turck BL67 - Page 475

D300529 0115 - BL67 I/O modules
15-15
Analog value representation (analog input modules)
Voltage values from 0 to 10 V DC
Before using the equation below, the hexadecimal or binary value has to be converted into a decimal
value.
The hexadecimal/binary value can easily be converted into a decimal value, because all numbers
belong to the positive range of the two’s complement
(→ page 15-9).
The value range:
(0 VDC to 10 VDC
is displayed as follows:
0000
hex
to 7FFF
hex
(decimal: 0 to 32767)
The voltage value can now be calculated by means of the following equation:
voltage value = 3,05185 mV × 10
-4
× decimal value
Voltage values from -10 to 10 V DC
Before using the equation below, the hexadecimal or binary value has to be converted into a decimal
value.
The hexadecimal/binary values for the negative value range cannot easily be converted into decimal
values, because the values are coded as two’s complement (→
page 15-9).
All numerical values from 0000
hex
to 7FFF
hex
represent positive values when coded as two’s comple-
ment. Values in this range can easily be converted into decimal values. This is also relevant for binary
numbers in which the most significant bit (bit 16) is "0".
All numerical values from 8000
hex
to FFFF
hex
represent negative values when coded as two’s comple-
ment. This is also relevant for binary numbers in which the most significant bit (bit 16) is "1". Please see
→
Example of the conversion of negative numerical value, page 15-10.
The value range:
-10 V to -3,052 10
-4
V
is displayed as follows:
8000
hex
to FFFF
hex
(decimal:-32768 to -1)
The value range:
0 V to 10 V
is displayed as follows:
0000
hex
to 7FFF
hex
(decimal: 0 to 32767)
voltage value = 3,05185 mV × 10
-4
× decimal value