Trox Technik EM-BAC-MOD-01, Руководство по настройке

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4.2 Modbus interface
Application
The expansion module EM-BAC-MOD supports the fol-
lowing Modbus interface functions in the Modbus pro-
tocol settings:

Modbus is an open serial master-slave communica-
tion protocol which has become a de facto standard
for the industry

The master (e.g. central BMS) can address a
number of slaves (EASYLAB volume flow control-
lers) and use Modbus functions to request informa-
tion from individual data points

Data access is based on numbered data registers
which the master has to define in order to request
data using Modbus functions

The slave responds by either returning the
requested information or an exception code (error)

Example: The
Read Holding Registers
func-
tion (register no. 3) returns the volume flow rate
actual value of the addressed controller
 General information for a Modbus device can be
read out using the
Read Device
Identifikation
function
Abbreviations
EASYLAB:
FH - Fume cupboard controller
RR - Room controller for supply air or extract air
(RS, RE, PC)
RR RMF - Room controller with active room manage-
ment function
EC, SC - Single controller for supply air or extract air
(EC, SC)
TAM - Adapter module
TAM
RMF
- Adapter module with active room manage-
ment function
WR - Defaults for the volume flow controller or
room, from the central BMS
RD - Data provided by the volume flow con-
troller or room
TROX UNIVERSAL CONTROLLER:
RS/RE - Volume flow controllers for supply or
extract air
RS/RE
RMF
- Volume flow controller with active room
management function
PR*/PD* - Room pressure controller or duct for
supply or extract air
PR*/PD*
RMF
- Room pressure controller or duct with
active room management function
Modbus functions
Function no. Designation Meaning
1 (0x01) Read Coils Read states of 1 to 8 bits according to bit list
3 (0x03) Read Holding Registers Read several consecutive registers
4 (0x04) Read Input Registers Read several consecutive registers
5 (0x05) Write Single Coil Write state of a single bit
6 (0x06) Write Single Register Write single register
8 (0x08) Diagnostics Check Modbus communication
16 (0x10) Write Multiple Registers Write several consecutive registers
43 (0x2B) Read Device Identification Read identification data for the device
14 (0x0E) Read Device Identification Read identification data for the device
Interface information
Modbus interface
Expansion module EM-BAC-MOD-01 16