Accessories and Spare Parts
For 3RT, 3RH Contactors and Contactor Relays
Accessories for 3RT, 3RH contactors and
contactor relays
■
Overview
Snap-on auxiliary contact blocks
The timing relays are suitable for both AC and DC operation.
The auxiliary switch blocks and the maximum number of blocks
that can be mounted are described in "Motor Contactors" and
"Contactor Relays".
Size S00
The version for size S00 contactors is fitted onto the front of the
contactor (with the supply voltage switched off) and then slid
into its latched position; at the same time, the timing relay is
connected by means of plug-in contacts to coil terminals A1 and
A2 of the contactor. Any contactor coil terminals which are not
required are sealed off by means of covers on the enclosure of
the time-delay block, to prevent them from being connected
inadvertently.
Solid-state time-delay auxiliary switch block
The timer module, which is available in "ON-delay" and "OFF-
delay" versions, allows time-delayed functions up to 100 s
(3 distinct delay ranges).
It contains a relay with one NO contact and one NC contact;
depending on the version, the relay is switched either after an
ON-delay or after an OFF-delay.
A varistor is integrated in the timer module in order to damp
opening surges in the contactor coil.
The timer module with "WYE-DELTA FUNCTION" is equipped
with one delayed and one instantaneous NO contact, with an
interval time of 50 ms between the two. The delay time of the
NO contact can be set between 1.5 s and 30 s.
The solid-state, time-delay block cannot be mounted on size S00
coupling relays.
Sizes S0 to S3
The time-delay block for size S0 to S3 contactors is plugged into
coil terminals A1 and A2 on top of each contactor; the timing
relay is connected both electrically and mechanically by means
of pins.
Wye-delta function:
A1/A2
Y 27/28
37/38
A varistor is integrated in the timer module in order to damp
opening surges in the contactor coil.
t
50 ms
The contactor on which the solid-state, time-delay auxiliary
switch block is mounted operates without a delay.
Note on configuration
a)
b)
L1
L1
Size S00
S1
K3
S1
K3
The solid-state, time-delay auxiliary switch block is fitted onto the
front of the contactor. The timer module is supplied with power
directly by plug-in contacts through the coil terminals of the
contactor, in parallel with A1/A2. The timing function is activated
by closing the contactor on which the auxiliary switch block is
mounted. The OFF-delay variant operates without an auxiliary
power supply; minimum on-time: 200 ms.
K3
A1 B1A2
A1 B1A2
1
2
1
2
A1 A2
A1
A2
N
N
$ Timing relay block
% Contactor
A varistor is integrated in the timer module in order to damp
opening surges in the contactor coil.
The activation of loads parallel to the start input is not
permissible when using AC control voltage (see (a) in the circuit
diagram).
The solid-state, time-delay auxiliary switch block cannot be
mounted on size S00 coupling relays.
The 3RT19 16-2D... / 3RT19 26-2D... OFF-delay timing relay
blocks have a zero potential start input B1. This means that if
there is a parallel load on terminal B1, activation can be
simulated with AC voltage. In this case, the additional load
(e.g. contactor K3) must be wired in accordance with (b).
Sizes S0 to S12
The solid-state, time-delay auxiliary switch block is fitted onto the
front of the contactor.
The timer module is supplied with power through two terminals
(A1/A2); the time delay of the auxiliary switch block can be
activated either by a parallel link to any contactor coil or by any
power source.
OFF-delay device for size S00 to S3 contactors
AC and DC operation
IEC 60947, EN 60947
The OFF-delay variant operates without an auxiliary power
supply; minimum on-time: 200 ms.
For screw and snap-on mounting onto 35 mm standard
mounting rail. The OFF-delay devices have screw terminals.
A single-pole auxiliary switch block can be snapped onto the
front of the contactor in addition to the timer module.
The OFF-delay device prevents a contactor from dropping out
unintentionally when there is a short-time voltage dip or voltage
failure. It supplies a downstream, DC-operated contactor with
the necessary power during a voltage dip, ensuring that the
contactor does not trip. The 3RT19 16 OFF-delay devices are
specifically designed for operation with the 3RT contactors and
3RH contactor relays of the SIRIUS series.
The timer module has no integrated components for damping
opening surges.
Solid-state time-delay block with semiconductor output
The timer module, which is available in "ON-delay" and "OFF-
delay with auxiliary voltage" versions, allows time-delayed
functions up to 100 s (3 distinct delay ranges). Contactors fitted
with a time-delay block close or open after a delay according to
the set time.
The OFF-delay device operates without external voltage on a
capacitive basis, and can be energized with either AC or DC
(24 V version only for DC operation). Voltage matching, which is
only necessary with AC operation, is performed using a rectifier
bridge.
The ON-delay variant of the timing relay is connected in series
with the contactor coil; terminal A1 of this coil must not be
connected.
A contactor opens after a delay when the capacitors of the
contactor coil, built into the OFF-delay device, are switched in
parallel. In the event of voltage failures, the capacitors are
discharged via the coil and thereby delay the opening of the
contactor.
With the OFF-delay variant of the timing relay, the contactor coil
is contacted directly through the relay; terminals A1 and A2 of
the contactor coil must not be connected.
Siemens LV 1 · 2006
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SIEMENS [ Siemens Semiconductor Group ]
