3SK1121-1CB42

The Siemens SIRIUS 3SK1121-1CB42 is a relay output type safety relay that provides two sets of instantaneous and two sets of delayed (0.5~30 seconds) normally open safety contacts, screw terminal wiring, rated voltage 24VDC, and meets PL e, Cat.4 safety class. It is suitable for safety circuits that require long delay shutdown.

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The 3SK1121-1CB42 is a SIRIUS 3SK1 series relay-type safety relay with a built-in adjustable delay of 0.5 to 30 seconds. It uses screw terminal wiring and is suitable for safety circuits that require a longer buffer stop time.

Core Product Advantages and Features
Relay mechanical contact output
It provides a safety output using mechanical relay contacts and is suitable for general industrial safety interlocking circuits.
Adjustable delay from 0.5 to 30 seconds
The delay-enabled output has a long range, making it suitable for machine applications requiring a longer buffer downtime.
Screw terminal wiring
Standard screw terminal wiring method, compatible with existing wiring installation habits.
High security level certification
Compliant with ISO 13849-1 PL e, Cat.4 and IEC 62061/61508 SIL3 level
project Specification
Security level PL e (ISO 13849-1) / Category 4 / SIL 3 (IEC 62061, IEC 61508)
Rated voltage Us = 24 V DC
Delay range 0.5 ~ 30 seconds (adjustable)
Safe output 2 instantaneous normally open relays + 2 delayed normally open relays
Wiring method Screw terminals