Data type definitions
51
SIPROTEC PROFIBUS-DP - Communication profile
C53000-L1840-B001-03
3.6 Metered measurand (unsigned long)
Number of
byte-values
4
Range of values 0 to +4294967295
Figure 3-6 Data type: Metered measurand (unsigned long)
Status bit (S) The status bit is set for invalid metered measurands in case of:
• corruption of the metered measurand after device reset/device start-up
(the status bit is deleted after two update cycles of the metered measurand after
device reset/device start-up),
• the external error bit of a pulse counter (metered measurand with a pulsed binary
input as source) is set.
Byte 3 (MSB) Byte 2 Byte 1 Byte 0 (LSB)
S
Metered measurand
Message head ... ... Message end
Note:
• The overflow of the metered measurands is 7FFFFFFF
hex
+ 1 and the counter then
starts at 0 again.
• The transmission of a status bit for metered measurands can be disabled in appli-
cation cases the metered measurand’s status bit is not required or if it could lead to
miscalculations in the PROFIBUS-DP master (ref. to chap. 2.1, Parameter
GlobalSection.DP_CountersWithStatus).
The status bit is always 0 if it is disabled.
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