Hi, thanks for regard.

I want to communicate with a equipment of Induction through rs485 serial. I don't know the protocol of comunicacion, i think that is ASCII not MOTBUS RTU, but i not sure.

i can comunicate through hyperterminal with the equitment​ but i can`t do it with the PLC.

AMBRELL EASY HEAT (Induction equitment):

​38400 Baud
8 data bits
parity none
stop bits 1
flow control None

COMMAND SET:

adrress,command,argument

for example: 1,amps,20

Rmaeso

Hi, thanks for regard.

I want to communicate with a equipment of Induction through rs485 serial. I don't know the protocol of comunicacion, i think that is ASCII not MOTBUS RTU, but i not sure.

i can comunicate through hyperterminal with the equitment​ but i can`t do it with the PLC.

AMBRELL EASY HEAT (Induction equitment):

​38400 Baud
8 data bits
parity none
stop bits 1
flow control None

COMMAND SET:

adrress,command,argument

for example: 1,amps,20

Using Hyperterminal confirms it is ASCII communication. 

I would suggest that the MOVE instruction have "Send_P2P_DB".Status connected on the IN pin. Then %MW12 will store the error state if it comes up.

There are some questions that needs answering. But you can place the engineering project here as a ZIP file for further study and avoid answering the questions.

Thank you for your answer.

I attach the zip file with the project

regards

1. The CM1241 can only handle 2 wire RS485. Make sure that the induction heater is wired like that and set in its configuration to 2 wire instead of 4 wire. See the "communication" menu option on the heater.
   
   
2. Some times the RS485 wires needs to be swapped. (This depends on which IC manufacturer's wiring diagram was used.)
   
   
3. It is better to have the Port_Config instruction included in the PLC program. Yes, even if it is only a repeat of the hardware configuration. The instruction should initialize the port for use.
   
   
4. It is best to fill out the actual length of characters being transmitted in the P2P_Send instruction. 
   
   
5. Check if Hyperterminal is sending out line return character(s). This is not documented in the heater manual but might be needed. You could ask the supplier also to make sure.

Feel welcome to return with your feedback. A communications expert ^{(shoutout to friend Ivan)} may have more to add when you have a response to give.

Good luck.

Thanks for de answers.

Finally, i found the problem. The problem was in how received and sended the buffer.

when i sended the command set, i didn't send [CR/LF] in the end of my command set:

CR ==> 16#d pointer return

LF ==> 16#a line break

for example:

My command set ==>1,ampsCRLF

16#31

16#2C

16#61

16#6D

16#70

16#73

16#d

16#a

i also had to define in HW the end of the command set.