For The "Override" Mode: Planning The Protective Devices - Siemens Second Wind Function Manual

3.5

For the "Override" mode: Planning the protective devices

Introduction
Use "override" mode to extend the effective range concept.
Requirements
Only use "override" mode in delimited plant areas that are secured by additional protective
measures.
The operator must be able to fully see the area for which "override" mode applies. The
danger location must be visible from every point of the override area.
When using the "override" mode you must install a switch within an effective range that is
independent of the HMI device.
The operator logs his HMI device on at the effective range and activates "override" mode
with this switch.
Suitable additional protective measures
When using "override mode you must provide additional protective measures in your plant
which prevent unauthorized use or incorrect operation of the HMI device. The additional
protective measures must have a safety category that is commensurate with the plant
requirements.
For example the following measures are suitable:
● Grate with protective door
● Light barrier
● Foot grating / safety shutdown mat
● Additional plant-typical safety measures
If you use a grating with a protective door, you have to protect against access to the override
area using a further protective measure, e.g a light barrier or a foot grating. This enables you
to leave the protective door open as an escape route during operation of the plant in
"override" mode.
Safety program
The "override" mode may only be activated as long as the safety measure is active.
If the operator leaves the protected area, the "override" mode must be automatically ended.
Example of an application
A detailed example of an application can be found in the section Application example: Safety
Functions (Page 113) .
Fail-safe operation of the Mobile Panel 277F IWLAN
Function Manual, 08/2008, 6AV6691-1FQ01-2AB0
3.5 For the "Override" mode: Planning the protective devices
Application Planning
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