KNF NPK012 Series User manual

NPK012
TRANSLATION OF ORIGINAL OPERATING AND
INSTALLATION INSTRUCTION
ENGLISCH
KNF 316780-316783 05/19 EN-US
OEM
Note!
Before operating the pump and the accessories, please read the operating and installation instructions and
pay attention to the safety precautions!
SWING PISTON
VACUUM PUMP

Contents
1 About this document ......................................................... 3
2 Use ................................................................................... 4
3 Safety................................................................................ 5
4 Technical data .................................................................. 7
5 Design and function .......................................................... 9
6 Transport ........................................................................ 11
7 Installation and connection ............................................. 12
8 Operation ........................................................................ 18
9 Cleaning.......................................................................... 22
10 Troubleshooting .............................................................. 23
11 Accessories .................................................................... 25
12 Returns ........................................................................... 26
KNF Neuberger GmbH
Alter Weg 3
79112 Freiburg
Germany
Phone [phone]
Fax. [phone]
www.knf.com

Swing Piston vacuum pump NPK012 About this document
Translation of original operating and installation instruction, Englisch, KNF 316780-316783 05/19 3
1 About this document
1.1 Using the operating and installation instructions
The operating and installation instructions are part of the pump.
àGive the operating and installation instructions 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 the operating and installation instruc-
tions.
àFor project pumps, also observe the agreed specifications.
1.2 Symbols and markings
Warning notice
WARNING
A notice that warns you of danger is located here.
Possible consequences of a failure to observe the
warning notice are specified here. The signal
word, e.g., warning, indicates the danger level.
àMeasures for avoiding the danger and its
consequences are specified here.
Danger levels
Signal word Meaning Consequences if not
observed
DANGER warns of immediate
danger
Death or serious injury
or serious damage will
result.
WARNING warns of possible dan-
ger
Death or serious injury
or serious damage are
possible.
CAUTION warns of a possibly
dangerous situation
Minor injuries or dam-
age are possible.
Tab.1
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.
This symbol indicates important information.

Use Swing Piston vacuum pump NPK012
4 Translation of original operating and installation instruction, Englisch, KNF 316780-316783 05/19
2 Use
2.1 Proper use
The pumps are intended exclusively for transferring gases and vapors.
Responsibility of the owner
Operating parameters and
conditions
Only install and operate the pumps in accordance with the operating pa-
rameters and conditions described in Chapter 4 Technical data.
Protect compressors with a pressure relief device between the pressure
side of the compressor and the first shut-off valve.
Only fully assembled pumps may be operated.
Make sure that the installation location is dry and that the pump is pro-
tected against rain, splash, gushing and drip water as well as from other
contaminants.
The tightness of the connections between the pipes of the application and
the pump (or the connection of the pump) is to be checked at regular inter-
vals. Leaky connections carry the risk of releasing dangerous gases and
vapors from the pump system.
Requirements for the transferred
medium
Before transferring a medium, check whether the medium can be trans-
ferred danger-free in the specific application.
Before using a medium, check the compatibility of the media-contacting
components (see 4 Technical data) with the medium.
Risk of dangerous gas mixtures during pump operation if the sealing lip
breaks: Depending on the medium being transferred, breakage of the seal-
ing lip can result in a dangerous mixture if the medium mixes with the air in
the compressor housing.
Only transfer gases that remain stable under the pressures and tempera-
tures that arise in the pump.
2.2 Improper use
The pumps may not be operated in explosive atmospheres.
The pumps are not suitable for transferring:
§Dusts
§Liquids
§Aerosols
§Biological and microbiological substances
§Fuel
§Explosives and flammable material
§Fibers
§Oxidants
§Food
Pumps that can produce both vacuum as well as overpressure may not be
used to simultaneously produce vacuum and operating pressure.
No operating pressure may be applied to the suction side of the pump.

