Proline Kryomats
101 / 137
8.3.2
Protocol RS 232
The interface operates with one stop bit, no parity bit and 8 data bits.
Transfer rate either 2400, 4800, 9600 (factory setting) or 19200 baud as selected.
The RS 232 interface can be operated with or without hardware handshake, (RTS/CTS).
The command from the computer must be terminated with CR, CRLF, or LFCR.
The response of the thermostat is always terminated with CRLF.
After each command sent to the thermostat, it is necessary to wait for the reply before
sending another command. This ensures that the sequencing of inquiries and answers is clear.
CR = Carriage Return (Hex: 0D)
LF = Line Feed (Hex: 0A)
Example:
Transfer of setpoint 30.5 °C to the thermostat
Computer
Thermostat
“OUT_SP_00_30.5“CRLF
“OK“CRLF
8.3.3
Connecting cable RS 485
Thermostat
9-pin sub-D-socket
Pin
Data
1
Data A (-)
5
SG (Signal Ground)
optional
6
Data B (+)
Use screened connecting cables.
Connect screen to connector case.
The connections are galvanically isolated from the rest of the electronics.
Any pins not in use must not be connected!
An RS 485 bus always requires bus termination in the form of a termination network, which ensures a
defined rest
status in the high-resistance phases of bus operation. The bus termination is as follows:
