Operating Instructions
L4000 system
Recommendation
Note
8010009/YTA2/2016-05-02
Subject to change without notice
Product description
The reset button prevents the accidental and inadvertent operation of
the external restart button. The user must first acknowledge the
dangerous state with the reset button.
Mounting and electrical connection of the reset button are described
on page 88.
3.2.2 External device monitoring (EDM)
The external device monitoring (EDM) checks if the contactors
actually de-energise when the protective device responds. If you
activate external device monitoring, then the L4000 system checks
the contactors after each interruption to the light path and prior to
machine restart. The EDM can so identify if one of the contacts has
fused, for instance. In this case
• the error message 7 appears on the 7-segment display
• the LED on the safety evaluation device UE401 illuminates red
• with internal restart interlock activated, the safety evaluation
device UE401 indicates "Reset required" by means of the
illumination of the LED Ν yellow.
If the system is unable to change to a safe operational state (e.g.
after contactor failure), the system locks and shuts down completely
("Lock-out"). The 7-segment display will then show the error message
∋.
The electrical connection for the external device monitoring is des-
cribed in chapter 5.2.
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Chapter 3
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