Schaltbau C295 Series User manual

33
Contactors
C295 series
Double pole
NO contactors
Installation and maintenance
instructions
Manual B295-M.en

22020-05-13 / V1.0
Contactors C295 – Installation and Maintenance Instructions
Document Revision History
Date Rev. Level Description Pages
2020-05-13 1.0 First release all
Content
1. Important basic information......................................................................................... 4
1.1 Legal notes .............................................................................................................................. 4
1.2 Conventions for this manual............................................................................................. 4
2. General and security information ................................................................................ 4
2.1 Observing the instructions................................................................................................ 4
2.2 User obligations..................................................................................................................... 5
2.3 Intended use........................................................................................................................... 5
2.4 Ambient conditions.............................................................................................................. 5
3. Dangers and security measures.................................................................................... 6
3.1 Electrical dangers.................................................................................................................. 6
3.2 Other dangers ........................................................................................................................ 6
3.3 Measures for avoiding damages and malfunctions ................................................. 7
4. Product information........................................................................................................ 8
4.1 Double pole NO contactor, C295Series........................................................................ 8
4.2 Features .................................................................................................................................... 8
4.3 Applications ............................................................................................................................ 8
4.4 Technical information and material specication..................................................... 8
4.5 Overview .................................................................................................................................. 9
5. Storage.............................................................................................................................10
6. Unpacking.......................................................................................................................10
6.1 Unpack the device ..............................................................................................................10
6.2 Check parts for transport damage................................................................................10
7. Installation ......................................................................................................................11
7.1 Mechanical installation.....................................................................................................11
7.1.1 Dimensions and further technical specications....................................................11
7.1.2 Preliminaries .........................................................................................................................11
7.1.3 Correct mounting positions............................................................................................11
7.1.4 Required minimum clearance .......................................................................................12
7.1.5 Ventilation requirements .................................................................................................12
7.1.6 Safety.......................................................................................................................................12
7.1.7 Required tools ......................................................................................................................12
7.1.8 Install the contactor ...........................................................................................................12

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2020-05-13 / V1.0 Contactors C295 – Installation and Maintenance Instructions
7.2 Electrical installation..........................................................................................................13
7.2.1 Electrical data and further technical specications................................................13
7.2.2 Preliminaries .........................................................................................................................13
7.2.3 Safety.......................................................................................................................................13
7.2.4 Required tools ......................................................................................................................14
7.2.5 Connect the auxiliary contacts.......................................................................................14
7.2.6 Connect the coil terminals...............................................................................................15
7.2.7 Connect the main contacts .............................................................................................15
Main contact connection with cables .........................................................................15
Main contact connection with busbars ......................................................................16
7.3 Checks .....................................................................................................................................17
8. Maintenance...................................................................................................................18
8.1 Safety.......................................................................................................................................18
8.2 Preventive maintenance...................................................................................................18
8.2.1 Intervals for regular checks..............................................................................................18
8.2.2 Regular check activities ....................................................................................................19
8.3 Corrective maintenance ...................................................................................................20
8.3.1 Replace the auxiliary contacts........................................................................................20
Required spare parts..........................................................................................................20
Required tools ......................................................................................................................20
Disassembly ..........................................................................................................................20
Assembly................................................................................................................................21
8.3.2 Check the main contacts..................................................................................................21
Preliminaries .........................................................................................................................21
Required tools ......................................................................................................................21
Check the main contacts for wear and tear...............................................................21
8.3.3 Replace the complete contact unit ..............................................................................23
Required spare parts..........................................................................................................23
Required tools ......................................................................................................................23
Disassembly ..........................................................................................................................23
Assembly................................................................................................................................23
8.3.4 Replace the magnetic drive.............................................................................................24
Required spare parts..........................................................................................................24
Required tools ......................................................................................................................24
Disassembly ..........................................................................................................................24
Assembly................................................................................................................................24
9. Spare parts......................................................................................................................25
10. Technical data.................................................................................................................26
11. Disposal ...........................................................................................................................26

