Siemens SIRIUS 3SK1, Manual

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3SK1 devices
5.3 3SK1 output expansions
3SK1 safety relays
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Manual, 04/2013, A5E02526190021A/RS-AA/01
5.3 3SK1 output expansions
5.3.1 Applications
The 3SK1 output expansions are used to expand the enabling circuits. The maximum
achievable Performance Level PL / Cat. in accordance with ISO 13849-1, SILCL in
accordance with IEC 62061, SIL in accordance with IEC 61508 corresponds to the
Performance Level PL and SIL of the basic unit when the external wiring (connection
between basic unit and output expansion) is configured as fail-safe (e.g. basic unit and
output expansion are connected using 3ZY12device connector ).
The output expansions can be activated via the supply voltage (A1/A2) or using 3ZYdevice
connectors
1)
.
1)
For 24 V DC variant only
Note
Use of the output expansions on device connectors 3ZY
You can switch between instantaneous or delayed control of the basic unit using the slide
switch of the output expansion (see also the chapter "System configuration rules
(Page 100)").
Note
Using the output expansions with conventional wiring
The slide switch has no function here.
If you require outputs of Stop category 1 with the output expansion, terminals A1/A2 of the
output expansion must be connected to outputs 38 or 48, and on the 3SK1 basic units they
must be connected with relay outputs or Q1t/Q2t.
5.3.2 Function description
The operating state of the 3SK1 output expansions is displayed on the DEVICE LED.
The output expansions 3SK1211(4RO) have four safety-related enabling circuits as NO
circuits, and the output expansions 3SK1213 (3RO) have three. They each have one
positively-driven NC circuit. The output expansions can be activated via any enabling circuit /
output of the basic unit via (A1). The NC circuit 51/52 of 3SK1211 (4RO) or 41/42 of
3SK1213 (3RO) is used for monitoring the output expansions.
In the 24 V DC variants, the expansion units can be activated and evaluated via the 3ZY
device connectors.