SIEMENS
3/17
Siemens IC 10 · 2017
Power Contactors for Switching Motors
SIRIUS 3RT contactors, 3-pole up to 250 kW
3
Electromagnetic compatibility (EMC)
The 3RT contactors fulfill the requirements for environment
category A.
Note:
When the contactors are used in an environment with frequency
converters, the information in the manuals must be observed.
See "More information" on page 3/19
.
Short-circuit protection
For short-circuit protection of contactors without overload relays,
see "Technical specifications":
•
For 3RT2 contactors, see pages 3/24, 3/30, 3/34 and 3/39
•
For 3RT1 contactors, see page 3/44
Refer to the manuals for details of short-circuit protection of the
contactors with overload relays;
see "More information" on
page 3/19.
For fuseless assembly of motor feeders consisting of
3RV2 motor starter protector and 3RT2 contactor, selection
guides are available;
see "SIRIUS 3RA2 load feeders" from
page 8/4 onwards
.
Motor protection
3RT2 contactors
For protection against overload, 3RU2 thermal overload relays
(see page 7/84 onwards)
or 3RB3 electronic overload relays
(see page 7/97 onwards)
can be mounted on the 3RT2 contac-
tors.
3RT1 contactors
For protection against overload, 3RB2 electronic overload relays
(see page 7/109 onwards)
can be mounted on the 3RT1 contac-
tors.
Plant and application monitoring
For monitoring and measuring in the application,
3RR2 monitoring relays can be mounted on the 3RT2 contactors
(see page 10/62)
.
Ratings of three-phase motors
The quoted rating (in kW) refers to the output power on the motor
shaft (according to the nameplate).
The power rating specifications of the contactors in kW
(in accordance with IEC 60947-4-1, Table G) are guide values
for 4-pole standard motors at 50 Hz AC and specified voltage
(e. g. 400 V). The actual starting and rated data of the motor to
be switched must be considered when selecting the units.
Surge suppression
3RT contactors supplied without a coil circuit can be retrofitted
with RC elements, varistors, diodes or diode assemblies
(assembly of diode and Zener diode for short break times)
for damping opening surges in the coil.
See page 3/103
.
•
Size S00: the surge suppressors are plugged onto the front
of the contactors here. Space is provided for them next to a
snap-on auxiliary switch block.
•
Sizes S0 and S3: the surge suppressors can be plugged onto
the front of the devices. In the case of size S3 contactors,
surge suppressors can only be used as from product version
E03.
•
Sizes S6 to S12: Withdrawable coils with integrated coil switch
(varistor)
Note:
The OFF-delay of the NO contact and the ON-delay of the
NC contact are increased if the contactor coils are attenuated
against voltage peaks (for details,
see the relevant manual
"More information" on page 3/19
).
Contactors with voltage tap-off
Sizes S00 to S3
The S00 to S3 contactors with voltage tap-off are special
versions for mounting the SIRIUS function modules for connec-
tion to the control system through IO-Link or AS-Interface
(see page 3/79 onwards)
.
Without a function module, these contactors can be used like the
standard versions.
For more information on IO-Link and AS-Interface
see
"Industrial Communication" from page 2/1 onwards
.
Control supply voltage
Different versions of operating mechanisms are available
depending on the contactor size:
•
AC or DC operation for sizes S00 to S3
•
AC/DC operating mechanism for sizes S0 to S12 that can
operate on AC (50 to 60 Hz) or DC.
Operating mechanism types
Sizes S6 to S12
Two types of solenoid operation are available:
•
Conventional operating mechanisms
•
Solid-state operating mechanisms
- The operating mechanism for the contactors features solid-
state control of the contactor coil. Overvoltage damping of
the operating mechanism coil is already integrated in the
electronics. The operating mechanisms are powered via a
supply voltage with an operating range from 0.7 to 1.25 x
U
s
,
optionally also controlled depending on the chosen mode of
operation. Alternatively, control is via the separate 24 V DC
control signal input. Various rated voltage ranges for AC/DC
control are available.
- This version is additionally available with a 24 V DC PLC
relay output and a remaining lifetime indicator (RLT).
Solenoid coils
•
Sizes S0 to S3: coil replacement is possible.
•
As from size S6: For simple coil replacement, e. g. if the
application is replaced, the solenoid coil can be pulled out
upwards after the release mechanism has been actuated and
can be replaced by any other coil of the same size.
© Siemens AG 2016