System Startup
S5-115F Manual
The CPU controls are arranged in a panel on the front of the CPU and are shown in Figure 4-3
below.
CPU 942F
RUN / STOP mode selector
Switch for Overall Reset (OR)
For safety reasons, there is no ”retentive /
nonretentive” setting.
Mode LEDs
RN
ST
RN
ST
OR
Figure 4-3. CPU Control Panel
4.1.2
Operating Modes
Use the mode selector to set the ”STOP” (ST) or ”RUN” (RN) mode. The CPU executes the initiali-
zation program automatically on power up and the ”RESTART from STOP” program when the
RUN mode is selected.
”RESTART from POWER ON” program and ”RESTART from STOP” program
•
Restart block OB 22 (RESTART from POWER ON) or OB
21 (RESTART from STOP) is processed.
•
All input and output modules are disabled. Outputs have signal state ”0”.
•
All inputs and outputs in the process image have signal state ”0”.
•
Scan time monitoring is inactive.
•
No restart test is run in test mode ( 4.1.3).
•
The restart test (approx. 2 min.) is run in safety mode ( 4.1.3) .
!
Important
When the CPU goes from ”STOP” to ”RUN”, the process images and the nonretentive
flags, timers and counters are set to zero.
4-4
EWA 4NEB 811 6148-02