Siemens 3TC44 Operating Instructions Manual Download Page 2

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3ZX1012-0TC44-1AA1

DC contactors

3TC44, 3TC48, 3TC52, 3TC56

EN 60947-4-1, IEC 60947-4-1

Operating Instructions

English

EN 1088(5.7)

Read and understand these instructions before installing, operating
or maintaining the equipment.

Mount the device on a level surface. Install the contactor in a housing if there is a
risk of fouling, dust accumulation or aggressive atmosphere.
Permissible mounting position: coil connection on top, see

Fig. I

Snap-on mounting

: 3TC44

Snap-on mounting onto 35 mm standard mounting rail acc. to EN 50022.

Screw mounting

: 3TC44, 3TC48, 3TC52, 3TC56

Screw mounting on a vertical, level surface.
3TC44: 2 M4 screws; 3TC48: 2 M5 screws; 3TC52: 4 M6 screws; 3TC56: 4 M8
screws. Always use washers and spring washers!
For

dimension drawings

(dimensions in mm) see

Fig. I

3TC44..-0A, 3TC48..-0A, 3TC52..-0A, 3TC56..-0A

3TC44..-0B, 3TC48..-0B, 3TC52..-0B, 3TC56..-0B

1) = DC operation only 3TC56
t = Minimum clearance

of insulated components

of grounded components

Drilling templates for fastening holes
3TC44, Order No.: X 203 / 1078; 3TC48, Order No.: X 203 / 1080

For conductor cross-sections

see

Fig. II

Main conductor:

Screw connection for straight conductor ends

3TC44: a) Solid

b) Finely stranded with end sleeve

Circular conductor with cable lug

Busbars

Terminal screws (separately packed with 3TC48, 3TC52, 3TC56) / Nm

Auxiliary conductors:

Solid

Finely stranded with end sleeve

Terminal screw / Nm

To connect the main conductor

of 3TC48, 3TC52, 3TC56:

The spring washer (a) is required to lock the screw. The toothed lock washer (b)
merely simplifies the work of fitters and prevents the screw from inadvertently
turning. There is thus no need to steady the screw head. The toothed lock washer
does not affect the locking action of the spring washer. Tighten all terminal screws
(including any that are not used!).

Internal circuit diagrams

(terminal markings acc. to DIN EN 50012)

With auxiliary switches (2 NO + 2 NC)

Circuit diagrams

(typical)

Momentary-contact control

Maintained-contact control

S = Pushbutton

K = Contactor

For maintenance

see

Fig. III

Remove any dust deposits by suction. Contacts with a rough surface and dark
discoloring still function reliably and should be neither reworked nor greased!
Contacts should be replaced if their surfaces (K) have eroded to the extent that the
carrier material (T) is partially visible, see

and

. Contacts are allowed to be

individually replaced if they exhibit differing degrees of erosion.
If a short-circuit occurs in the system, check the main contacts and use a screwdriver
to separate any contacts that have become welded together. Replace the damaged
arc chute.

To replace the arc chute

Release the quick fastening:

3TC44: Press the two bolts (1) in with a screwdriver and turn them 90°. The arc

chute (2) can then be lifted off.

3TC48, 3TC52, 3TC56: Press the bolt (3) of the blowout unit (4) in with a

screwdriver and turn it 90°. Swing out the blowout unit, then press the two bolts (1)
in with a screwdriver and turn them 90°. The arc chute (2) can then be lifted off.
To fasten:
Mount the arc chute (2), press the two bolts (1) in as far as they will go and turn them
90°. Then swing in the blowout unit (4) of the 3TC48, 3TC52 or 3TC56, press the bolts
(3) in as far as they will go and turn them 90°.

All

bolts must latch in position!

To replace the main contacts

Lift off the arc chute (see "To replace the arc chute").

