SIEMENS
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Siemens IC 10 · 2017
Contactors for Special Applications
Contactors for Railway Applications
SIRIUS 3RT contactors with extended operating range, 3-pole
4
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Overview
Standards
IEC 60947-4-1, DIN EN 60947-4-1,
IEC 60077-2, DIN EN 60077-2
The contactors are finger-safe according to IEC 60529
(exception: S3 series resistor). The auxiliary conductor and
coil terminals are all spring-type terminals.
Ambient temperature
The permissible ambient temperature for operation of the
contactors (across the full coil operating range) is -40 to +70 °C.
Performance range
3RT contactors are available in all sizes from S00 to S12 up to
250 kW or 500 A (AC-3 at 400 V).
Operating range of contactor operating mechanisms
Sizes S00 to S3
The solenoid coils of the 3RT2 contactors have an extended coil
operating range from max. 0.7 to 1.25 x Us and are fitted as
standard with surge suppressors. The opening delay is conse-
quently 2 to 5 ms longer than for standard contactors.
Sizes S6 to S12
The operating mechanism for the 3RT10 contactors features
solid-state control of the contactor coil. Overvoltage damping
of the operating mechanism coil is already integrated in the elec-
tronics. The operating mechanisms are powered via a supply
voltage with an operating range of 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 to 110 V DC control
signal input.
Three rated voltage ranges are available as direct voltage (DC):
• 24 V DC
• 72 V DC
• 110 V DC
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Application
Besides standard approval in compliance with IEC 60974-4-1,
the contactors with an extended operating range are also
approved in compliance with IEC 60077-2, thus fulfilling the
requirement for use in railway applications.
Thus, their suitability for increased requirements such as an
•
extended temperature range in comparison with the regular
standard IEC 60497-4-1 or
•
extended operating range of the solenoid coils or also
•
increased resistance to mechanical oscillations and vibrations
is warranted. The design of the terminals in the spring-type
connection system also contributes toward vibration resis-
tance.
3RT20 contactors with conventional coil
Control and auxiliary circuits
These contactors have an extended operating range from
0.7 to 1.25 x
U
s
; on size S00 the coils are fitted with suppressor
diodes, on size S0 with varistors. An additional series resistor is
not required.
Note:
An additional auxiliary switch block cannot be mounted.
Side-by-side mounting
A clearance of 10 mm is required for side-by-side mounting at
ambient temperatures > 60 °C
70 °C.
3RT201 contactors with series resistor
Control and auxiliary circuits
The solenoid coils of these contactors have an extended coil
operating range from 0.7 to 1.25 x
U
s
and are fitted as standard
with a surge suppressor (suppressor diode or varistor as
preferred).
The DC solenoid systems of the contactors are modified
(to holding excitation) by means of a series resistor.
3RT201 to 3RT204 contactors with solid-state operating
mechanism, extended operating range
Control and auxiliary circuits
The solenoid coils of these contactors have an extended coil
operating range from 0.7 to 1.25 x
U
s
1)
and are fitted as stan-
dard with varistors to provide protection against overvoltage.
The contactors are energized via upstream control electronics
that ensure the coil operating range of 0.7 to 1.25 x
U
s
1)
at an
ambient temperature of 70 °C. They are supplied as complete
units with integrated coil electronics. A varistor is integrated for
damping opening surges in the coil.
The possibility of mounting auxiliary switches is the same as that
for equivalent standard contactors for switching motors in the
matching size
(see overview diagrams of the 3RT20 contactors
from page 3/7 onwards)
.
Side-by-side mounting
With these contactor versions in sizes S00 and S0, side-by-side
mounting is permitted at ambient temperatures up to 70 °C.
1)
Exception: 3RT204.-.X...-0LA2: 0.7 to 1.2 x
U
s
.
© Siemens AG 2016