Appendix; Assembly; General Rules And Regulations For S7-300 Operation; Starting The System After Specific Events - Siemens SIMATIC S7-300 Hardware And Installation Manual

Appendix

12.1

Assembly

12.1.1

General rules and regulations for S7-300 operation

Introduction
In view of the many and versatile S7-300 applications, this chapter can only
describe the basic rules on its electrical configuration. You must observe at least
these basic rules if you want your S7-300 to operate free of trouble.
EMERGENCY-OFF devices
EMERGENCY-OFF devices to IEC 204 (corresponds to VDE 113) must remain
effective in all operating modes of the plant or system.
start-up of the system after specific events
The following table shows you what you have to observe when starting up a plant
again following specific events.
Table 12-1
If there is...
Restart following a voltage dip or power
failure,
start-up after releasing the EMERGENCY
OFF device:
S7-300 Programmable Controller Hardware and Installation
A5E00105492-02

Starting the system after specific events

What must not happen ...
No dangerous operating states may occur. If
necessary, force EMERGENCY-OFF.
An uncontrolled or undefined start-up must
be avoided.
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12-1