SIEMENS
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Siemens IC 10 · 2017
Safety Relays
SIRIUS 3SK Safety Relays
General data
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Benefits
General
•
Approved for all safety applications because of its compliance
with the highest safety requirements (SIL 3 and PL e)
•
Universally usable thanks to adjustable parameters
•
Usable worldwide thanks to globally valid certificates
•
Compact SIRIUS design
•
Device connectors with standard rail mounting for flexible
connectability and expandability
•
Removable terminals for greater plant availability
•
Yellow terminal covers clearly identify the device as a safety
component
•
Sensor cable up to 2 000 m long allows it to be used in
extensive plants
Relay outputs
•
Different voltages can be switched through the floating
contacts.
•
The power relay contacts allow currents of up to 5 A
at AC-15/DC-13 to be connected.
Semiconductor outputs
• Wear-free
•
Suitable for operation in frequently switching applications
•
Insensitive to vibrations and dirt
•
Good electrical endurance
Power outputs (3SK1213 output expansion)
•
Different voltages can be switched through the floating con-
tacts.
•
The power relay contacts allow currents of up to
10 A AC-15/6 A DC-13 to be switched.
•
High mechanical and electrical endurance
•
Protective separation between safe outputs and electronics
Expansion option by adding the 3RM1 motor starter
SIRIUS 3SK safety relays are ideal for combining with the
SIRIUS 3RM1 motor starters.
Combinations are made by means of
•
SIRIUS 3ZY12 device connectors (in combination with
3SK1 Advanced/3SK2) or
•
Conventional wiring (for all 3SK1 and 3SK2 basic units)
This makes collective shutdown very easy in assemblies. The
wiring, and ultimately the shutting down of the control supply
voltage for the expansion components in EMERGENCY-STOP
situations, is performed via the device connector. There is no fur-
ther need for complex looping of the connecting cables between
the safety relay and the motor starters.
The 3RM1 motor starter combines the benefits of semiconductor
technology and relay technology. This combination is also
known as hybrid technology.
The hybrid technology in the motor starter is characterized by
the following features:
•
The inrush current in the case of motorized loads is conducted
briefly via the semiconductors. Advantages include protection
of the relay contacts and a long service life due to low wear.
•
The uninterrupted current is conducted via relay contacts.
Advantages include lower heat losses compared with the
semiconductor.
•
Shutdown is implemented again via the semiconductor. The
contacts are only slightly exposed to arcs, and this results in a
longer service life.
•
Integrated overload protection
Note:
For SIRIUS 3RM1 motor starters,
see page 8/86
.
3ZY12 device connectors
Using 3ZY12 device connectors to combine devices reduces
the time required to configure and wire the components. At the
same time errors are avoided during wiring, and this consider-
ably reduces the testing required for the fully-assembled
application.
Configuration and stock keeping
Variable setting options by means of DIP switches or software, a
wide voltage range (3SK1111) and a special power supply unit
(3SK1 only) reduce the cost of keeping stocks and the consider-
ations involved in configuration where the evaluation units to be
selected are concerned.
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Application
3SK1 safety relays
SIRIUS 3SK1 safety relays are used mainly in autonomous safety
applications which are not connected to a safety-related bus
system. Their function here is to evaluate the sensors and the
safety-related shutdown of hazards. Also they check and
monitor the sensors, actuators and safety-related functions of
the safety relay.
3SK2 safety relays
SIRIUS 3SK2 safety relays are used primarily in autonomous,
more complex safety applications for which the functional scope
of the 3SK1 devices is no longer sufficient, such as in the imple-
mentation of independent shutdown functions. Their function
here is to evaluate the sensors and the safety-related shutdown
of hazards. Also they check and monitor the sensors, actuators
and safety-related functions of the safety relay.
© Siemens AG 2016