Siemens Sirius 3TK2826, Руководство пользователя

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Configuration / project engineering
9.3 Explanation of the device's functions
3TK2826 safety relay
Manual, 08/2007, GWA NEB 926 1579-02 DS 02
31
DIP
switch Parameter Function
8 Startup after
power failure
The parameters of the 3TK2826 device can be defined so that the enabling circuits switch
automatically to the active position after a power failure, i.e. without actuation of the start button
Y33.
Requirements:
• Y12, Y22 or the cascading input 1 are set to "monitored start".
• The switch-on condition at the sensor inputs and at the cascading input is satisfied.
•
The START button was actuated before the power failure and this was valid, i.e. the
enabling circuits were in the active position.
Safety shutdown mat operation
All safety shutdown mats and safety edges operating in a 4-wire configuration that work in
accordance with the principle of cross-circuit tripping can be connected to the 3TK2826
safety relay. Deactivation of the 3TK2826 is triggered by a cross-circuit of the two sensor
leads T1/Y12, T2/Y22.
The 3TK2826 evaluation unit can only be started if the T1/Y12 and T2/Y22 lead connection
has been established by contact blocks of the safety shutdown mat and there is no cross-
circuit of the signal leads due to tripping of the signaling device. This means that the device
remains in a safe state in the event of a discontinuity of the signal leads, or assumes the
safe state while switched through.
If the safety shutdown mat resistance is < 1000 Ω for the mat and the connecting leads, safe
evaluation is performed in accordance with DIN EN 1760-1 and DIN EN 1760-2.
Function of the cascading input (terminal 1)
1. Safe combination of safety relays
In this application, a higher-level safety relay switches off the 3TK2826 via the cascading
input.
Example:
an EMERGENCY STOP circuit is to deactivate the entire installation as a higher-level
circuit.
Several function groups (e.g., protective doors) that deactivate locally can be operated as
subordinate units.
WARNING
Application/safety relay safety category
When faults are ruled out (protected laying of the control lead), the application's safety
category corresponds to that of the higher-level safety relay.