42020-05-13 / V1.0
Important basic information
Contactors C295 – Installation and Maintenance Instructions
1. Important basic information
1.1 Legal notes
Without prior written consent of Schaltbau GmbH, this
manual is not allowed to be electronically or mechani-
cally reproduced – as a whole or in parts – be distrib-
uted, changed, transmitted, translated into another
language or used in any other way.
Schaltbau GmbH cannot be held liable for damage
caused by not observing (or only partly observing) the
manual.
1.2 Conventions for this manual
This manual describes the installation and maintenance
of the contactors.
Cross references are presented in bold italics.
To highlight particularly important safety instructions
and other information, the following symbols are used
in this instructions:
DANGER
Indicates a hazardous situation with a high level
of risk which, if not avoided, will result in death or
serious injury.
WARNING
Indicates a hazardous situation with a medium level
of risk which, if not avoided, could result in death or
serious injury.
CAUTION
Indicates a hazardous situation with a low level of
risk which, if not avoided, may result in minor or
moderate injury.
NOTICE
Indicates a hazardous situation which, if not avoided,
may result in property damage, such as service inter-
ruption or damage to equipment or other materials.
Refers to technical features and methods
aimed at facilitating work or to particu-
larly important information.
This manual refers to double pole NO contactors of the
C295 series
This manual describes only stock items of the above
mentioned contactor types. If you need a special vari-
ant feel free to contact us.
2. General and security information
The contactors dealt with in this document are in-
tended for use with electrical systems for special instal-
lations. They are designed and tested in compliance
with the generally recognised state of the art. However,
improper use, operation, handling, maintenance of or
tampering with electric equipment can cause serious
or fatal injury to the user or others, and the appliance or
other property can be damaged.
The operation, maintenance and installation instruc-
tions for the contactors must therefore be strictly fol-
lowed.
Any uncertainties must be claried and all queries must
include details of the type of device and the serial num-
ber.
Only authorized and trained personnel are allowed to
plan and carry out all mechanical and electrical installa-
tions, transport, commissioning, as well as maintenance
and repair work.
This applies to the observation of the general installation
and safety regulations for work on electrical systems as
well as the proper use of tools approved for this purpose.
Electrical equipment requires protection from moisture
and dust during installation, operation or storage.
2.1 Observing the instructions
X All sta must read and understand the instructions
in this manual and adhere to them when working
with the device.
X Always carefully observe all safety warnings!

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2020-05-13 / V1.0 Contactors C295 – Installation and Maintenance Instructions
General and security information
2.2 User obligations
X Observe all applicable national provisions, all safe-
ty, accident prevention and environmental regula-
tions as well as the recognized technical rules for
safe and proper working.
X Carry out regular inspections of all protection and
safety devices to see if they work properly.
X Work on electric equipment may only be per-
formed by an expert or trained personnel working
under the direction and supervision of an expert
according to the applicable rules of electrical en-
gineering.
X An expert is a person who can judge and recognise
the possible dangers of the jobs assigned to him
based on his training, knowledge and experience
and by knowledge of the appropriate regulations.
X Work on the contactors must only be carried out
by sta who meets the requirements set out in this
manual.
X Sta must be informed clearly about who is re-
sponsible for the maintenance of the contactors.
X After each installation work and/or after any other
modications, alterations or maintenance works,
always perform complete checks according to
these standards:
-EN/IEC 60077-2
-EN/IEC 60947-4-1
2.3 Intended use
X The contactors have been designed and tested ac-
cording to national and international standards.
Due to their unique features they can also be used
in a variety of applications.
X The contactors must only be used under operating
conditions according to the technical specication
and the instructions in this manual.
X None of the operating conditions dened in the
corresponding data sheets and in our catalogue
B295 in section “Specications“, such as volt-
ages, currents, ambient conditions, etc. may be
changed. The catalogue is available under:
https://www.schaltbau.com/en/media-library/
X The contactors may only be used when all protec-
tive devices are present, have been installed prop-
erly and are fully operational.
X The contactors must not be contaminated with
aggressive media.
X Contactors may not be used without further pro-
tective measures in potentially explosive atmos-
pheres.
X The contactor meets the requirements of basic in-
sulation. Make sure the frame or plate onto which
the drive of the contactor is mounted is earthed in
a shock and vibration resistant way.
X Coil suppression for reducing surges when the coil
is switched o is optimally attuned to the contac-
tor‘s switching behaviour. The existing opening
characteristic must not be negatively inuenced
by parallel connection with an external diode.
X The contactor has unprotected live parts
X The required clearance of live parts to earth and
other parts of the contactor is to be observed as
well as the safety regulations of the applicable
standards.
X Switching at maximum breaking capacity might
require larger clearance! Do not hesitate to ask our
advice for dimensioning.
X Improper handling of the contactors, e.g. when
hitting the oor with some impact, can result in
breakage, cracks and deformation. Always handle
the contactors with care.
X Use the contactor only according to its intended
use. Replace or repair damaged parts exclusively
with original parts. Any other usage of or tamper-
ing with the contactors is considered contrary to
its intended use. No liability is assumed for damag-
es and accidents caused due to non-compliance
with the instructions in this manual or improper
use of the contactors.
2.4 Ambient conditions
NOTICE
The contactors are constructed for specic ambient
conditions.
X Operate the contactors only according to the
ambient conditions, like temperature ranges,
pollution degree, etc., as dened in the cor-
responding data sheets and in our catalogue
B295. The catalogue is available under:
https://www.schaltbau.com/en/media-library/

