SIRIUS 3SK1 Safety Relays Siemens

Область применения

SIRIUS 3SK1 safety relays are used mainly in autonomous safety applications which are not connected to a safety-oriented bus system. Their function here is to evaluate the sensors and the safety-oriented shutdown of hazards. Also they check and monitor the sensors, actuators and safety-oriented functions of the safety relay.

Обзор

SIRIUS 3SK1 safety relays

SIRIUS 3SK1 safety relays are the key elements of a consistent, cost-effective safety chain. Whether you need EMERGENCY-STOP disconnection, protective door monitoring, light arrays, laser scanners or the protection of presses or punches – with SIRIUS safety relays 22.5 mm wide every safety application can be implemented to optimum effect in terms of engineering and price.

The following safety-oriented functions are available:

• Monitoring the safety functions of sensors
• Monitoring the sensor leads
• Monitoring correct functioning of safety relays
• Monitoring the actuators in the shutdown circuit
• Safety-oriented disconnection when dangers arise

SIRIUS 3SK1 safety relays satisfy the most stringent requirements of IEC 61508/IEC 62061 (SIL 3) and EN ISO 13849-1 (PL e).

SIRIUS 3SK1 safety relays stand out due to their flexibility for both parameterization and system designs with several evaluation units. Optimized solutions when selecting components are facilitated by a clearly structured component range:

• Standard basic units
• Advanced basic units
• Output expansions
• Input expansions
• Accessories

The 3SK1 Standard basic units are characterized by the following features:

• Compact design
• Simple operation
• Relay and semiconductor outputs
• Economical solution

However, the 3SK1 Advanced basic units also offer the following:

• Universal application opportunities thanks to multifunctionality
• Time-delayed outputs
• Expansion of inputs and outputs

In the case of Advanced basic units, the 3ZY1 device connector allows safety functions involving several sensors and actuators to be constructed very quickly.

The 3SK1 Standard and Advanced series are a high-quality replacement for the 3TK28 safety relays. In their narrower design, and equipped with greater functionality, they can replace every 3TK28 device. The only exceptions are devices with special functions, such as 3TK28 26, 3TK28 45 and the 3TK28 10 devices. See below for an order number reassignment table 3TK28 to 3SK1.

Functional overview of the 3SK1 series

✓ Available

-- Not available

1) Possible using 3SK1 230 power supply via device connector.

3SK1 12 and 3SK1 112 safety relays with DIP switch

The 3 SK1 12 and 3SK1 112 safety relays are configurable safety relays. They are used as evaluation units for typical safety chains (detect, evaluate, deactivate). A number of functions can be set using the DIP switches on the front. This makes the 3SK1 12 and 3SK1 112 universally usable.

OFF	Circuit diagram	DIP switch no.	ON
Autostart sensor input		1	Monitored start sensor input
without crossover monitoring		2	With crossover monitoring
2 x single-channel sensor connection		3	1 x 2-channel sensor connection
with start test		4	without start test

Number of safe outputs

✓ available

-- not available

Can be expanded by adding the 3RM1 motor starter

With previous safety relay and motor starter designs an enormous amount of wiring was required to monitor the motor starters in safety applications.

Traditional system design

With the integration of the SIRIUS 3RM1 motor starter into the SIRIUS 3SK1 safety relay system family, this wiring has been minimized for the first time.

Motors up to 3 kW can easily be integrated into the safety relay system using SIRIUS 3ZY1 device connectors, without having to run a cable between the evaluation unit and the motor starter.

System design using 3SK1 and 3RM1

Order number reassignment table

The table below lists the existing 3TK28 order numbers with the corresponding 3SK1 order numbers.

Order No. scheme

Note:

The Order No. scheme is presented here merely for information purposes and for better understanding of the logic behind the order numbers.

Особенности

General

• Suitable for all safety applications because of its compliance with the highest safety requirements (SIL 3 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 large-scale plants.

Relay outputs

• Different voltages can be switched through the floating contacts
• Higher currents can be switched with relay contacts

Solid-state outputs

• Wear-free
• Suitable for operation in fast switching applications
• Insensitive to vibrations and dirt
• Good electrical endurance

Power outputs (3SK1 213 output expansion)

• Different voltages can be switched through the floating contacts
• The power relay contacts allow currents of up to 10 A AC-15/DC-13 to be connected.
• Long mechanical and electrical endurance
• Protective separation between enabling circuits and between enabling circuits and electronics

Can be expanded by adding the 3RM1 motor starter

SIRIUS 3SK1 safety relays are ideal for combining with the 3RM1 motor starters.

Combinations are made by means of

• SIRIUS device connectors (3SK1 Advanced) or
• conventional wiring (3SK1 Standard and Advanced).

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 further need for complex looping of the connecting cables between the safety relay to 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 the SIRIUS 3RM1 motor starter, see "Load Feeders and Motor Starters for Use in Switchgear Cabinets" → "SIRIUS 3RM1 Motor Starter".

3ZY1 device connector

Using 3ZY1 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 considerably reduces the testing required for the fully-assembled application.

Microprocessor systems

• Flexible use thanks to many different integrated functions
• Easy parameterization using DIP switches on the front
• High functional reliability based on extensive monitoring functions
• Operated by the machine control
• Also connection of non-contact sensors (light arrays, light barriers etc.)

Configuration and stock keeping

Variable setting options by means of DIP switches, a wide voltage range and a special power supply unit reduce the cost of keeping stocks and the considerations involved in configuration where the evaluation units to be selected are concerned.

Spring-type terminal with push-in functionality

Push-in connections are a form of spring-type terminals allowing fast wiring without tools for rigid conductors or conductors equipped with end sleeves.

As with other spring-type terminals, a screwdriver (with 3.0 x 0.5 mm blade) is required to disconnect the conductor. The same tool can also be used to wire fine-stranded or stranded conductors with no end finishing.

The advantages of the push-in terminals are found, as with all spring-type terminals, in speed of assembly and disassembly and vibration-proof connection. There is no need for the checking and tightening required with screw-type connections.

Дальнейшая информация

For the manual "3SK1 Safety Relays" see

https://support.industry.siemens.com/cs/ww/en/view/67585885.

For “3SK2 safety relays” manual, see

https://support.industry.siemens.com/cs/ww/en/ps/16386.