Siemens SIMATIC S5-115U, User Manual

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S5-115U Manual Active and Passive Faults in Automation Equipment
D Active and Passive Faults in Automation
Equipment / Guidelines for Handling
Electrostatic Sensitive Devices
Active and Passive Faults in Automation Equipment
• Depending on the particular task for which the electronic automation equipment is used, both
active as well as passive faults can result in a dangerous situation. For example, in drive
control, an active fault is generally dangerous because it can result in an unauthorized startup
of the drive. On the other hand, a passive fault in a signalling function can result in a
dangerous operating state not being reported to the operator.
• The differentiation of the possible faults and their classification into dangerous and non-
dangerous faults, depending on the particular task, is important for all safety considerations
in respect to the product supplied.
Warning
In all cases where a fault in automation equipment can result in severe personal injury
or substantial property damage, i.e., where a dangerous fault can occur, additional
external measures must be taken or equipment provided to ensure or force safe
operating conditions even in the event of a fault (e.g., by means of independent limit
monitors, mechanical interlocks, etc.).
Procedures for Maintenance and Repair
If you are carrying out measurement or testing work on a PLC, you must adhere to the rules and
regulations contained in the "VGB 4.0 Accident Prevention Regulations" of the German employers
liability assurance association ("Berufsgenossenschaften"). Pay particular attention to § 8,
"Permissible exceptions when working on live parts".
Do not attempt to repair an item of automation equipment yourself. Such repairs may only be
carried out by Siemens service personnel or repair shops Siemens has authorized to carry out such
repairs.
The information in this manual is checked regularly for updating and correctness and may be modified without prior
notice. The information contained in this manual is protected by copyright. Photocopying and translation into other
languages is not permitted without express permission from Siemens.
EWA 4NEB 811 6130-02b
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