Bender ISOMETER isoCHA425 Manual page 24

Modbus register assignment of the ISOMETER®
8.1 Device-specific data type of the ISOMETER®
8.1.1 Device name
The data format of the device name is specified below.
Word
0x01 0x02 0x03
0x00
10 Words in total
Each Word contains two ASCII characters
8.1.2 Measuring values
Each measuring value is available as a channel and consists of 8 bytes (4 registers). The
first measuring value register address is 1000. The structure of a channel is always identi-
cal. Content and number depend on the device. The structure of a channel is shown with
the example of channel 1:
1000 1001
HiByte LoByte HiByte LoByte HiByte
Alarm type and
Floating point value (Float) test type
(AT&T)
8.1.2.1 Float = Floating point value of the channels
0x00
HiByte LoByte
S E E E E E E E E M M M M M M M M M M M M M M M M M M M M M
Presentation of the bit order for processing analogue measuring values according to
IEEE 754
S = Sign; E = Exponent; M = Mantissa
24
------------------- 0x08 0x09
1002 1003
LoByte HiByte LoByte
Range and Channel
unit (R&U) description
0x01
HiByte LoByte
M M
Modbus register assignment of the ISOMETER®
8.1.2.2 AT&T = Alarm type and test type (internal/external)
Bit 7 6 5 4 3
X X X X X
X X X X X
0 0 X X X
X X X X X
X X X X X
X X X X X
X X X X X
X X X X X
X X X X X
0 0 X X X
0 1 X X X
1 0 X X X
The alarm type is coded by bits 0 to 2. Bits 3, 4 and 5 are reserved and always have the
value 0. Bit 6 or 7 is usually set when an internal or external test has been completed.
Other values are reserved. The complete byte is calculated from the sum of the alarm type
and the test type.
2 1 0 Meaning
0 0 0 No alarm
0 0 1 Prewarning
0 1 0 Device error
0 1 1 Reserved
1 0 0 Warning
1 0 1 Alarm
1 1 0 Reserved
... ... ... Reserved
1 1 1 Reserved
X X X No test
X X X Internal test
X X X External test
isoCHA425_D00352_01_M_XXEN/10.2019