GHM DeltaOHM BAROsense, Руководство по эксплуатации

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BAROsense
- 15 -
V1.2
6 MODBUS-RTU PROTOCOL
By default, the instrument has MODBUS address
1
and communication parameters
19200, 8E1. The address and the communication parameters can be changed by using
the appropriate serial commands of the proprietary protocol or, alternatively, directly
with MODBUS commands by changing the value of the Coils and Holding Registers de-
scribed later.
The MODBUS-RTU protocol, if set as the operating protocol (default), is active after 10
seconds from the instrument power on.
In order to change the instrument configuration using the MODBUS-RTU protocol, the
value 1 must be written first in the
Coil with address 1.
Below is the list of registers.
Input Registers:
Address Description Format
0 Pressure in the set unit of measurement ( see table on page
5 for the resolution
)
.
32-bit Integer
(2)
2 Pressure in the set unit of measurement ( see table on page
5 for the resolution
)
.
16-bit Integer
3 Power supply voltage in Volt [x10] 16-bit Integer
4 Internal temperature in the set unit of measurement [x10] 16-bit Integer
5 Error register:
0 = no error
1 = pressure error
2 = internal temperature error
3 = pressure and internal temperature error
16-bit Integer
Coils:
Address Description Format
0
Set 1 to restore the factory configuration. Bit zeroing is au-
tomatic.
Bit
1 Enable configuration change:
0=no (default), 1=yes.
The changes to
Coils and Holding Registers will be accept-
ed only if this register is set to 1.
Bit
2 Sets waiting time after transmission with MODBUS-RTU pro-
tocol:
0=immediate reception (default);
1=waiting 3.5 characters. Bit
3 Enable/disable the offset of the current analog output:
0=offset disabled (0…20 mA)
1=offset enabled (default, 4…20 mA) Bit
4 Sets the direct or reversed correspondence between current
analog output and pressure:
0=direct (default, Min. mA

Min. press., Max. mA

Max.
press.)
1=reversed (Min. mA

Max. press., Max. mA

Min. press.)
Bit