Siemens sitrans LR 400 Instruction Manual And Users Manual page 101

The 3 function blocks (Level, Volume, Mass) return 5 bytes of data each:
Level byte 1
Volume
byte 6
Mass byte 11
The first 4 bytes are the floating point representation (IEEE) of the variable. The variables
are the outputs of the function block. The default setting for the variable level is meters.
The default setting for the variable volume is m
is kg. You can change the settings of the variables by changing the settings of the
function block. This is typically done using PDM.
The 5th byte is the status word and the list of possible values is given in the chart on
page 101.
The 5 bytes must be read consistently, in a contiguous chunk: they cannot be read byte by
byte, and cannot suffer an interrupt. If you are using an S7-300/400, you will need to use
SFC14 DPRD_DAT: Read Consistent Data of a Standard PD Slave.
If you select a Free Place module to fill one of the slots, this will affect the byte number.
Example 1:
Free
Place
Volume
Mass
Example 2:
byte1
Level
Free
Place
Mass
7ML19985FH04
Floating Point
byte 2 byte 3
byte 7 byte 8
byte 12 byte 13
Floating Point
— —
byte 1 byte 2 byte 3
byte 6 byte 7 byte 8
Floating Point
byte 2 byte 3
— —
byte 6 byte 7 byte 8
SITRANS LR 400 – INSTRUCTION MANUAL
byte 4
byte 9
byte 14
3
. The default setting for the variable mass
— —
byte 4
byte 9
byte 4
— —
byte 9
Status
byte 5
byte10 byte10
byte 15
Status
—
byte 5
byte 10
Status
byte 5
—
byte 10
Page 100