Siemens 3TK2845, Manual

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3TK2845 Multifunction Device Manual
5-10
GWA 4NEB 926 2087-22 DS 01
5.5 3TK2845-.EB40 "Enabling Button"
Brief description:
Monitoring an EMERGENCY-STOP control switch and a protective door with
monitored start-up and maintenance with enabling button according to Category 4,
EN 954-1.
Properties:
Stop category 0 according to EN 60204-1;
Two electronic enabling circuits;
Two floating enabling circuits;
One electronic signaling output;
U
s
24 V DC
Function:
Standard operation:
When the EMERGENCY-STOP control switch or the protective door is activa-
ted, outputs 14, 24 (M1) and 34, 44 (M2) switch off. The outputs are switched
back on again when the EMERGENCY-STOP control switch releases, the pro-
tective door is closed, the feedback circuit at Y64 is closed and the START but-
ton at Y34 on the 3TK281-.BB40 is activated.
Maintenance:
When the key-operated switch is operated, outputs 34, 44 (M2) switch off and
the position switches of the protective door are not evaluated. If the enabling
button is activated, outputs 34, 44 (M2) are switched on. When the key-operated
switch is operated once again with the protective door closed and the ON button
Y34 is activated, outputs 34, 44 (M2) switch on. If, however, the protective door
is not opened after the key-operated switch was activated, outputs 34, 44 (M2)
automatically switch on after the key-operated switch is activated once again.
Note:
Terminal Y32 can be used to choose between autostart (24 V) and monitored start
(0 V) for protective door input (Y41/Y42 and Y51/Y52).
Note:
Connecting several position switches in series for protective door monitoring is
not permissible for Category 4 according to EN 954-1 (fault detection).
Notice:
Sensor cables should be routed in a protected manner; only safety sensors with
positively-opening contacts may be used as sensors.
Notice:
If faults can be excluded (protected wiring of the control cable), the application's
safety category is the same as the safety category of the higher-level safety
relay.