SIEMENS
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Siemens IC 10 · 2017
Switching Devices – Contactors and Contactor Assemblies
Contactor Relays and Relays
Introduction
5
Connection methods
The contactor relays and the relays are available with screw
terminals (box terminals) or with spring-type terminals.
Devices of the 3TH2 series are also available with screw
terminals, flat connectors and solder pin connectors.
The 3RQ3 coupling relays are supplied with screw terminals and
spring-type (push-in) terminals. The plug-in bases for
LZS/LZX coupling relays are also available with plug-in (push-in)
terminals.
3RQ coupling relays: Spring-type terminals (push-in) with
TOP-wiring
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 finely-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 terminals.
With the TOP wiring method, the wire inlet and terminals can be
reached from the front. This helps to speed up the wiring
process and eliminate wiring errors.
SUVA-certified safety contactors
We offer special safety contactors for use in safety-related appli-
cations. They have NC contacts with mirror contact function and
they have SUVA certification. This means they have permanently
fitted auxiliary switch blocks and cannot be operated manually.
They thus comply with all requirements for use in safety applica-
tions.
Screw terminals
Spring-type terminals,
spring-type terminals (push-in)
Flat connectors
Solder pin connections
Plug-in terminals (push-in)
The terminals are indicated in the corresponding
tables by the symbols shown on orange backgrounds.
© Siemens AG 2016