Swing Piston vacuum pump NPK012 Safety
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3 Safety
Observe the safety notices in chapters 7 Installation and connection
and 8.1 Operation.
The pumps are built in accordance with the generally recognized rules of
technology and the occupational safety and accident prevention regula-
tions. Nevertheless, 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 intended use,
safely and aware 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 mains, observe the corre-
sponding safety rules.
Personnel Make sure that only trained and instructed personnel or specially trained
personnel work on the pumps. This applies, in particular, to assembly, con-
nection and servicing work.
Make sure that the personnel have read and understood the operating and
installation instructions, particularly the chapter on safety.
Working in a safety conscious
manner
Observe the regulations on accident prevention and safety during all work
on the pumps and during operation.
The pump heads heat up during operation; therefore avoid contact with
them.
Make certain that the pump is disconnected from mains and without
power.
Make sure that no dangers arise from flow when gas connections are
open, from noises or from hot, corrosive, dangerous and environmentally
hazardous gases.
Make sure that an EMC-compliant installation of the pump is ensured at all
times and that no dangerous situation can thereby arise.
Working with hazardous media When transferring hazardous media, observe the safety regulations for the
handling of these media.
Working with combustible media Note that the pumps are not designed to be explosion-proof.
Make sure that the temperature of the medium is always sufficiently below
the ignition temperature of the medium so as to prevent ignition or explo-
sion. This also applies for abnormal operating situations.
Note here that the temperature of the medium increases when the pump
compresses the medium.
Therefore, make sure that the temperature of the medium also remains
sufficiently below the ignition temperature of the medium even when it is
compressed to the maximum permissible operating pressure of the pump.
The maximum permissible operating pressure of the pump is stated in the
technical specifications (4 Technical data).
If applicable, also take into consideration external energy sources (e.g., ra-
diation sources) that could add heat to the medium.
In case of doubt, contact KNF Customer Service.
Environmental protection Store and dispose of all replacement parts in accordance with environmen-
tal regulations. Observe the respective national and international regula-
tions. This applies in particular to parts that are contaminated with toxic
substances.
EU/EC directives/standards 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

Safety Swing Piston vacuum pump NPK012
6 Translation of original operating and installation instruction, Englisch, KNF 316780-316783 05/19
been determined that the machine into which the partly completed machin-
ery is to be installed complies with the provisions of the Machinery Direc-
tive 2006/42/EC. The following fundamental requirements of Annex I of Di-
rective 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.
As these partly completed machines are built-in devices, the mains con-
nections and equipment for disconnecting and switching off the partly com-
pleted machinery as well as overcurrent and overload protection gear must
be considered when mounting.
Furthermore, protection against contact with moving and hot parts, if
present, must be provided during installation.
The pumps comply with Directive 2011/65/EC (RoHS2).
The following harmonized standards are satisfied:
§DIN EN 50581
§DIN EN 61000-6-2/3
Customer service and repairs The pumps are maintenance-free. KNF does, however, recommend peri-
odically inspecting the pumps for noticeable changes to noises and vibra-
tions.
Only have repairs to the pumps performed by the responsible KNF Cus-
tomer Service.
Housings with live components may only be opened by specialist person-
nel.

Swing Piston vacuum pump NPK012 Technical data
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4 Technical data
Technical data
Pump materials
Assembly Material
Ribbed plate, cylinder PPS
Sealing lip PTFE compound
Valve plate FPM
Retainer plate Aluminum
Screw Galvanized steel
Tab.2
Pneumatic values
Parameter Value
NPK012PR
Value
NPK012VA
Max. permissible operating pressure
[bar rel*]
-Continuous operation
-Interm. operation
2.5
5.0
1.0
-
Ultimate vacuum [mbar abs.] 220 140
Flow rate at atm. pressure [l/min]** 12.0 ± 10% 13.5 ± 10%
Tab.3 *Bar rel related to 1013 hPa
**Liters in standard state (1013 hPa, 20°C)
Pneumatic connections
Pump type Value
NPK012 Hose connection ID 6
Tab.4

