SIEMENS
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Siemens IC 10 · 2017
Power Contactors for Switching Motors
Accessories and Spare Parts for SIRIUS 3RT Contactors and SIRIUS 3RH2 Contactor Relays
Accessories
3
SIRIUS 3RA27 function modules for IO-Link or AS-Interface
for mounting on 3RT2 contactors
See pages 3/86 and 3/106
The SIRIUS 3RA27 function modules enable the assembly of
starters and contactor assemblies for direct-on-line, reversing
and star-delta (wye-delta) starting without any additional, com-
plicated wiring of the individual components. They include the
key control functions required for the particular feeder, e.g.
timing and interlocking, and can be connected to the control
system via either IO-Link or AS-Interface.
The electrical and mechanical connection to the contactor is
established by snapping on and locking. An additive protection
circuit for the individual contactors can be dispensed with com-
pletely because a varistor is integrated in the modules. Feed-
back from the contactor contacts is performed with Hall sensors
which provide reliable feedback concerning the switching state
even under extremely dusty conditions.
The starters are connected to the higher-level control system
through IO-Link, with the possibility of connecting up to four
starters as a group to one port of the IO-Link master,
or optionally via AS-Interface, Specification V2.1 or higher, in
A/B technology. As a result, up to 62 starters can be connected
to one master and the address is entered in the normal manner
with an addressing unit.
Through this type of connection to the control system, a maxi-
mum of wiring is saved. In the case of AS-Interface, the wiring
amounts to the control supply voltage and the two individual
wires for AS-Interface.
The following essential signals are thus transmitted:
•
Availability of the feeder in response to an indirect inquiry from
the motor starter protector/circuit breaker
•
Starter control
•
Feedback concerning the switching state of the starter
Signal transmission through IO-Link
Signal transmission through AS-Interface
NSB0_02084a
Control
Availability
Feedback through
switching state
PLC
IO-Link
PLC
NSB0_02085a
Control
Availability
Feedback through
switching state
PLC
AS-Interface
PLC
© Siemens AG 2016