62020-05-13 / V1.0
Dangers and security measures
Contactors C295 – Installation and Maintenance Instructions
3. Dangers and security measures
3.1 Electrical dangers
DANGER
The contactors are used to switch voltage. The touching of electrically conducting parts may result
in serious injuries or even death!
Energized parts are all metal parts belonging directly to one of the circuits or wires leading there. All
other visible metal parts and wires may also be energized in the case of a failure.
Before beginning any work on the contactors, always observe the following safety regulations:
X Disconnect on all sides
X Ensure that it is not possible to reconnect unintentionally
X Clearly mark your work area
X Make sure that there is no voltage present
X Earth and short circuit the installation; this also includes the discharging of any capacitors in
the main circuit
X Besides the main electric circuit, also disconnect additional and auxiliary circuits
X Cover or insulate adjacent energized parts
X Only an electrically skilled person may determine if there is no voltage present
X When the work has been concluded, proceed the other way round.
3.2 Other dangers
WARNING
Exclusively use the contactors for purposes as indicated in the specications and data sheets.
A wrong application can cause accidents and severe damages to persons!
X The manufacturer doesn‘t take the responsibility for accidents which were caused by improper
use of the product.
CAUTION
During continuous operation the contactors may become hot. Risk of burns!
X Before beginning any checks or maintenance work on the contactors make sure that the heat-
ed components have cooled down.
CAUTION
The contactors contain sharp-edged parts. Risk of injury!
X Use appropriate tools for installation and maintenance works on the contactors.
X Wear protective gloves when working with sharp-edged components.

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Dangers and security measures
3.3 Measures for avoiding damages and malfunctions
NOTICE
Aggressive uids may damage the contactors.
X Make sure that the contactors are not exposed to aggressive uids.
NOTICE
Improper handling of the contactors, e.g. when hitting the oor with some impact, can result in breakage, cracks
and deformation.
X Make sure that the contactors are always used properly.
X Do not throw the contactors to the oor.
X Regularly sight-check the contactors for potential damages.
X Immediately replace damaged components.
NOTICE
Depending on the product type, contactors can contain strong (permanent) magnets. These magnets can attract
ferromagnetic particles and may damage the contactors.
X Make sure that the contactors are installed at a location, where no ferromagnetic particles can be attracted.
NOTICE
Depending on the product type, contactors can contain strong (permanent) magnets. These magnets can de-
stroy data on credit cards or similar cards.
X Keep credit cards or similar cards away from the contactors..
NOTICE
During the switching o, strong electromagnetic elds are generated in the surroundings of the contactors.
These may inuence other components close to the contactors.
X Make sure that the contactors are installed at a location, where no other components can be aected.
NOTICE
In the case of damage, wear and tear and/or soiling of the contactor components - in the form of a partial break,
sharp edges and discoloured surfaces - the functional safety of the contactors is no longer guaranteed.
X Carry out regular visual checks to detect wear and tear and dirt.
X Immediately replace damaged parts.
X Immediately remove dirt without leaving any residues.
X Immediately replace parts with stubborn dirt.
NOTICE
Detent-edged rings and detent-edged washers have a limited life time. After 3 times opening of screws secured
with detent-edged rings or detent-edged washers, the rings or washers must be replaced by new ones.
X Record the frequency of screw opening in the work log.
X After 3 times opening of screws, replace detent-edged rings or detent-edged washers by new ones..