Movable contacts:

a 3TC44: Press the contact gently against the contact spring, turn it laterally 90°

and withdraw it. Lift up the spring cup slightly and insert the new contact in the
same way.

a 3TC48, 3TC52, 3TC56: Lift up the spring-loaded bridge support with a

screwdriver and press out the leaf spring. Turn the contact laterally until it can be
withdrawn. Insert the new contact and leaf spring in the same way.
Make sure that they are properly centered and able to move freely!
Fixed contacts:

b 3TC44: Loosen the fixing screw, then replace it together with the contact.

b 3TC48, 3TC52, 3TC56: Replace the contact and fixing screw using a 4 mm

hexagon (Allen) screwdriver (3TC52, 3TC56: 5 mm).
Screw the new contacts on tightly

(tightening torques: Nm,

see

Replace the auxiliary switches

(see Figs.

and

The contactor has two auxiliary switches (5), each with 1 NO and 1 NC contact.
Replace the complete auxiliary switch block if necessary.

To replace the coil

3TC44 with AC operation

Loosen the two fixing screws (1). Lift off the contactor base (2) and the arc chute.
Turn the coil (3) a short distance laterally and take it out of the magnetic chamber (6).
Mount the new coil on the damping springs (7) and press it against these springs so
that it snaps into the pins (8). Insert the stranded wires into the magnetic chamber
and press the coil terminals (4) into the cutouts (9). Screw the contactor base (2)
tightly onto the magnetic chamber (6) again. The centering holes (5) serve to position
the base plate correctly in relation to the contactor base.

3TC44 with DC operation

Loosen the two fixing screws (1). Lift off the contactor base (2) and the arc chute.
Unscrew the countersunk head screws (11) and remove the pole sheets (10).
Withdraw the coil terminals (12) a short distance from the cutouts (13) and take the
coil (14) out of the magnetic chamber (15). Reassemble in reverse order.

3TC48 with AC operation

Loosen the two fixing screws (16) for the base plate (17). Lift off the contactor base
(18) and the arc chute. Replace the coil (19). Mount the contactor base again and
screw the base plate tight.

3TC52, 3TC56 with AC operation

Unscrew the base plate (20). Unscrew the two self-locking screws (21) with a
wrench, then open out the bottom part of the coil assembly (22) with the coil (23).
Insert the new coil so that the terminal markings are visible. Reassemble in reverse
order.

3TC48, 3TC52, 3TC56 with DC operation

Loosen the four fixing screws (24). Lift off the contactor base (25) and the arc chute.
Loosen the screws (27). Lift the pole sheets (26) and the coil (29) off the coil cores
(28) and the base plate (30); replace the coil (29). Reassemble in reverse order.

Make sure the pole faces are clean!

To mount 3TC4417-0C series and economy resistors

3TC44 contactor with coil operating range from 0.7 to 1.2 U

, 0.6 to 1.2 U

0.7 to 1.25 U

or 0.8 to 1.2 U

Tightening torques for:
Resistor fastening

2,5 Nm

Retaining angle on contactor

0,9 Nm

Auxiliary switches and coil terminals

0,9 Nm

Resistor terminals

0,6 Nm

For spare parts

see

Fig. IV

Main contact

Arc chute

Auxiliary switch block, left: 1 NO + 1 NC

Auxiliary switch block, right: 1 NO + 1 NC

Refer to the catalog for more data as well as Order Nos. for accessories. Reliable
functioning of the equipment is only ensured with certified components.

Rated insulation voltage

Rated operating current

(DC 1), see

Fig. V

Max. motor power ratings (DC 2, DC 4)

The performance data indicated on the rating plate applies to 2-pole switching
of the load and to series-connected main circuits.
For operating voltage see coil terminal
Operating range

0.8 to 1.1 x U

Maximum backup fuses

NH fuse (Type 3NA1)

DIAZED fuse link, quick-acting

a No unwanted welding together of the contacts
b Contacts that have become welded together can easily be separated

without any damage

DANGER

Hazardous voltage.
Will cause death or serious
injury.
Disconnect power before
working on equipment.

Mounting

Connection

Operation

Technical specifications

3TC4

3TC5

: 800 V DC U

: 1000 V DC

This product has been designed
for environment A. Use of this
product in enviroment B may
cause unwanted electromegnetic
distrubances in which case the
user may be required to take
adequate mtigation measures.

Notice