BLH NOBEL G4-DT, Technical Manual

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Technical Manual
6-28
Data representation
Data sent to and from the instrument uses 16 bit holding registers (40XXX) and can
use different formats for flexibility.
Integer
Unsigned integer (1 modbus register)
Values stored in one modbus register as an unsigned integer
(16 bit number without decimals).
Scaled integer (2 modbus reg 1 modbus register = 3 modbus registers)
Values stored in a special 3 register format. The first two registers are used as
a 32 bit long integer value (with sign) and the third register is holding the number of
decimals in the value.
Example: 12345678 (32 bit number) in the two first registers and 3 in the third register
give the value: 12345.678.
Register Hex Decimal Description
1 00BC 188 The 16 most significant bits in the value.
2 614E 24910 The 16 least significant bits in the value.
3 0003 3 The number of decimals.
Calculations in decimal numbers:
First multiply the most significant register with 2
16
(65536) and add
the least significant register to the value.
188 * 2
16
+ 24910 = 12345678
Now divide the number to get the right number of decimals. The decimal register was
set to 3 in this example, which gives the value 10
3
= 1000 to divide with.
12345678 / 1000 = 12345.678
Note: If you want to read weight or flow rate values and your PLC system can’t handle
32 bit values, the second register can be used as a 16 bit register with the number of
decimals that is indicated in the third register. This will limit the value range to -32768
to +32767. Flags in Status register for corresponding scale indicates when the weights
are bigger than a 16 bit integer. These flags must be checked to be sure that the
weight or flow value fits in just one register.