82020-05-13 / V1.0
Product information
Contactors C295 – Installation and Maintenance Instructions
4. Product information
4.1 Double pole NO contactor,
C295series
Compact double-pole high-voltage NO contactor for
DC and AC
With its compact size and ecient arc chute our C295
Series contactor allows the handling of voltages up to
1,500 V and currents of 120 A max.
Switching high amperage even at signicant induct-
ance can be achieved by series connection of the main
contacts, whereas parallel connection results in longer
contact life.
4.2 Features
X Compact in size
X Double-break contacts
X With magnetic blowout for DC arc quenching
X Switching of high inductive loads by means of
main contacts connected in series
X Parallel connection: Longer life of main contacts
4.3 Applications
Typical applications are to be found in trac engineer-
ing equipment, particularly in heating circuits, air con-
ditioning equipment and conversion engineering of
complex power supplies.
4.4 Technical information and material
specication
For technical information and material specications,
refer to the corresponding data sheets and to our cata-
logue B295. The catalogue is available under:
https://www.schaltbau.com/en/media-library/

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2020-05-13 / V1.0 Contactors C295 – Installation and Maintenance Instructions
Product information
4.5 Overview
F
A
I
G
H
E
H
C
D
E
B
Fig. 1: Overview C295 series
A Auxiliary contacts (2x S870), Terminals: Flat tabs 6.3 x 0.8 mm
B Arc chambers
C Plasma exits
D Permanent magnets
E Main contacts, Terminals: M6, Tightening torque: 6 Nm max.
F Coil suppression: Varistor
G Coil terminals: Cage clamp
H Mounting holes for screws M6, Tightening torque depends on the property class (min. 8.8) of the screws/nuts used
I Base plate

10 2020-05-13 / V1.0
Storage
Contactors C295 – Installation and Maintenance Instructions
5. Storage
NOTICE
Moisture and dust can damage the contactor. If
the device is to be stored for a prolonged period
of time,
► store it in its original packaging,
► store it in a dry and dust-free location.
Return shipments
Schaltbau recommends to keep the original packing
box for any return shipments. If no original packing box
is available care must be taken to pack the contactor in
a way that prevents damage during shipment.
6. Unpacking
6.1 Unpack the device
X Before opening the packaging, perform a visual
inspection for any signs that could indicate dam-
age having occurred during transport (impacts,
bumps, falling etc.).
X If any signs indicate that the contactor has been
subject to excessive shock inuence do not install
the contactor.
6.2 Check parts for transport damage
NOTICE
If parts are damaged, the functional reliability of the
contactor is no longer given.
X Before installing, check all parts for any possible
transport damage.
X Do not install a damaged contactor.

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2020-05-13 / V1.0 Contactors C295 – Installation and Maintenance Instructions
Installation
7. Installation
7.1 Mechanical installation
7.1.1 Dimensions and further technical
specications
The dimensions and further technical specications are
given in the respective data sheets or in our catalogue.
Refer to our catalogue B295.
The catalogue is available under:
https://www.schaltbau.com/en/media-library/
7.1.2 Preliminaries
X An appropriate mounting plate or mounting
frame has to be provided for the fastening of the
device. The mounting plate or frame must be solid
enough to carry the weight of the device under
the expected shock and vibration conditions.
X 3 mounting holes must be prepared on the mount-
ing plate or frame according to Fig. 2.
3x Ø 6.8 or M6
153 ±0.15
42 ±0.1
[mm]
Fig. 2: Dimensions and arrangement of the mounting holes
X The mounting holes can be prepared in two ways:
-either as threaded holes (for threaded screws)
-or as through-holes (for threaded screws and
nuts)
X The contactors are xed to the mounting plate or
frame with 3 mounting screws M6.
-The length of the xing screws has to be deter-
mined according to the constructional condi-
tions.
-In order to secure the mounting screws against
self-loosening, appropriate screw locking ele-
ments have to be provided. Schaltbau strongly
recommends Schnorr-Washers (or similar) to se-
cure the screws.
-The tightening torque depends on the property
class (min. 8.8) of the screws/nuts used.
7.1.3 Correct mounting positions
The contactors can be installed at the prepared mount-
ing plate or frame in almost any installation position.
Examples of intended mounting positions are shown in
Fig. 3.
Not permitted are hanging installation positions with
the mounting plate/mounting frame facing upwards,
as shown for example in Fig. 4.
360°
±90°
±90°
Fig. 3: Examples for intended mounting positions
±90°
±90°
Fig. 4: Examples of not permissible mounting positions

