Siemens Simatic S7-400 Handbuch - Seite 13

Blättern Sie online oder laden Sie pdf Handbuch für Industrielle Ausrüstung Siemens Simatic S7-400 herunter. Siemens Simatic S7-400 35 Seiten. Block library motor starter sirius for simatic pcs 7 sirius motor starter pcs 7 library v7.1+sp2 / sirius motor starter pcs 7 library v8 migration 8.0+sp1
Auch für Siemens Simatic S7-400: Handbuch (18 seiten), Erste Schritte (36 seiten)

Siemens Simatic S7-400 Handbuch
Micro Automation Set 14
4

Principle of Operation

4.1

Acquisition and sending of process values with time stamp

Table 4-1
No.
1.
The central processing unit of S7-200
"Basis" acquires and stores process
values with time stamp to the second in a
reserved memory area of the S7-200
CPU.
2.
The generated data fields are written into
a data block of the S7-200 CPU at
intervals of one second. A data field
comprises two bytes for the measured
process value and six bytes for the time
stamp.
3.
The data block with the stored data fields
acts as send buffer. It buffers 20 data
fields before the send job is started. To
ensure consistency of the data at the
receiver, the actual send procedure is
divided into two steps:
Step1: Sending all 20 data fields +
consistency byte (status 0) to the
receiver
Step2: Sending the consistency byte
(status 1) after successful send
procedure of step 1. It is only now
that consistent availability of the data
at the receiver is ensured.
V2.0
Entry ID 21062588
Function
05/18/05
Principle of Operation
Comment
"
S7-200 "Basis
S7-200 "Basis
DB1
55
55
78 98
78
98
hour
minute
second
Data field
day
month
year
value
Step 1
Connection1:
192.168.2.XXX
Transfer data:
20 data records
Consistency byte (0)
Step 2
Connection1:
192.168.2.XXX
Transfer data:
Consistency byte (1)
"
13/35