Siemens SIMATIC S5 Manual page 325

IP 266
"Automatic" positioning sequence as per example 2
State 1: Job terminated and flag 3.0=0; no job initiated, drive is at a
standstill:
Motor must be started by setting F 3.0 to "1".
State 2: Job terminated and flag 3.0=1:
The TOGGLE FB is entered and a new mode preset.
State 3: Job terminated and flag 3.0=0, but no job order has been initiated:
Loops are run through but no activities performed.
State 4: Job in progress and flag 3.0=0:
Flag 3.0 is set to "1", thus making it possible to issue a new job
request. The only condition that has not yet been met to enable a
new job to be started is the "Job terminated" bit from the IP 266's
input message.
The next possible state is the same as state 2. Alternate positioning
in a positive and negative direction must be programmed in the
TOGGLE FB.
Summary:
The example enables generation of a new job request only when the "Job
terminated" bit has been read. It is thus unnecessary to terminate an old job with
STOP before starting a new one.
• Condition for issuing a new request:
Job terminated and F 3.0=1
• Condition for setting flag bit F 3.0 to "1":
Job in progress
Once the automatic sequence has been started, positioning continues until the
FB 11 call has been deactivated in OB 1.
EWA 4NEB 812 6057-02
STEP 5 Programming
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