Hello all.
I'm trying to control a heater with a S7-1200 CPU with the CM1243 communications processor. The two devices are connected with a null modem cable. So far all my efforts to send commands to the heater were not successful. So now I'm thinking that the data that I send to the heater isn't correct. The heater's manual describes the commands likeso:
A transfer sequence consists of:
• command
• space (⇔; Hex: 20)
• parameter (the character separating decimals in a group is
the period)
• end of file (↵; Hex: 0D)
The commands are divided into in or out commands.
in commands: asking for parameters to be displayed
out commands: setting parameters
The out commands are valid only in remote control mode.
Command to set the working temperature > SETP 1< to 55.5 °C
out_sp_00 ⇔ 55.5↵
Command to ask for the working temperature > SETP 1<
in_sp_00↵
Response from the circulator:
55.5↵
So i have tried to send the command for the working temperature, but there is no response from the heater.
I send the data as an struct of characters with the Send PTP block. But I am not shure that this is correct, because I don't know what the symbol at the end is. I have even tried converting the hex value stated above (0D) to a string and put it at the end but it doesn't work. I've also tried to send a complete HEX value to the heater but again there is no reply. I have also tried to send these commands with a hyper terminal and a RS232 analyzer but it is the same. I have run out of ideas now, so any help on this topic would be great.
I've also checked if I get any data on the heaters connector with a RS232 analyzer, and the data is equal to what I send with in the PLC. So now I'm out of ideas.
Any ideas folks?
Cheers.
I'm trying to control a heater with a S7-1200 CPU with the CM1243 communications processor. The two devices are connected with a null modem cable. So far all my efforts to send commands to the heater were not successful. So now I'm thinking that the data that I send to the heater isn't correct. The heater's manual describes the commands likeso:
A transfer sequence consists of:
• command
• space (⇔; Hex: 20)
• parameter (the character separating decimals in a group is
the period)
• end of file (↵; Hex: 0D)
The commands are divided into in or out commands.
in commands: asking for parameters to be displayed
out commands: setting parameters
The out commands are valid only in remote control mode.
Command to set the working temperature > SETP 1< to 55.5 °C
out_sp_00 ⇔ 55.5↵
Command to ask for the working temperature > SETP 1<
in_sp_00↵
Response from the circulator:
55.5↵
So i have tried to send the command for the working temperature, but there is no response from the heater.
I send the data as an struct of characters with the Send PTP block. But I am not shure that this is correct, because I don't know what the symbol at the end is. I have even tried converting the hex value stated above (0D) to a string and put it at the end but it doesn't work. I've also tried to send a complete HEX value to the heater but again there is no reply. I have also tried to send these commands with a hyper terminal and a RS232 analyzer but it is the same. I have run out of ideas now, so any help on this topic would be great.
I've also checked if I get any data on the heaters connector with a RS232 analyzer, and the data is equal to what I send with in the PLC. So now I'm out of ideas.
Any ideas folks?
Cheers.