12 2020-05-13 / V1.0
Installation
Contactors C295 – Installation and Maintenance Instructions
7.1.4 Required minimum clearance
NOTICE
Switching electrical currents at high voltages will
produce arcing and plasma may exit out of the arc
chambers. It is essential to observe the minimum
clearance towards earthed and live parts to avoid the
risk of a ash-over.
X The required minimum clearance to all sides and
upwards can be found in our catalogue B295. The
catalogue is available under:
https://www.schaltbau.com/en/media-library/
7.1.5 Ventilation requirements
X The installation space must be adequately venti-
lated, especially if severe shutdowns are expected.
This will allow the plasma to decompose more
quickly and reduce the risk of ashover and cor-
rosion.
7.1.6 Safety
X The installation has to be carried out by qualied
trained personnel.
NOTICE
During installation, ensure that dirt caused by sur-
rounding construction activities does not get into
the contactor.
NOTICE
Detent-edged rings and detent-edged washers have
a limited life time. After 3 times opening of screws
secured with detent-edged rings or detent-edged
washers, the rings or washers must be replaced by
new ones.
X Record the frequency of screw opening in the
work log.
X After 3 times opening of screws, replace detent-
edged rings or detent-edged washers by new
ones.
7.1.7 Required tools
-Socket wrench set, hexagon nuts
-Open-end wrench set
-Hexagon socket wrench set
-Torque wrench
7.1.8 Install the contactor
X Make sure, that the mounting surfaces of the
mounting plate (3) or frame and the lower side of
the contactor are free from dirt and other contami-
nation (e. g. metal cuttings).
X Place the contactor (1) on the mounting plate (3)
or frame provided with the mounting holes.
X Screw the contactor (1) to the mounting plate (3)
or frame using the 3 mounting screws (2).
-If the mounting holes are designed as threaded
holes, screw the screws with suitable screw lock-
ing elements directly into the prepared threads.
-If the mounting holes are through holes, tighten
the screws with suitable screw locking elements
(on both sides) and nuts.
X Then tighten the mounting screws (2) with a
torque depending on the property class (min. 8.8)
of the screws/nuts used.
A1A1
3
2
1
Nm
2 x M6
2
Nm
M6
Fig. 5: Install the contactor to the mounting plate or frame

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2020-05-13 / V1.0 Contactors C295 – Installation and Maintenance Instructions
Installation
7.2 Electrical installation
7.2.1 Electrical data and further
technical specications
For the power consumption of the magnetic drive sys-
tem and electrical data of the auxiliary switches refer to
the respective data sheets and to our catalogue B295.
The catalogue is available under:
https://www.schaltbau.com/en/media-library/
7.2.2 Preliminaries
X The connection of the main current circuit can be
done with wires or busbars.
X If wires are used, the wire gauges must be selected
in coordination with their insulation class and the
ambient conditions.
X The minimum cross sections for the conventional
thermal current Ith of the connection cables/bus-
bars are specied in our catalogue B295 and must
be observed. The catalogue is available under:
https://www.schaltbau.com/en/media-library/
X The cables of the main current circuit must be t-
ted with appropriate ring cable lugs (for terminal
screws M6).
X Schaltbau recommends Schnorr-Washers (or simi-
lar) to secure the terminal screws against self-loos-
ening.
X The terminal screws must be tightened with a
torque of 6 Nm.
X The terminals of the the auxiliary contacts are
designed as at tabs. Therefore the control wires
must be tted with appropriate blade receptacles
(6.3 x 0.8mm) for tabs.
X The maximum permissible cross section of the
auxiliary contact control cables is 1 mm2/ AWG 18
stranded wire.
X The control wires for the coil connection are con-
nected with cage clamp terminals and must be
stripped accordingly.
7.2.3 Safety
DANGER
The contactors are used to switch voltage. The touching of electrically conducting parts may result
in serious injuries or even death!
Energized parts are all metal parts belonging directly to one of the circuits or wires leading there. All
other visible metal parts and wires may also be energized in the case of a failure.
Before beginning any work on the contactors, always observe the following safety regulations:
X Disconnect on all sides
X Ensure that it is not possible to reconnect unintentionally
X Clearly mark your work area
X Make sure that there is no voltage present
X Earth and short circuit the installation; this also includes the discharging of any capacitors in
the main circuit
X Besides the main electric circuit, also disconnect additional and auxiliary circuits
X Cover or insulate adjacent energized parts
X Only an electrically skilled person may determine if there is no voltage present
X When the work has been concluded, proceed the other way round.
NOTICE
Detent-edged rings and detent-edged washers have a limited life time. After 3 times opening of screws secured
with detent-edged rings or detent-edged washers, the rings or washers must be replaced by new ones.
X Record the frequency of screw opening in the work log.
X After 3 times opening of screws, replace detent-edged rings or detent-edged washers by new ones.

