Operating Instructions
L 4000 system
Note
8010009/TI69/2009-11-26
Product description
Mounting and electrical connection of the reset button are described
on page 307.
3.2.2 External device monitoring (EDM)
The external device monitoring (EDM) checks if the contactors actu-
ally de-energise when the protective device responds. If you activate
external device monitoring, then the L 4000 system checks the con-
tactors 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
the LED on the safety evaluation device UE 401 illuminates red
with internal restart interlock activated, the safety evaluation device
UE 401 indicates "Reset required" by means of the illumination of
the LED
yellow.
If the system is unable to change to a safe operational state (e.g. af-
ter 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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appears on the 7-segment display
Chapter 3
289