5.6. RS485 Module
RS485 main control chip: SP491EEN, PIN 9, 10 were TX +,TX-,the
difference voltage close to 5 V
TVS: B03NC (BA5/6/7/8), HK-4 (D2/3/4/5) protect the sending end (TX +,
TX-R +, R-)
Thermistors (JK250) : JK250 (RPT1/2/3/4) protect the sending end (TX +,
TX-R +, R-)
RS485 module part: