KNF N838 DC Series User manual

N838_DC
TRANSLATION OF ORIGINAL
OPERATING AND INSTALLATION
INSTRUCTION
ENGLISH
KNF 347395-347606 09/23
OEM
Notice!
Before operating the pump and accessories, read and observe the operat-
ing and installation instructions as well as the safety information!
DIAPHRAGM PUMP
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Contents
1 About this document ............................................................................. 3
1.1 Using the operating and installation instructions........................... 3
1.2 Exclusion of liability....................................................................... 3
1.3 Symbols and markings.................................................................. 4
2 Safety .................................................................................................... 6
2.1 Personnel and target group .......................................................... 6
2.2 Responsibility of the operator ....................................................... 7
2.3 Working in a safety conscious manner ......................................... 7
2.4 Operating conditions ..................................................................... 8
2.5 Media ............................................................................................ 8
2.6 Use................................................................................................ 9
2.7 Directives and standards ............................................................ 10
2.8 Customer service and repair....................................................... 11
2.9 Disposal ...................................................................................... 11
3 Technical data..................................................................................... 12
3.1 Technical data............................................................................. 12
4 Product description ............................................................................. 14
5 Transport............................................................................................. 16
General ....................................................................................... 16
6 Installation and connection.................................................................. 18
6.1 Installing the pump...................................................................... 18
6.2 Electrical connection ................................................................... 21
6.3 Pneumatic connection................................................................. 23
7 Operation ............................................................................................ 25
7.1 General ....................................................................................... 25
7.2 Information on switching the pump on and off ............................ 28
8 Servicing ............................................................................................. 29
8.1 Servicing schedule...................................................................... 29
8.2 Cleaning...................................................................................... 30
8.3 Replacing the diaphragm and valve plates ................................. 31
9 Spare parts and accessories............................................................... 41
9.1 Spare parts ................................................................................. 41
9.2 Accessories................................................................................. 42
10 Troubleshooting .................................................................................. 43
11 Returns................................................................................................ 47

Diaphragm pump N838_DC About this document
Translation of Original Operating and Installation Instruction, KNF 347395-347606
09/23
3
1 About this document
1.1 Using the operating and installation
instructions
The operating and installation instructions are part of the
pump.
àIn the event of uncertainties with regard to the content of
the operating and installation instructions, please contact
the manufacturer (contact data: see www.knf.com).
Please have the type and serial number of the pump
ready.
àRead the operating and installation instructions before you
commission the pump.
àGive the operating and installation instructions only com-
pletely and unchanged to the next owner.
àKeep the operating and installation instructions within
reach at all times.
Project pumps For customer-specific project pumps (pump models that begin
with "PJ" or "PM"), there may be deviations from these oper-
ating and installation instructions.
àFor project pumps, also observe the agreed specifica-
tions.
Optional con-
tents
Project-specific options may be included in the operating and
assembly instructions. These are marked with "Optional". It is
also possible that project-specific deviations are not included
in the operating and assembly instructions.
1.2 Exclusion of liability
The manufacturer assumes no liability for damages and mal-
functions resulting from failure to observe the operating and
installation instructions.
The manufacturer assumes no liability for damages and mal-
functions resulting from changes or modifications to the de-
vice and improper handling.
The manufacturer assumes no liability for damages and mal-
functions resulting from impermissible spare parts and acces-
sories.
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About this document Diaphragm pump N838_DC
4Translation of Original Operating and Installation Instruction, KNF
347395-347606 09/23
1.3 Symbols and markings
Warning notice
WARNING
A notice that warns you of danger is lo-
cated here.
Possible consequences of a failure to
observe the warning notice are speci-
fied here. The signal word, e.g., Warn-
ing, indicates the danger level.
àMeasures for avoiding the danger
and its consequences are speci-
fied here.
Danger levels
Signal word Meaning Consequences if
not observed
DANGER warns of immediate
danger
Death or serious in-
jury or serious
damage will result.
WARNING warns of possible
danger
Death, serious in-
jury or serious
damage is possi-
ble.
CAUTION warns of a possibly
dangerous situation
Minor injury or
damage is possi-
ble.
NOTICE Warns of possible
damage
Damage is possi-
ble.
Tab.1: Danger levels
Other notices and symbols
àAn activity to be carried out is specified here (a step).
1. The first step of an activity to be carried out is specified
here.
Other sequentially numbered steps follow.
This symbol indicates important information.

Diaphragm pump N838_DC About this document
Translation of Original Operating and Installation Instruction, KNF 347395-347606
09/23
5
Explanation of pictograms
Pictogram Meaning
General warning symbol
Warning of hot surface
Warning of electrical voltage
Warning of poisonous substances
Warning of hand injuries through crushing
Observe the operating instructions
General mandatory sign
Use hand protection
Tab.2: Explanation of pictograms
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Safety Diaphragm pump N838_DC
6Translation of Original Operating and Installation Instruction, KNF
347395-347606 09/23
2 Safety
Observe the safety notices in Chapters 6 Installation and
connection [}18] and 7 Operation [}25].
2.1 Personnel and target group
Personnel Make sure that only specially trained and instructed personnel
work on the pumps. This applies, in particular, to mounting,
connection and servicing work.
Make sure that the personnel have read and understood the
operating instructions, particularly the chapter on safety.
Target group Target group Definition
User Employee
Specialized personnel Specialized personnel are
personnel who
- have relevant professional
training in the field covered in
the particular section of text;
- have current knowledge of
the field covered in the partic-
ular section of text.
Tab.3: Target group
Who-does-what
matrix
Lifecycle phase User Specialized per-
sonnel
Transport X
Mounting X
Connection X
Commissioning X X
Operation X X
Servicing X
Troubleshooting X
Disposal X
Tab.4: Who-does-what matrix

Diaphragm pump N838_DC Safety
Translation of Original Operating and Installation Instruction, KNF 347395-347606
09/23
7
2.2 Responsibility of the operator
The pumps are produced in accordance with the generally
recognized rules of engineering, as well as the occupational
health, safety and accident prevention regulations. Neverthe-
less, dangers can arise during their use that lead to injuries to
the user or third parties or to damage to the pump or other
property.
Only use the pumps in perfect technical condition, for their in-
tended use, safely and with an awareness of the dangers and
in observation of the operating and installation instructions.
The components that are to be connected to the pumps must
be designed according to the pneumatic data of the pumps.
When connecting the pumps to the electrical power, observe
the corresponding safety rules.
Make sure that no hazardous situation, physical harm or im-
pairment of the pump can occur.
Operating
parameters
Only operate and install the pump under the operating param-
eters and operating conditions described in Chapters 2.4 Op-
erating conditions [}8] and 3 Technical data [}12].
2.3 Working in a safety conscious manner
Observe the regulations on accident prevention and safety
during all work on the pumps and during operation.
Avoid contact with the pump heads and housing parts be-
cause the pump heats up during operation.
When working on the pump, make sure that the pump is dis-
connected from mains and without power.
When connecting the pump to the electrical mains, observe
the corresponding safety rules.
Ensure that no hazards arise from gas flowing when gas con-
nections are open, from the effects of noise or from hot, corro-
sive, dangerous and environmentally hazardous gases.
Make sure that an EMC-compliant installation of the pump is
ensured at all times to prevent the occurrence of dangerous
situations.
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Safety Diaphragm pump N838_DC
8Translation of Original Operating and Installation Instruction, KNF
347395-347606 09/23
2.4 Operating conditions
Only use the pump in perfect technical condition, for its in-
tended purpose, safely and with an awareness of the dangers
and in observation of the operating instructions.
Only install and operate the pumps in accordance with the op-
erating parameters and conditions described in Chapter 3
Technical data [}12].
Only pumps that are fully assembled and in the condition as
delivered may be operated.
Make sure that the installation location is dry and that the
pump is protected from rain, splash water, gushing water,
dripping water and other contamination.
Check the tightness of the connections between the pipes of
the application and the pump (or the connection of the pump)
at regular intervals. Leaky connections carry the risk of re-
leasing dangerous gases and vapors from the pump system.
2.5 Media
Requirements of
pumped media
Before transferring a medium, check whether the medium can
be transferred without risk in the specific application.
Take note of any change in the state of matter (condensation,
crystallization).
Before using a medium, check the compatibility of the media-
contacting components (see 3 Technical data [}12]) with the
medium.
Risk of dangerous gas mixtures during pump operation if di-
aphragm breaks: Depending on the medium being trans-
ferred, breakage of the diaphragm can result in a dangerous
mixture if the medium mixes with the air in the compressor
housing or the surroundings.
Only transfer gases that remain stable under the pressures
and temperatures that arise in the pump.
Handling of
hazardous
media
Upon breakage of the diaphragm and/or leaks, the transferred
medium mixes with the air in the surroundings and/or in the
pump housing.
Make sure that a dangerous situation cannot arise as a result.
When pumping hazardous media, observe the safety regula-
tions for the handling of said media.

Diaphragm pump N838_DC Safety
Translation of Original Operating and Installation Instruction, KNF 347395-347606
09/23
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Handling of com-
bustible media
Note that the pump is not designed to be explosion-proof.
Make certain that the temperature of the medium is always
sufficiently below the ignition temperature of the medium so
as to prevent ignition or explosion. This also applies for ab-
normal operating situations.
Note that the temperature of the medium increases when the
pump compresses the medium.
Therefore, make certain that the temperature of the medium
also remains sufficiently below the ignition temperature of the
medium even when it is compressed to the maximum permis-
sible operating pressure of the pump. The maximum permissi-
ble operating pressure of the pump is stated in Chapter 3
Technical data [}12].
Make certain that the permissible ambient temperature (see 3
Technical data [}12]) is not exceeded.
Where applicable, also take into account external energy
sources (such as radiated heat sources) that could addition-
ally heat the medium.
In case of doubt, contact KNF Customer Service.
2.6 Use
2.6.1 Proper use
The pumps are intended exclusively for transferring gases
and vapors.
The pumps are intended exclusively for operation in indoor ar-
eas and in non-explosive atmospheres.
2.6.2 Foreseeable misuse
The pumps must not be operated in explosive atmospheres.
The pumps are not suitable for transferring the following:
§Dusts
§Liquids
§Aerosols
§Biological and microbiological substances
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Safety Diaphragm pump N838_DC
10 Translation of Original Operating and Installation Instruction, KNF
347395-347606 09/23
§Fuels
§Explosives and flammable materials
§Fibers
§Oxidizing agents
§Foodstuffs.
As standard, the pumps must not be used for simultaneous
generation of a vacuum and positive pressure.
This function can be made possible on a project basis follow-
ing consultation with KNF Customer Service.
Do not apply positive pressure to the inlet of the pump.
This function can be made possible on a project basis follow-
ing consultation with KNF Customer Service.
2.7 Directives and standards
EU/EC
Directives
Installation declaration – for partly completed machinery
With respect to the Machinery Directive 2006/42/EC, the
pumps are partly completed machinery and are, therefore, to
be regarded as not ready for use. Partly completed machinery
may not be commissioned until it has been determined that
the machine into which the partly completed machinery is to
be installed complies with the provisions of the Machinery Di-
rective 2006/42/EC. The following fundamental requirements
of Annex I of Directive 2006/42/EC (general principles) are
applied and observed:
§General principles no. 1
§No. 1.1.2. / 1.1.3. / 1.3.1. / 1.3.3. / 1.3.4. / 1.4.1. / 1.5.8. /
1.5.9. / 1.7.4. / 1.7.4.1. / 1.7.4.3.
Standards The following standards apply:
§EN IEC 61000-6-1
§EN 60034-1
§EN IEC 55014-1/2
§EN IEC 63000
The protective goals of the following directive(s) are achieved:

Diaphragm pump N838_DC Safety
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§Directive 2011/65/EU on the restriction of the use of cer-
tain hazardous substances in electrical and electronic
equipment (Annex II changed by delegated Directive (EU)
2015/863 of the Commission)
2.8 Customer service and repair
Customer ser-
vice and repairs
The pump is maintenance-free. However, KNF recommends
periodic inspection of the pump for obvious changes in noise
or vibration.
Only have repairs to the pumps performed by qualified KNF
personnel.
Housings with electrically live components may only be
opened by specialist personnel.
Use only genuine spare parts from KNF when performing
servicing work.
2.9 Disposal
Environmental
protection
Store the pump and all accessories in accordance with the
environmental provisions. Observe national and international
regulations. This applies in particular to parts that are contam-
inated with toxic substances.
If you no longer need your packaging materials (e.g. for return
shipment or other transport of the device), dispose of them in
an environmentally friendly manner.
Old devices must not be disposed of with household waste.
Proper disposal and recycling helps to protect natural re-
sources and the environment. The end user is responsible for
disposing of old devices according to national and interna-
tional regulations. Alternatively, KNF products (old devices)
may also be returned to KNF for a fee (see chapter 11 Re-
turns [}47]).
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Technical data Diaphragm pump N838_DC
12 Translation of Original Operating and Installation Instruction, KNF
347395-347606 09/23
3 Technical data
3.1 Technical data
Pump wetted materials
Pump type Pump head Diaphragm Valves
N838AN_ Aluminum EPDM FPM
N838KN_ PPS EPDM FPM
Tab.5: Pump wetted materials
Pneumatic values
Pump type Max. permissible
operating pres-
sure [bar gauge]
Ultimate vacuum
[mbar abs.] at
rated speed
Flow rate at atm.
pressure and
rated speed [l/
min]*
N838KNDC 0.5 100 32
N838ANDC 0.5 100 32
Tab.6: Pneumatic values
Pneumatic connections
Pump type Value
N838AN_ Thread size G 1/8
N838KN_ Thread size G 1/8
Tab.7: Pneumatic connections

Diaphragm pump N838_DC Technical data
Translation of Original Operating and Installation Instruction, KNF 347395-347606
09/23
13
Electrical parameters
Parameter Value
Voltage/frequency See type plate
Maximum current draw
Power consumption of the
pump
Protection class of motor:
N828ANDC IP 50
N828KNDC IP 50
N838ANDC IP 50
N838KNDC IP 50
Maximum supply voltage fluc-
tuations
± 10%
Tab.8: Electrical parameters
Weight
Pump type Value
N838ANDC / N838KNDC 2.4 kg
Tab.9: Weight
Other parameters
Parameter Value
Permissible ambient tempera-
ture
+ 5°C to + 40°C
Permissible media tempera-
ture
+ 5°C to + 40°C
Dimensions L x H x W [mm]:
N838_NDC Approx. 150 x 123 x 82
Highest permissible relative
air humidity of the environ-
ment
80% for temperatures up to
31°C, decreasing linearly to
50% at 40°C.
Maximum installation altitude
[m above sea level]
2000
Tab.10: Other parameters
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Product description Diaphragm pump N838_DC
14 Translation of Original Operating and Installation Instruction, KNF
347395-347606 09/23
4 Product description
Design
1Outlet (pres-
sure side)
2Inlet (suction
side)
3Motor
1 2
3
Fig.1: Design N838_NDC

Diaphragm pump N838_DC Product description
Translation of Original Operating and Installation Instruction, KNF 347395-347606
09/23
15
Function of a diaphragm pump
1Outlet valve
2Inlet valve
3Transfer
chamber
4Diaphragm
5Eccentric
6Connecting
rod
21
4
3
6
5
Fig.2: Function of a diaphragm pump
Diaphragm pumps transfer, compress (depending on the ver-
sion) and evacuate gases and vapors.
The elastic diaphragm (4) is moved up and down by the ec-
centric (5) and the connecting rod (6). In the downwards
stroke, it aspirates the gas to be transferred via the inlet valve
(2). In the upwards stroke, the diaphragm presses the medium
out of the pump head via the outlet valve (1). The transfer
chamber (3) is separated from the pump drive by the di-
aphragm.
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Transport Diaphragm pump N838_DC
16 Translation of Original Operating and Installation Instruction, KNF
347395-347606 09/23
5 Transport
General
CAUTION
Personal injury and/or property dam-
age due to incorrect or improper trans-
port of the pump
In the event of incorrect or improper
transport, the pump can fall down, be
damaged or injure persons.
àUse suitable auxiliary means if nec-
essary (carrying strap, lifting gear,
etc.).
àWhere appropriate, wear suitable
personal protective equipment
(e.g., safety shoes, safety gloves).
CAUTION
Risk of injury from sharp edges on the
packaging
There is a risk of injury from cutting on
the sharp edges when grabbing cor-
ners or when opening the packaging.
àWhere appropriate, wear suitable
personal protective equipment
(e.g., safety shoes, safety
gloves).

Diaphragm pump N838_DC Transport
Translation of Original Operating and Installation Instruction, KNF 347395-347606
09/23
17
CAUTION
Personal injury and/or property dam-
age due to incorrect or improper trans-
port of the pump
If the pump is raised and/or carried on
the connection during transport, leaks
and/or damages to the pump may re-
sult.
àDo not carry the pump on the
pneumatic connection.
àTransport the pump in the original packaging to the instal-
lation location.
àKeep the original packaging of the pump (e.g. for later
storage).
àInspect the pump for transport damage after receiving it.
àDocument any transport damage that has occurred.
àRemove any transport safeguards on the pump prior to
commissioning.
Parameter
Parameter Value
Storage temperature [°C] + 5 to + 40
Transport temperature [°C] - 10 to + 60
Permissible humidity (non-
condensing) [%]
30 to 85
Tab.11: Transport parameters and storage parameters
NOTICE
Prior to commissioning, make sure that
the pump has reached the ambient
temperature (3 Technical data [}12]).
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Installation and connection Diaphragm pump N838_DC
18 Translation of Original Operating and Installation Instruction, KNF
347395-347606 09/23
6 Installation and connection
Only install the pumps in accordance with the operating pa-
rameters and conditions described in Chapter 3 Technical
data [}12].
àObserve the safety instructions (see Chapter 2 Safety
[}6]).
NOTICE
Damage due to particulate entering
your pump
àTake protective measures against
allowing particulate entering the
pump.
DANGER
Risk of dangerous gas mixtures during
pump operation
Depending on the medium being trans-
ferred, breakage of the media-contact-
ing components can result in a danger-
ous mixture if the medium mixes with
the air in the compressor housing or
the surroundings.
àBefore using a medium, check the
compatibility of the media-con-
tacting components (see 3 Tech-
nical data [}12]) with the
medium.
6.1 Installing the pump
àStore the pump at the installation site to allow it to adapt
to the ambient temperature before installation (condensa-
tion must not be allowed to form).
Mounting dimen-
sions
àFor mounting dimensions, see the following illustrations:

Diaphragm pump N838_DC Installation and connection
Translation of Original Operating and Installation Instruction, KNF 347395-347606
09/23
19
Fig.3: Mounting dimensions N838KNDC
Cooling air sup-
ply
WARNING
Danger of burning on hot surfaces
Hot surfaces could occur if the pump
overheats.
àWhen installing the pump, make
sure that sufficient cooling air in-
feed and discharge is ensured.
Proximity to hot
pump parts
àDuring installation, make sure that no combustible or ther-
mally deformable objects are positioned in proximity to hot
pump parts (head, motor).
Installation loca-
tion
àMake sure that the installation location is dry and that the
pump is protected from rain, spray water, splash water,
dripping water and other contaminants.
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Installation and connection Diaphragm pump N838_DC
20 Translation of Original Operating and Installation Instruction, KNF
347395-347606 09/23
àMake sure the installation location allows access for ser-
vicing.
àMake sure that access to moving parts is prevented.
The IP protection class of the pump motor is specified on
the type plate.
àInstall the pump at the highest point in the system to pre-
vent condensate from collecting in the pump head.
àProtect the pump from dust.
àProtect the pump from coating with greases and oils.
àProtect the pump from vibration and impact.
Installation posi-
tion
àThe pump can be operated in any installation position.
Use metal screws to fasten the pump at the indicated at-
tachment points. Observe the specifications of the se-
lected fasteners.
WARNING
Personal injury and/or property dam-
age from vibrations
Pump vibrations, in combination with
adjacent components, can result in
crushing and/or damage to these com-
ponents.
àMake sure that pump vibrations
cannot lead to dangers in combi-
nation with adjacent components.
Protection
against foreign
objects
àProtect the pump against contact and the ingress of for-
eign bodies.