Chapter 3
Fig. 1:Sketch illustration of
the L 4000 system
Note
WARNING
Recommendation
288
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Product description
3.2.1 Restart interlock
Do not confuse the restart interlock with the start interlock on the
machine. The start interlock prevents the machine starting after
switching on. The restart interlock prevents the machine starting again
after an error or an interruption in the light path.
The restart interlock can be implemented in two different ways:
With the internal restart interlock of the L 4000 system. During this
process the L 4000 system controls the restart.
With the internal restart interlock of the machine (external). During
this process the L 4000 system has no control over the restart.
Always operate the application with restart interlock!
Ensure that a restart interlock is always activated. The L 4000 system
is unable to verify if the external restart interlock on the machine is
operable. If you deactivate both the internal and the external restart
interlock, the operator of the machine will be at acute risk of injury.
Reset
If you want to activate the internal restart interlock on the L 4000 sys-
tem and an external restart interlock on the machine, then each re-
start interlock has its own button.
When the reset button for the internal restart interlock is operated
The L 4000 system activates the switching outputs
The LED on the safety evaluation device UE 401 illuminates green
Only the external restart interlock prevents the machine from restart-
ing. After pressing the reset button for the L 4000 system, the opera-
tor must also press the restart button for the machine. If the reset
button and the restart button are not pressed in the specified se-
quence, the dangerous state remains halted.
The reset button prevents the accidental and inadvertent operation of
the external restart button. The user must first acknowledge the dan-
gerous state with the reset button.
Operating Instructions
UE 401
L 400/L 4000
8010009/TI69/2009-11-26
L 4000 system