14 2020-05-13 / V1.0
Installation
Contactors C295 – Installation and Maintenance Instructions
7.2.4 Required tools
-Socket wrench set, hexagon nuts
-Open-end wrench set
-Torque wrench
-Continuity tester
-Cable ties
7.2.5 Connect the auxiliary contacts
NOTICE
Make sure that according to the insulation coordina-
tion there is sucient clearance between the wires
of the control voltage and the main connections.
NOTICE
X The maximum permissible cross section of the
auxiliary contact control wires is 1 mm2/ AWG 18
stranded wire.
X Bending of the auxiliary contact terminals is not
permissible!
X Move and lay the control wires and blade re-
ceptacles only in plugging direction, see Fig. 6.
X Secure the control wires mechanically, in order
to minimize eects of cable forces (e. g. shock,
vibrations) to the terminals.
The control wires for the auxiliary contacts must be t-
ted with appropriate blade receptacles (6.3 x 0.8 mm).
X Plug the prepared control wires with the blade
receptacles (1) to the terminals (2) of the auxiliary
contacts.
X If necessary, bundle and x the cables with cable
ties.
6.3 x 0.8 mm
1
6.3 x 0.8 mm
1
2
Fig. 6: Connect the S870 auxiliary contacts

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2020-05-13 / V1.0 Contactors C295 – Installation and Maintenance Instructions
Installation
7.2.6 Connect the coil terminals
NOTICE
The value of the overvoltage limitation is part of the
magnetic system and must not be changed and in
particular must not be short-circuited (e. g. by an ex-
ternal diode).
X Make sure that no such diode is used in your
control system.
NOTICE
Secure the control wires mechanically, in order to
minimize eects of cable forces (e. g. shock, vibra-
tions) to the terminals.
NOTICE
Make sure that according to the insulation coordina-
tion there is sucient clearance between the wires
of the control voltage and the main connections.
The control wires for the coil connection are connected
with cage clamp terminals and must be stripped ac-
cordingly.
X Connect the prepared stripped control wires (4) to
the cage clamp terminals (5) on the terminal block
(5).
X Check that the cables are rmly xed.
X If necessary, bundle and x the cables with cable
ties.
5
4
Fig. 7: Connect the coil terminals
7.2.7 Connect the main contacts
NOTICE
Make sure, that the connection points of the main
contacts are free from corrosion.
Main contact connection with cables
The wires of the main current circuit must be tted with
appropriate ring cable lugs (for terminal screws M6).
An Example of the connection with cables is shown in
Fig. 8.
X Lay the prepared connection cables (3) to the
main contacts (1).
X Place the ring cable lugs (2) on the main contacts
(1).
NOTICE
Make sure that according to the insulation coordina-
tion there is sucient clearance between the main
terminals and the pole plates.
X Screw the ring cable lugs (2) to the main contacts
(1) using the terminal screws (4) and washers (5).
-Schaltbau recommends Schnorr-Washers (or
similar) to secure the terminal screws.
X Tighten the terminal screws (4) with a torque of
max. 6 Nm.
max. 6
Nm
max. 6
Nm
4
5
3
2
13
2
1
4
5
Fig. 8: Connect the main contacts (example for the connec-
tion with cables)

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Installation
Contactors C295 – Installation and Maintenance Instructions
Main contact connection with busbars
As an alternative to the connection with cables, the
main circuit can also be connected with busbars.
Examples for the connection with busbars are shown in
Fig. 9 to Fig. 11.
X Lay the busbars (7) to the main contacts (1).
NOTICE
Make sure that according to the insulation coordina-
tion there is sucient clearance between the main
terminals and the pole plates.
X Depending on the installation situation, use ad-
ditional connecting bars (6) or angled connecting
bars (8) if necessary.
X Connect the busbars (7) to the connecting bars
(6) or angled connecting bars (8) using approriate
screws and washers.
-Schaltbau recommends Schnorr-Washers (or
similar) to secure the screws.
X Connect the connecting bars (6) or angled con-
necting bars (8) to the main terminals (1) using the
terminal screws (4) and washers (5).
-Schaltbau recommends Schnorr-Washers (or
similar) to secure the screws.
X Tighten the terminal screws (4) with a torque of
max. 6 Nm.
max. 6
Nm
max. 6
Nm
4
5
6
11
4
5
77
6
Fig. 9: Connect the main contacts (example for the connec-
tion with busbars (7) and connecting bars(6))
max. 6
Nm
max. 6
Nm
4
5
8
11
4
5
77
8
Fig. 10: Connect the main contacts (example of parallel con-
nection with busbars (7) and angled connecting bars
(8))
max. 6
Nm
max. 6
Nm
4
5
6
1
7
1
4
5
7
9
Fig. 11: Connect the main contacts (example for series con-
nection with with busbars (7), connecting bars (6) and
contact bridge (9))

