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4 Modbus protocol description
4.9.2 Error messages for invalid values
For measured values in the float format, the error number appears directly in
the value, i.e. the error number is entered instead of the measured value.
Example Data request:
Response:
The measured value 0x7DB48E52 (=3.0 x 10
37
) supplied by analog input 2
(Modbus address 0x1259) indicates that the input value is invalid.
Error code
for float values
Error
1.0 x 10
37
Underrange
2.0 x 10
37
Overrange
3.0 x 10
37
No valid input value
4.0 x 10
37
Division by zero
5.0 x 10
37
Math error
6.0 x 10
37
Invalid terminal temperature of thermocouple
7.0 x 10
37
Invalid float value
8.0 x 10
37
Integrator or statistics destroyed
01 03 1259 0002 1160
01 03 04 8E52 7DB4 51ED