrostatic
• Resettable fuse and protection diodes, provide the current/voltage stable outputs, provide over-current/over-voltage proof, improve shockproof performance
• Onboard RS485 output terminal 120R resistors, enabled/disabled via DIP switch
• Aluminium alloy case with oxidation dull-polish surface, CNC process opening, solid and durable, well-crafted

Specifications

Host Port	USB
Device Port	RS485
Baudrate	1200bps ~ 460800bps
USB	Operating voltage	5V
	Connector	USB-B
	Protection	500mA resettable fuse, ESD protection
	Transmission distance	About 5m
RS485	Connector	Screw Terminal
	Protection	600W lightning proof and surge-suppress, 15KV ESD protection
	Transmission distance	Maximum communication distance is about 1200m (at a low rate, with 120R resistor turned on)
	Transmission mode	Point-to-multipoints (up to 32 nodes, it is recommended to use repeaters for 16 nodes or more)
Operating Environment	Temperature	-40 ~ 85℃
	Humidity	5%RH ~ 95%RH
Operating System	Win7/8/8.1/10/11, Mac, Linux, Android

Resources

• Product Wiki
• CH344 Datasheet

Pinout

PWR	The power indicator, lights up while the USB is connected and voltage is detected
ACT	Status indicator lights up green while the driver is detected.
RXD(1~4)	Blue RXD indicators, light up when the device ports send data back
	(corresponding to 4 channels respectively)
TXD(1~4)	Blue TXD indicators, light up when the USB port is sending data
	(corresponding to 4 channels respectively)

PE	Signal ground
A(1~4)	A(1~4) differential signal A+
B(1~4)	B(1~4) differential signal B-

Package Contents

• 1x USB TO 4-CH RS485 Converter
• 1x USB type A to type B cable ~1.2m