17
2020-05-13 / V1.0 Contactors C295 – Installation and Maintenance Instructions
Installation
7.3 Checks
After the installation is completed, do the following
checks:
X Check that the contactors are correctly installed
on the mounting plate/frame and t tightly.
X Check that the cables or busbars are correctly in-
stalled and t tightly at the main contacts.
X Check that the control wires of the coil terminals
are correctly installed.
X Check that the control wires are properly connect-
ed to the auxiliary switches.
Use a continuity tester to check that the wiring is
correct and the auxiliary switches are functioning
correctly.
X Switch the contactor several times without load.
X Perform a functional test (undervoltage, dropp-o
voltage of the contactor) according to Schaltbau
requirements. Refer to catalogue B295.
X Check the laying of cables. Cables must not be
squeezed or bent. If applicable bundle and secure
with cable ties.
X After each installation and after maintenance
works, always perform complete checks according
to these standards:
-EN/IEC 60077-2
-EN/IEC 60947-4-1

18 2020-05-13 / V1.0
Maintenance
Contactors C295 – Installation and Maintenance Instructions
8. Maintenance
Note the expert knowledge which is essential for car-
rying out maintenance work, mentioned in chapter
“2. General and security information”.
8.1 Safety
DANGER
The contactors are used to switch voltage. The touching of electrically conducting parts may result
in serious injuries or even death!
Energized parts are all metal parts belonging directly to one of the circuits or wires leading there. All
other visible metal parts and wires may also be energized in the case of a failure.
Before beginning any work on the contactors, always observe the following safety regulations:
X Disconnect on all sides
X Ensure that it is not possible to reconnect unintentionally
X Clearly mark your work area
X Make sure that there is no voltage present
X Earth and short circuit the installation; this also includes the discharging of any capacitors in
the main circuit
X Besides the main electric circuit, also disconnect additional and auxiliary circuits
X Cover or insulate adjacent energized parts
X Only an electrically skilled person may determine if there is no voltage present
X When the work has been concluded, proceed the other way round.
8.2 Preventive maintenance
Contactors of the C295 series are maintenance-free
within the rated mechanical life time. The electrical
life time depends on the number of switchings under
heavy load conditions and may vary for dierent ap-
plications. In normal use, this corresponds to a decade-
long operating period.
8.2.1 Intervals for regular checks
To ensure the correct function and a prolonged opera-
tional life span of the contactors, the following checks
and maintenance must be performed regularly.
Checks Interval
Visual inspection of the contactor
from outside
X 1x per year
Inspection of the main contacts
X Every 2years
Inspection of the auxiliary switches
X Every 2years
If the contactors are operated in particularly dirty envi-
ronments, the checking intervals for visible inspections
should be shortened, because dirt can impair the insu-
lation clearances and there is therefore the possibility
of a shorter service life or an operational fault.
Unscheduled checks are only necessary if there has
been a signicant number of switching operations un-
der overload and short circuit conditions.
DANGER
When damages on the contactor, cables
or busbars are visible, the safety of the
contactor is no longer guaranteed.
X Immediately give damaged con-
tactors or components to correc-
tive maintenance.
NOTICE
Detent-edged rings and detent-edged washers have
a limited life time. After 3 times opening of screws
secured with detent-edged rings or detent-edged
washers, the rings or washers must be replaced by
new ones.
X Record the frequency of screw opening in the
work log.
X After 3 times opening of screws, replace detent-
edged rings or detent-edged washers by new
ones.

