Overview and definition of terms
1.7 "Override" mode
Fail-safe operation of the Mobile Panel 277F IWLAN
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Function Manual, 08/2008, 6AV6691-1FQ01-2AB0
1.7
"Override" mode
Introduction
The effective range functionality of the HMI device can be extended through the "override"
mode.
Applications
"Override" mode can be used in the following cases:
● Use of existing protective measures instead of the effective range functionality
If protective measures, such as protective fences are already available in your plant, then
you can integrate them in your safety concept with the "override" mode. Thus you achieve
a consistent concept for safe plant operation.
● If plant units, which do not allow themselves transponder coverage, (such as inside a
robot cell), will be operated with the enabling buttons.
In this case you must secure the plant area with additional protective measures, such as
a protective fence.
Requirements
Only use "override" mode in delimited plant units that are secured by additional protective
measures.
Entering and leaving the protected area must be monitored by the F-CPU.
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 activates "override" mode with this switch.
WARNING
Inadmissible activation of the "override" mode
The operator has to activate "override" mode through a conscious operator action, e.g. by
activating a switch. The "override" mode should not be automatically activated, e.g. when
the safety area is entered.
The application program in conjunction with F-FB must ensure that the "override" mode is
revoked when the area is left.
