CP1H has a feature called Modbus Easy Master Function, which makes it easy to communicate to modbus units like inverters, tempcontrollers etc.

No need to calculate CRC-16 check sum, just enter the relevant command parameters in a pre-defined Data area, and activate a start-bit.

In this example we use:

CP1H-XA40DR-A with CP1W-CIF01 RS232-Option board
CJ1W-CIF11 RS232-C/RS485 converter
(Alternatively use only CP1W-CIF11, RS485 Option board)

E5CN-Q2MT-500 Tempcontroller

Switch settings:
CIF11: 4 & 5 OFF, all the rest ON.

Wiring:
CIF11 <--------------------------> E5CN
Plint 3=SDA- connected to terminal 12=A-
Plint 4=SDB+ connected to terminal 11=B+

Temp controller settings:
Select Modbus communication Mode, Unit 1, Baud rate 9600, Send Wait 20ms

PLC settings (in CX-One)

Set the following values in D-area

D32200 = 0001 (unit number 1)
D32201 = 0003 (Function code "Read Variable)
D32202 = 0004 (Number of bytes in command string)
D32203 = 0000 (Variable start adress for Present Value)
D32204 = 0002 (Number of elements to Read, Minimum 2)

Set the send bit A640.00 to On

Response can be read in D32250 and onwards

Related Manuals:
H135-E1-01B or later, E5CN/AN/EN Communications manual
W450-E1-02 or later, CP1H Operation manual