19
2020-05-13 / V1.0 Contactors C295 – Installation and Maintenance Instructions
Maintenance
8.2.2 Regular check activities
All of the maintenance activities that may be carried out
on the contactors by skilled personnel are listed below.
Component Visual inspection Measures
Cables/busbars Check for:
X broken cables, cable lugs
X damaged insulation
X kinked or crushed cables
X damaged busbars
X loose or missing fastening elements
X correct tightening torque of the terminal screws
In case of faults:
X immediately replace damaged cables
or cable lugs
X immediately replace damaged bus-
bars
X thighten loose fastening elements
immediately replace missing fasten-
ing elements
X thighten the terminal screws with
the rated torque
Auxiliary contacts Check for:
X dirt
X damage or wear on the housing
X signs of short circuits
The auxiliary contact is visible for a simple optical
inspection from the outside.
Under normal working conditions (if there were
no short circuits in the control circuit) the life time
of the auxiliary contacts exceeds that of the con-
tactor many times over.
In case of faults:
X replace the auxiliary contacts, refer
to section “8.3 Corrective mainte-
nance”/ “8.3.1 Replace the auxiliary
contacts”.
Contactor housing Check for:
X dirt
X damage or wear and tear
X penetrations, holes in the contactor housing wall
X loose or missing fastening elements
In case of faults:
X remove existent dirt
X if the contactor housing is damaged
or heavily worn replace the complete
contactor unit, see section „8.3 Cor-
rective maintenance“ / „8.3.3 Replace
the complete contact unit“.
X in case of penetrations, holes in the
contactor housing wall replace the
complete contactor unit, see section
„8.3 Corrective maintenance“ / „8.3.3
Replace the complete contact unit“.
X thighten loose fastening elements
and immediately replace missing fas-
tening elements
X thighten a loose contactor
Main contacts
(both, xed contacts
and movable contact
bridge)
Contact unit com-
plete
To test the main contacts, the complete contact unit
must rst be removed, see section “8.3 Corrective
maintenance”/”8.3.2 Check the main contacts”
The main contacts are then accessible and can be
checked for:
X damage or wear and tear
X traces of burn-o (slight sooting permissible)
It requires some experience to evaluate the state of
the contacts. Even after only a few switchings under
load the contacts look used and “polluted”for the
inexperienced eye. The main contacts only need to be
replaced when the minimum height of the contact tip
is less than 0.7 mm (new condition 1.5 mm).
In case of faults:
X if the contact material on one of the
contacts on the contact bridge or on
the xed contacts has burned away
to less than 0.7 mm minimum height,
replace the complete contact unit,
see section „8.3 Corrective mainte-
nance“ / „8.3.3 Replace the complete
contact unit“.

20 2020-05-13 / V1.0
Maintenance
Contactors C295 – Installation and Maintenance Instructions
Component Visual inspection Measures
Magnetic drive unit Check for:
X dirt
X damage or heavy wear and tear
X damage due to operation with impermissible, too
high coil voltage
In case of faults:
X if damaged or heavily worn, replace
the complete magnetic drive unit,
see section “8.3 Corrective mainte-
nance” / „8.3.4 Replace the magnetic
drive“.
8.3 Corrective maintenance
The contactors are maintenance-free. There is therefore
no general need to replace parts during their service
life.
However, if an excessive number of emergency shut-
downs or damage has occurred during operation,
Schaltbau oers original spare parts.
WARNING
The use of unsuitable parts can lead to
accidents and serious personal injury
due to malfunctions.
X Only use original spare parts!
X Do not combine single parts from
dierent contactors!
8.3.1 Replace the auxiliary contacts
Under normal working conditions (if there were no
short circuits in the control circuit) the life time of the
auxiliary contacts exceeds that of the contactor many
times over.
However, in case of a short circuit in the control circuit it
can happen that the auxiliary contacts have been dam-
aged and must be replaced.
Required spare parts
-Auxiliary contact assembly (2 auxiliary contacts with
self-tapping screws), see chapter „9. Spare parts“.
Required tools
-Phillips screwdriver set
-Torque wrench
-Continuity tester
Disassembly
DANGER
Before beginning any work on the con-
tactors, make sure that
X there is no voltage present,
X all safety regulations are fully ob-
served.
X Refer also to section“8.1 Safety”.
NOTICE
The auxiliary contacts are printed dierently. Incor-
rect installation of the auxiliary contacts leads to
malfunctions and can destroy the contactor.
X Before disassembly, note the position of the
contact numbering on the labels of the auxiliary
contacts.
X Disconnect the control wires from the auxiliary
contacts.
X Loosen and remove the self-tapping screws (1) on
the auxiliary contacts (2).
X Remove the auxiliary contacts (2) from the upper
part of the contactor.