turck BL20 Series - 17.1.2 Equations for 12-bit representation

501
2020/09
17.1.2 Equations for 12-bit representation
The 12-bit-representation is ”left-justified”. The value is transmitted with 16 bit. The last 4 digits of
the binary number or respectively the last digit position of the hexadecimal value are used as diag-
nostic bits!
Before using the equation below, the hexadecimal or binary value has to be converted into a deci-
mal value. The value is contained in the 3 more significant digit positions of the hexadecimal num-
ber or in the 12 more significant bits of the binary number.
In the 12-bit-representation only the 3 more significant digit positions of the hexadecimal number
or the 12 more significant bits of the binary number are used for the calculation of the decimal value.
Current values from 0…20 mA
The value range:
0…20 mA
is displayed as follows:
000
hex
…7FFF
hex (decimal:
0…4095)
The hexadecimal/binary value can easily be changed into a decimal value.
The current value can now be calculated by means of the following equation:
Current values from 4 bis 20 20 mA
The value range:
4…20 mA
is displayed as follows:
000
hex
…7FFF
hex
(decimal: 0…4095)
The hexadecimal/binary value can easily be changed into a decimal value.
The current value can now be calculated by means of the following equation:
voltage value = 4.88 × 10
-3
mA × decimal value
current value = 3.91 x 10
-3
× decimal value