Technical data Swing Piston vacuum pump NPK012
8 Translation of original operating and installation instruction, Englisch, KNF 316780-316783 05/19
Electrical data
Parameter Value
NPK012
Voltage [V] 24
Frequency [Hz] -
Power P1 [W] 43
Max. current consumption [A] 1.8
Motor protection class IP 20
Max. permissible mains voltage fluc-
tuations
See operating instructions for motor
Tab.5
The pump is equipped with an overcurrent protection. If this safety
function is actuated, the pump is switched off and must be manually
reset:
àDisconnect pump from mains.
àBefore switching back on, eliminate the cause of the error(s).
Weight
Pump type Weight [kg]
NPK012 approx. 0.6
Tab.6
Other parameters
Parameter Value
NPK012PR
Value
NPK012VA
Permissible ambient temperature
[°C]
+ 5 to + 40
Permissible media temperature [°C] + 5 to + 40
Max. surface temperature* [°C] + 150 + 120
Dimensions See Chapter 7.1 Installing the pump
Fig. 3
Highest permissible relative air hu-
midity of the environment
80% for temperatures to 31°C, de-
creasing linearly to 50% at 40°C.
Maximum installation altitude [m
above sea level]
2000
Protection class of pump IP 00
Starts against:
- Pressure [bar gauge]
- Vacuum [mbar abs.]
5.0
220
1.0
140
Tab.7 *Value measured at pump head

Swing Piston vacuum pump NPK012 Design and function
Translation of original operating and installation instruction, Englisch, KNF 316780-316783 05/19 9
5 Design and function
Design
1Pneumatic pump outlet
2Pneumatic pump inlet
3Motor
4Pump head
12
3
4
Fig.1 Design NPK012

Design and function Swing Piston vacuum pump NPK012
10 Translation of original operating and installation instruction, Englisch, KNF 316780-316783 05/19
Function of swing piston pump
1Inlet valve
2Outlet valve
3Transfer chamber
4Retainer plate
5Sealing lip
6Eccentric
7Connecting rod
8Compressor housing
Fig.2 Function principle of swing piston pump
Swing piston pumps transfer, compress and evacuate air.
The swing piston, consisting of retainer plate (4) and sealing lip (5), is moved
up and down by the eccentric (6) and the connecting rod (7). In the down-
wards stroke, the swing piston aspirates the gas to be transferred via the inlet
valve (1). In the upwards stroke, the swing piston presses the medium out of
the pump head via the outlet valve (2). The swing piston is sealed at the pump
housing by a sealing lip (5) and functions oil-free.

Swing Piston vacuum pump NPK012 Transport
Translation of original operating and installation instruction, Englisch, KNF 316780-316783 05/19 11
6 Transport
General
CAUTION
Personal injury and/or property damage due to in-
correct or improper transport of the pump
In the event of incorrect or improper transport, the
pump can fall down, be damaged or injure per-
sons.
àUse suitable auxiliary means if necessary
(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 corners or when opening
the packaging.
àWhere appropriate, wear suitable personal
protective equipment (e.g., safety shoes,
safety gloves).
àTransport the pump in the original packaging to the installation loca-
tion.
àStore the original packaging of the pump (e.g., for later storage).
àInspect the pump for transport damage after receiving it.
àDocument any transport damage in writing.
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-condens-
ing) [%]
30 to 85
Tab.8 Transport parameters
Prior to commissioning, make sure that the pump has reached the
ambient temperature (4 Technical data).

Installation and connection Swing Piston vacuum pump NPK012
12 Translation of original operating and installation instruction, Englisch, KNF 316780-316783 05/19
7 Installation and connection
The pumps are only to be installed in accordance with the operating pa-
rameters and conditions described in Chapter 4 Technical data.
àObserve safety notices (see Chapter 3 Safety).
7.1 Installing the pump
àBefore installing, store the pump at the installation location to allow it to
reach the ambient temperature.
Mounting dimensions àFor mounting dimensions, see the following figures:
Fig.3 Mounting dimensions pump series NPK012
*Maximum screw-in depth
Cooling air supply
WARNING
Danger of getting burned by hot surfaces
Hot surfaces could occur if the pump overheats.
àWhen installing the pump, make sure that
sufficient cooling air infeed and discharge is
ensured.
Immediate environment of the
hot pump parts
àDuring installation, make sure that no combustible or thermally de-
formable objects are positioned in the immediate environment of the
hot pump parts (head, motor).

Swing Piston vacuum pump NPK012 Installation and connection
Translation of original operating and installation instruction, Englisch, KNF 316780-316783 05/19 13
Installation location àMake sure that the installation location is dry and that the pump is pro-
tected against rain, splash, gushing and drip water as well as from
other contaminants.
àMake sure that the installation location is accessible for maintenance
and service.
àMake sure that the pump is securely attached to the intended fastening
holes.
àMount the pump at the highest point in the system to prevent conden-
sate from collecting in the pump head.
àProtect pump from dust.
àProtect pump from vibration and impact.
Protection against foreign
objects
àTake protective measures against touching and foreign objects which
could enter the pump.
7.2 Electrical connection
DANGER
Danger to life from electric shock
àOnly have the pump connected by an autho-
rized specialist.
àOnly have the pump connected if the power
supply is disconnected.
àWhen connecting to a power source, observe the applicable standards,
directives, regulations and technical standards.
àInstall a device for separating the pump motor from the electrical mains
in the electrical installation (in accordance with EN 60335-1).
àProtect the pump motors in accordance with EN 60204-1 (overcurrent
protection, overload protection).
àThe motors may only be operated in an SELV circuit.
The control lines of the BLDC motor are only protected to a voltage
of up to 1.5 kV (cf. DIN EN 6100-4-2).
If higher ESD requirements are needed, measures are to be pro-
vided by the owner himself.
Refer to the pump type plate for the max. current consumption.
àIt is recommended that an additional emergency-off system be in-
stalled.
àMount the pumps in such a way that it is not possible to touch the elec-
trically live parts (electrical connection).
The ground potential of the power supply, the interface(s) and the
pump housing are to be at the same potential. Compensating cur-
rents via the motor controller are to be prevented as they may result
in the destruction of the electronics. A sufficient potential equaliza-
tion in accordance with EN 60479-1 is to be dimensioned.
Fastening the connection cables àFasten the connection cables so that
– the cables do not come into contact with movable or hot parts.
– the cables cannot be worn or damaged on sharp corners or edges
– no tensile and pressure forces are exerted on the connection point
of the cables (strain relief)

Installation and connection Swing Piston vacuum pump NPK012
14 Translation of original operating and installation instruction, Englisch, KNF 316780-316783 05/19
Connecting the pump
1. Compare the data of the supply voltage with the details on the motor
type plate. See the pump type plate for the maximum current con-
sumption of the pump.
The supply voltage may deviate by maximum +10% or –10% from
the values on the type plate.
2. Establish the electrical connection to the pump.
Set the direction of rotation according to the arrow on the fan hood
(see 7.1 Installing the pump and operating instructions for the mo-
tor).
Control voltage may only be applied if the motor controller is sup-
plied with an operating voltage. The motor controller may otherwise
be damaged.
Ensure the correct polarity (see designation on motor). With brush-
less three-phase motors (indicated by a B at the end of the type
designation), incorrect polarity will result in destruction of the elec-
tronics.

Swing Piston vacuum pump NPK012 Installation and connection
Translation of original operating and installation instruction, Englisch, KNF 316780-316783 05/19 15
Connection diagram for motor controller
Motor
Rated voltage [V] 24
Voltage range [V] 9 – 26.4
Electrical connections
Leads connections
Function Wire lead color Signal name Size
+ Supply voltage Red U+AWG 26 / UL 3266
- Supply voltage (0 V) Black U- / GND AWG 26 / UL 3266
Input signal for speed control Blue UCtrl AWG 26 / UL 3266
Output signal for speed Green USpd AWG 26 / UL 3266
Input signal for remote ON/OFF White URmt AWG 26 / UL 3266
Input signal for direction of motor rotation Yellow URot AWG 26 / UL 3266
Input signal for speed control UCtrl
PWM frequency range [kHz] 20
[10 … 30]
Input level "high" [V] 5
[2.5…5.5]
Input level "low" [V] 0
[0…0.8]
Duty cycle range [%] PR VA
30… 0 50…0
Pulse duration description:
Min. → min. pump output
Max. → max. pump output
[%] PR VA
30
0
50
0
Input impedance @ 1 kHz [kΩ] ≥ 10
Output signal for speed USpd
Pulses per revolution [-] 6
Pulse duty cycle [%] 50
Output level "high" [V] 5
[2.5…6.0]
Output level "low" [V] 0
[0…0.8]
Max. current carrying capacity [mA] 2
Input impedance @ 1 kHz [kΩ] ≥ 10
Input signal for remote ON/OFF URmt
Input level "high" → Motor ON [V] 5
[2.5…5.5 or open contact]
Input level "low" → Motor OFF [V] 0
[0…0.8]
Input impedance @ 1 kHz [kΩ] ≥ 10
Input signal for direction of motor rotation URot
Standard for pump
Input level "high" → Motor CCW
[V] 5
[2.5…5.5 or open contact]
Not recommended for pump
Input level "low" → Motor CW
[V] 0
[0…0.8]
Input impedance @ 1 kHz [kΩ] ≥ 10
Tab.9 Connection diagram for motor controller NPK 012_DC-B-M

Installation and connection Swing Piston vacuum pump NPK012
16 Translation of original operating and installation instruction, Englisch, KNF 316780-316783 05/19
Fig.4 Connection diagram without external setpoint setting
Fig.5 Connection diagram with external setpoint setting
7.3 Pneumatic connection
CAUTION
Personal injury or property damage through
ejected plugs
If not removed, the plugs on the pressure side of
the pump can be ejected by the resulting operat-
ing pressure.
àRemove plugs during installation.
Connected components àOnly connect components to the pump that are designed for the pneu-
matic data and thermal requirements of the pump. (see Chapter 4
Technical data).
Pressure relief device àProtect compressors by means of a pressure relief device between the
pressure-side connections of the compressor and the first shut-off
valve.
Pump discharge àIf the pump is used as a vacuum pump, safely (with respect to medium
and noise) drain the hot pump discharge that may, under certain cir-
cumstances, occur at the pneumatic outlet of the pump.

Swing Piston vacuum pump NPK012 Installation and connection
Translation of original operating and installation instruction, Englisch, KNF 316780-316783 05/19 17
Connecting the pump
CAUTION
Risk of injury from mixing up suction and pressure
side
Mixing up the suction and pressure side can result
in breakage of connected components on the suc-
tion and pressure side.
àObserve the marking of inlet and outlet.
1. Remove protective plugs from the hose connection threads.
2. Connect suction and pressure line (for mounting dimensions, see
Chapter 4 Technical data).
3. Lay the suction and pressure line at a downward angle to prevent con-
densate from running into the pump.
Secure the pressure-side connections with a fastener (e.g., hose/
pipe clamp) to prevent the hoses from slipping down from the con-
nection.

Operation Swing Piston vacuum pump NPK012
18 Translation of original operating and installation instruction, Englisch, KNF 316780-316783 05/19
8 Operation
8.1 General
WARNING
Risk of burns from hot pump parts and/or hot
medium
Some pump parts may be hot during or after oper-
ation of the pump.
àAllow pump to cool after operation.
àTake protective measures to protect against
touching hot parts.
WARNING
Risk of crushing from moving components
Reaching into the open housing during operation
of the pump may result in crushing injuries to fin-
gers.
àMake sure that reaching into the housing is
avoided.
àCover the housing.
CAUTION
Risk of injury from bursting hoses during pressure
applications due to excessively high temperatures
When operating the pump in pressure applica-
tions, hoses that are not designed for the head
temperatures of the pump at the respective oper-
ating point could become porous and burst.
àUse temperature-resistant pressure hoses at
the pneumatic connections.
àWear protective equipment if necessary (e.g.,
safety gloves, hearing protection).
WARNING
Injury to eyes
Coming too close to the inlet/outlet of the pump
may result in injury to the eyes due to the present
vacuum/operating pressure.
àDo not look into the pump inlet/outlet during
operation.
àOnly operate the pumps in accordance with the operating parameters
and conditions described in Chapter 4 Technical data.
àEnsure the proper use of the pumps (See Chapter 2.1 Proper use).
àEliminate the possibility of improper use of the pumps (see Chapter 2.2
Improper use).
àObserve safety notices (Chapter 3 Safety).

Swing Piston vacuum pump NPK012 Operation
Translation of original operating and installation instruction, Englisch, KNF 316780-316783 05/19 19
àThe pumps are built-in devices. Before they are commissioned, it must
be ensured that the machines or systems into which the pumps are in-
stalled comply with the relevant provisions.
WARNING
Risk of bursting of pump head due to excessive
pressure increase
àDo not exceed the maximum permissible op-
erating pressure (see 4 Technical data).
àMonitor the pressure during operation.
àIf the pressure exceeds the maximum permis-
sible operating pressure of the pump: immedi-
ately switch off the pump and remedy the fault
(see Chapter 10 Troubleshooting).
àOnly throttle or regulate the air or gas quantity
on the suction line to prevent the maximum
permissible operating pressure from being ex-
ceeded.
àIf the air or gas quantity on the pressure line is
throttled or regulated, make sure that the max-
imum permissible operating pressure at the
pump is not exceeded.
àEnsure that the pump outlet is not closed or
restricted.
Excessive pressure, with all of the associated hazards, can be pre-
vented by means of a bypass line with a pressure relief valve be-
tween the pressure and suction sides of the pump. Further informa-
tion is available from the KNF technical adviser (for contact data,
see www.knf.de).
Operation with open suction-side gas connection can result in con-
taminants and objects being drawn in.
Pump standstill àWhen the pump is at a pump standstill, establish normal atmospheric
pressure in the lines.
The pump may start up against pressure and/or vacuum during
switch-on (see 4 Technical data). This also applies during operation
after a brief power failure.
àEnsure that normal atmospheric pressure is present in the lines when
switching on.
Vapors as medium The service life of the sealing lip can be extended by preventing the forma-
tion of condensate in the pump. Therefore:
àOnly perform work with saturated or nearly saturated vapors with a
warm pump.
àKNF recommends: When transferring aggressive media, flush the
pump before switching off (see Chapter 9.1 Flushing the pump) to ex-
tend the service life of the sealing lip.
Switching off/decommissioning
pump
àEstablish normal atmospheric pressure in the lines (relieve pump
pneumatically).
Recommissioning àBefore recommissioning, observe the applicable standards, guidelines,
regulations and technical standards at the electrical connection.
Inspecting the pump àInspect the pump periodically for external damage or leakage.

Operation Swing Piston vacuum pump NPK012
20 Translation of original operating and installation instruction, Englisch, KNF 316780-316783 05/19
8.2 Control functions DC-B-M
8.2.1 Speed specification
Speed without external setpoint setting
The motor operates the pump with a non-variable speed over the entire
permissible pressure range (see Fig. 4).
Speed with external setpoint setting
The motor operates the pump with a variable speed between nmin and nmax
(see Fig. 5). The speed is specified by means of the control voltage (UCtrl).
Specification of the speed is performed via the blue lead ( Connection dia-
gram for motor controller NPK 012_DC-B-M).
8.2.2 Speed output
The speed is output via the green lead ( Connection diagram for motor
controller NPK 012_DC-B-M).
The motor controller generates a speed synchronous square frequency ().
Fig.6 Speed output NPK 012_DC-B-M
8.2.3 Input signal for direction of motor rotation
The input signal for direction of motor rotation is applied via the yellow lead
( Connection diagram for motor controller NPK 012_DC-B-M).
8.2.4 Input signal for remote ON/OFF
The input signal for remote ON/OFF is applied via the white lead ( Connec-
tion diagram for motor controller NPK 012_DC-B-M).
8.3 Intermittent operation (NPK012PR)
Switch-on duration/pulsed operation
At pressures in excess of 2.5 bar, the switch-on duration must be limited.
We recommend a maximum switch-on duration of 15 min followed by a
rest time of equal length.
The switch-on duration and switch-off duration are dependent on the heat
generated in the pump head as well as its heat dissipation while at rest. If
the pump is allowed to cool further, the switch-on duration can be ex-
tended or the rest phase shortened.
The maximum permissible temperature in operation should not exceed
150°C at the pump head and 95°C at the motor housing.
See sketch for measuring point: