GUILCOR AR006683, Instruction Manual

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6.1. Modbus RTU
Control units communicate on master-slave principle in half-duplex operation. Only master can
send request and only addressed device responds. During sending of request no other slave station
should respond. During communication, data transfer proceeds in binary format. Each Byte is sent as
eight bit data word in format: 1 start bit, data word 8 bit (LSB first), 2 stop bits 1 , without parity.
Device supports communication speed from 110Bd to 115200Bd.
Sent request and response have syntax: ADDRESS OF DEVICE – FUNCTION – Modbus CRC
6.1.1. Supported functions
03 (0x03) : Reading of 16-bit registers (Read Holding Registers)
04 (0x04) : Reading of 16-bit input gates (Read Input Registers)
06 (0x06): Setting of one 16-bit register (Write Register)
16 (0x10)
: Setting of more 16-bit registers (Write Multiple Registers)
6.1.2. Jumper
Jumper (placed nearby keys) is accessible after demounting of four screws in the corners of the
box and removing the lid. If communication protocol Modbus is selected the function of jumper is
as follows:
 Jumper opened – device memory is protected from writing, from device side it is only enabled
to read measured value, writing to memory is disabled (no change of settings is enabled)

Jumper closed – writing to regulator memory is enabled
6.1.3. Modbus registers of the regulator
Variable Unit
Address
[hex]
X
Address
[dec]
X
Format Size Status
measured temperature [°C/°F]* 0x0031 49 Int*10 BIN16 R
measured relative humidity [%] 0x0032 50 Int*10 BIN16 R
computed value* 0x0033 51 Int*10 BIN16 R
Relay1 status [0/1] (Alarm 1) [-] 0x003B 59 Int BIN16 R
Relay2 status [0/1](Alarm 2) [-] 0x003C 60 Int BIN16 R
binary input 1 status [0/1] [-] 0x003D 61 Int BIN16 R
binary input 2 status [0/1] [-] 0x003E 62 Int BIN16 R
binary input 3 status [0/1] [-] 0x003F 63 Int BIN16 R
status of all binary inputs
(bit0, 1, 2)
[-] 0x0008 8 Int BIN16 R
status word (described below) [-] 0x0007 7 Int BIN16 R
device serial number Hi [-] 0x1035 4149 BCD BIN16 R
device serial number Lo [-] 0x1036 4150 BCD BIN16 R
firmware version Hi [-] 0x3001 12289 BCD BIN16 R
firmware version Lo [-] 0x3002 12290 BCD BIN16 R
device address [-] 0x2001 8193 Int BIN16 R/W**
communication speed code [-] 0x2002 8194 Int BIN16 R/W**
1
Device sends two stop bits, for receive one stop bit is enough.