16
Secondary addressing
In addition to primary addressing, the EE77x transmitter provides the option of secondary addressing. The
fields of identification number, manufacturer, version and medium are used together as the secondary
address. The exact sequence of the secondary addressing is described in detail in the M-Bus Standard: http://
www.m-bus.com/files/MBDOC48.PDF.
4.2.2. Modbus RTU
The measured values are stored as a 32Bit float value. Depending on the measurement unit selected, the
measurements are saved in SI or US/GB units. The measurement unit can be changed using the configuration
software.
For resetting the MIN/MAX-Values write 0 to the corresponding write register.
For Modbus protocol setting please see Application Note AN0103 (www.epluse.com/EE776).
Modbus Map:
Register
Protocol-
Address
Measuring Value
SI-Unit
US/GB-Unit
Read Registers (Function Code 0x03 / 0x04) / 32Bit float Value
30026
19
Standardized Flow
Nm/s
SFPM
30028
1B
Standardized Volumetric Flow
Nm
3
/h
SCFPM
30030
1D
Temperature
°C
°F
30032
1F
Massflow
kg/h
kg/h
30034
21
Consumption reading
m
3
ft
3
30036
23
Pressure
bar
psi
30261
104
MIN-Value Standardized Flow
Nm/s
SFPM
30263
106
MAX-Value Standardized Flow
Nm/s
SFPM
30265
108
MIN-Value Standardized Volumetric Flow
Nm
3
/h
SCFPM
30267
10A
MAX-Value Standardized Volumetric Flow
Nm
3
/h
SCFPM
30269
10C
MIN-Value Temperature
°C
°F
30271
10E
MAX-Value Temperature
°C
°F
30273
110
MIN-Value Massflow
kg/h
kg/h
30275
112
MAX-Value Massflow
kg/h
kg/h
30277
114
MIN-Value Pressure
bar
psi
30279
116
MAX-Value Pressure
bar
psi
Write Registers (Function Code 0x06) / 16Bit integer Value
60261
104
Reset MIN/MAX-Value Standardized Flow
60262
105
Reset MIN/MAX-Value Standardized Volumetric Flow
60263
106
Reset MIN/MAX-Value Temperature
60264
107
Reset MIN/MAX-Value Massflow
60265
108
Reset MIN/MAX-Value Pressure
4.2.3. Data Transmission
Factory Setting
M-Bus
Factory Setting
Modbus
Adjustable Values
M-Bus
Modbus RTU
Baud Rate
2400
9600
600...9600
9600...57600
Data Bits
8
8
8
8
Parity
EVEN
EVEN
None, Odd, Even
None, Odd, Even
Stop Bits
1
1
1 or 2
1 or 2
Slave-Address
1
1
0...254
1...247
4.2.4. Addressing
The flowmeters are factory-set to address 1. The slave address can be set via switches on the PCB.
1 2 3 4 5 6 7 8
1 - ON
0 - OFF
1 2 3 4 5 6 7 8
1 - ON
0 - OFF
1 2 3 4 5 6 7 8
1 - ON
0 - OFF
1 2 3 4 5 6 7 8
1 - ON
0 - OFF
1 2 3 4 5 6 7 8
1 - ON
0 - OFF
1 2 3 4 5 6 7 8
1 - ON
0 - OFF
Factory Setting:
Slave-Address = 1
Slave-Address = 255
The address set using
the configurator software
is used.
Dip-Switch for address setting