C2285 industrial RS232/RS422-485 communication converter with optoelectronic isolation input, independent internal power supply, power supply and transmission/reception indication, RS485 zero waiting time, RS232 fault indication
MAXIM's latest driver, signal source detection function, DIN rail or screw installation

1、 Main technical indicators:

Isolation voltage between input/output:>2000VDC Use baud rate: 600-19200 BPS
RS-232C: TXD, RXD, GND three wire system
RS422: SD+, SD -, RD+, RD - four wire system full-duplex
RS485: TR+, TR - two-wire system Half-duplex
Function and RS485 baud rate setting: internal DIP switch selection
485 communication format: Data bits: 7 or 8 bits; Stop position: 1 or 2 positions; Parity bit: 1 bit or none
Accessible load: MAXIM 1/8 unit load ＜ 256 (usually 32, depending on the visual communication speed and line quality)
Indication: Red LED RS232 data transmission and power indicator, green LED data reception
Power supply: 220V AC 3W without built-in fuse

System wiring:
1. 422 interface connection: Note: Set the SW1 switch to 110, and open the JI and J2 on the circuit board
2.485 Interface Connection Form: Note: JI and J2 on the circuit board need to be short circuited

3、 Baud rate setting for two-wire half duplex RS485 transmitter/receiver converter
The conversion of RS485 transmission/reception bus is completed by an internal intelligent controller, which can automatically determine the direction of data flow. When in master-slave state, once data is received from the upper computer, it is immediately forwarded to the lower computer; After forwarding is completed, the data from the lower computer will be automatically transferred to the upper computer. Please refer to the label on the panel for baud rate selection. Note: The baud rate of the RS485 converter must be consistent with the communication baud rate of the system.

4： Self testing and signal source
Set the SW1 switch to 111 and complete the following functions
1. Self testing RS485 test result: All transmit and receive lights are on
2. Self testing RS422 test result: All transmitting and receiving lights are on
1 RXD data receiving data sending high SD+4
2 TXD data transmission data transmission low SD -5
3 GND signal ground data receiving high RD+6
Data reception low RD-7

3. 2KC pulse signal
When using multiple devices for long-distance transmission, it is necessary to adjust the matching resistance of the receiving terminal (inside the instrument). Using a 2KC pulse signal, adjust the resistance value to make the pulse waveform observed on the oscilloscope as consistent as possible with the signal source waveform, achieving optimal impedance matching (maximum transmission). Note: For details, please refer to the pulse measurement method of the oscilloscope.

5、 Indicator lights and common troubleshooting
After power on, if 1) the upper computer is not powered on or 2) the RS232 connection is incorrect, the red LED will automatically flash for ten seconds and then turn off.
conversely. The red LED is on. Explanation: The upper computer is powered on, the RS232 connection is correct, and the controller power supply is normal.
When sending via RS232 on the upper computer, the input red LED flashes. When the lower computer returns data, the green LED light flashes. The baud rate of the RS485 converter must be consistent with the communication baud rate.

6： Ordering Notice: The RS422 or RS485 conversion type must be declared and distinguished by the RS422 or RS485 symbol on the label

7： DIN rail or screw installation dimensions: