US20170122326A1

US20170122326A1 - Centrifugal pump assembly

Info

Publication number: US20170122326A1
Application number: US15/341,362
Authority: US
Inventors: Mathis DAHLQVIST; Christian Guldbæk SMITH; Kåre Iversen
Original assignee: Grundfos Holdings AS
Current assignee: Grundfos Holdings AS
Priority date: 2015-11-03
Filing date: 2016-11-02
Publication date: 2017-05-04
Also published as: EP3165510A1; CN107023496A

Abstract

A centrifugal pump assembly includes an electric motor (2) driving a centrifugal pump (1) and includes an electronics casing (8). In the electronics casing (8), the control electronics (10, 11) for the pump and motor are integrated. A device for detecting particles in a fluid fed via a bypass (6, 7) of a delivery conduit (3) is also in the electronics casing (8).

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority under 35 U.S.C. §119 of European Application 15 192 735.7 filed Nov. 3, 2015, the entire contents of which are incorporated herein by reference.

FIELD OF THE INVENTION

The invention relates to a centrifugal pump assembly, and activating a speed-controllable centrifugal pump assembly, in particular a pump assembly delivering drinking water, with at least one electric motor, with at least one electromotorically driven centrifugal pump and with control electronics. The invention moreover relates to a method for activating such a centrifugal pump assembly.

BACKGROUND OF THE INVENTION

Centrifugal pump assemblies are counted as belonging to the state of the art in their many different construction types. They serve for delivering fluids, and are present having a single-stage or multi-stage design, as an inline embodiment or other embodiment. A common design feature is at least one electric motor which drives at least one centrifugal pump, as well as control electronics. Thereby, with modern centrifugal pump assemblies, the control electronics typically comprise an electronic speed controller, for example a frequency converter, with which the motor speed and thus the speed of the pump can be varied within large limits. Centrifugal pump assemblies in the context of the present invention are also to be understood as those with which two or more electric motors each with centrifugal pumps driven by these are provided, e.g. double pumps which have a common electronic control and spatial arrangement.
Pump assemblies of this type are designed for delivering fluids. It is particularly with the delivery of drinking water, but also with the delivery of other fluids, that it can become necessary to detect the quality of the fluid and to monitor it. Thus, for drinking water quality, it is essential to know which type and which quantity of bacteria or other particles are present. However, in the field of processing technology too, it can also be necessary to monitor the fluid fed to a process, and this being the case with regard to its qualitative/quantitative particle contamination. Such monitoring methods, in particularly also devices, with which this is possible in a largely automated manner, in the meantime are now counted as belonging to the state of the art. It is known to irradiate a fluid sample in an optical analysis device and to determine the type and the number of particles located in the sample, from EP 2 469 264 A1.
The device according to EP 2 469 264 A1 however can only carry out this evaluation with a quasi still fluid, which is why the device appears to be rather unsuitable for integration into a conduit system with a throughflow. A further problem is the arrangement of such a device in a facility, since the device comprises highly sensitive optical measuring devices.

SUMMARY OF THE INVENTION

According to the invention, one envisages designing a centrifugal pump assembly of the known type, with a device for detecting particles in fluids. Thereby and according to the invention, at least means of feeding delivery fluid to the device are provided in the centrifugal pump assembly, in order to be able branch at least a part-flow of the delivery fluid to the device and to ensure that a sample of the delivery fluid is given to the device in a quasi continuous manner or when required.
A basic concept of the present invention, is to integrate a device for detecting particles in fluid, into a centrifugal pump assembly, and thereby, even if the device does not operate in a continuous manner, to create certain synergies, in particular in a further development, to design the centrifugal pump assembly for carrying out a method according to the invention which will yet be explained further below.
The centrifugal pump assembly according to the invention and which in particular is a drinking water delivery pump assembly, comprises at least one electric motor and at least one electromotorically driven centrifugal pump, as well as control electronics. According to the invention, the assembly is provided with a device for detecting particles in fluid and moreover comprise at least means for feeding delivery fluid to this device. The centrifugal pump assembly according to the invention is thus not only designed for delivering fluid, but also for examining parts of this fluid in a quantitative and/or qualitative manner, with regard to particles located in the fluid. Thereby, particles in the context of the present invention are typically bacteria, but also suspended matter or sediment matter of a similar size.
The centrifugal pump assembly typically comprises an electric motor and a single-stage or multi-stage centrifugal pump which is driven by this. It can however also be configured as a double pump. An assembly in the context of the present invention can also be the arrangement and connection of several centrifugal pumps which are driven by an electric motor in each case and which comprise common control electronics or at least a common control electronics part assigned to such a device, for example an arrangement as is offered by the Applicant under the name Grundfos Multi Hydro.
The inventive design of the centrifugal pump assembly with such a device has the advantage that it is ensured that the device is arranged at a central location, specifically where the fluid is delivered, and that moreover the control electronics for the device on the one hand and for the control of the electric motor which is to say of the centrifugal pumps connected thereto, on the other hand, at least spatially are largely brought together. The centrifugal pump assembly is a construction unit, essentially consisting of the centrifugal pump, control, electric motor and device.
Synergistic effects such as the utilization of a common mains supply connection, the common utilization of mains parts, the common utilization of microprocessors, memories and similar digital components, as well as of communication components with LAN connection, WLAN connection, Bluetooth connection, infrared connection and likewise, result on account of this. Finally, the centrifugal pump assembly always forms a type of foundation in a facility, be it by way of calm location being formed by the mass concentration in the pipe system or be it by way of the centrifugal pump assembly itself being supported by a foundation. This is particularly advantageous with regard to the arrangement of the device, since it is hereby the case of a sensitive optical analysis system. Finally, the feed or supply of the delivery fluid to the device on the pump assembly can be utilization in a particularly simple and inexpensive manner by way of either suitable channels being provided in pump components, or a connection being effected via conduits. In both cases, the constructional effort is minimal and can be effected on the part of factory, and thus no pipe working is necessary on location.
The patent application filed by the Applicant at the European Patent Office with the application Ser. No. 14/186,884.4 and describing in detail such a device with an exchangeable sample carrier, is additionally referred to.
Advantageous designs of the invention are specified in the de-pendent claims, the subsequent description and the drawings.
It is particularly advantageous if the device is hydraulically integrated into a bypass of the delivery path of the pump or pumps, since then, as the case may be, one can make do without a separate pump for the delivery of the fluid from and to the device, at least when the device with its feed conduit is connected to the pump assembly at the delivery side, and with a return conduit which is present at the case may be, to the pump assembly at the suction side, thus counter to the delivery path of the pump.
Alternatively or additionally, the device at the exit side can advantageously comprise a conduit for the connection to a discharge, in particular to a waste water conduit or a capture container, if the fluid examined in the device is to be prevented from getting back into the delivery path. It is also conceivable to feed the examined fluid to suitable sample containers and to archive it.
According to a further development, one envisages providing an electrically controllable shut-off valve, advantageously at the entry and exit side of the device, in order to be able to control the feed of fluid to the device and the discharge of fluid away from the device. With this, the device can be charged automatically or on receipt of a corresponding control command in the control electronics. It is particularly advantageous if an electronics casing accommodates at least parts of the device or the device itself, in the case that the centrifugal pump assembly, as is often the case, is configured as a construction unit essentially consisting of a centrifugal pump, an electric motor driving this pump and this electronics casing (housing) which as a rule is fastened to and arranged on the motor casing. This is also particularly advantageous due to the fact that the mechanical and hydraulic subassemblies which is to say componentries, specifically the electric motor and the pump, can remain largely unmodified, thus here one can apply subassemblies which can also be applied with other centrifugal pump assemblies, and it is only the electronics casing which needs to be adapted accordingly. The latter can be configured in a largely free manner, and this being with regard to the inner construction as well as the outer spatial extension.
The centrifugal pump assembly according to the invention is not only used for examining a part of the delivery fluid, but in a further development of the invention is also advantageously used for treating the delivery fluid, in particular if, on examination, it is ascertained in the device that such further action is needed, for example if the bacteria contamination of the delivery fluid, in particular of the drinking water is too high, or a certain bacteria type in too high a concentration is ascertained. According to an advantageous design of the invention, a speed-controllable centrifugal pump assembly with regard to the speed is then to be activated in a manner depending on the type and/or number of the detected particles. Thus, speed interventions can be envisaged in the control electronics of the centrifugal pump assembly, and these interventions for example activate the pump with an increased speed when a defined number of particles per unit of volume has been exceeded and registered in the device, or if certain bacteria are detected or detected in an unallowably high quantity. Thereby, according to the invention, one can envisage the pump being activated with a speed or speed sequence which in particularly causes cavitation in the suction region of the pump, in order to kill at least a share of this bacteria or for example to disintegrate large particles into smaller ones. A delivery fluid treatment appliance, for example by way of UV radiation, ultrasound radiation, X-ray radiation or likewise can be alternatively or additionally be provided in the pump assembly, wherein this delivery fluid treatment appliance can be activated on exceeding a defined limit valve within the device and deactivated again on falling short of this.
According to a further development of the invention, the control electronics of the centrifugal pump assembly according to the invention are configured such that they operate the drive of the pump in another manner, in particularly activate it into activation, as soon as a number of particles per volume unit of delivery fluid and/or a type of particle is detected by way of the device, said number and/or type reaching a previously set quantitative and/or qualitative limit value. A fluid treatment appliance which is integrated in the pump assembly or is arranged directly upstream or downstream of the pump, in the flow path, can be activated instead of or additionally to the recontrol of the pump assembly, which is to say the operation of this pump assembly in another manner, and this in particular being the case with the delivery of drinking water but also on delivering fluids in industrial processes.
It is particularly advantageous if the control electronics are de-signed such that they feed a fluid quantity from the delivery flow to the device in predefinable temporal intervals by way of opening valve actuation, and activate the device for detecting particles. A quasi continuous monitoring of the delivery fluid is possible with such a device. The detection of particles by the device, with regard to time can be effected simultaneously with the pump activation of the centrifugal pump. In a variant of the invention, the pump is automatically stopped whilst the device detects particles, or the speed of the pump is automatically closed-loop controlled to a speed which produces no or little vibration. The speed can also be kept constant during the detection. The fluid is kept calm during the detection by way of this.
It is particularly when examining drinking water, that it is practically impossible to prevent accumulations (deposits) from forming over the course of time, such as bio-film, lime-scale or likewise. According to the invention, one envisages equipping the device with a sample carrier, which although being able to be subjected to throughflow, the actual examination however is effected in it given a still/calm fluid, thus is effected in a quasi stationary manner, in order here to ensure that the qualitative/quantitative examinations of the device can take place in a reliable manner and with the necessary precision. According to the invention, this sample carrier is advantageously arranged on the device in an exchangeable manner, and specifically such that it is accessible from a casing side of the centrifugal pump assembly, in particular of the electronics casing—if the device is integrated there. The sample carrier is advantageously arranged such that it is arranged at an easily accessible location of the centrifugal pump assembly and can be rapidly and simply exchanged.
Even if the centrifugal pump assembly, in particular the pump with the electric motor, forms a certain calm foundation for the device, according to a further development of the invention, one envisages at least the mechanical/optical part of the device being arranged within the casing, in particular within the electronics casing, in an oscillation-damped manner, in order to prevent the oscillations/vibrations which are produced by the electric motor, but also possibly introduced into the assembly via the pipe conduit system, from negatively affecting the sensitive optical/mechanical components, leading to a worsening of the measurement.
It is particularly if the centrifugal pump is integrated into a high-pressure conduit, or, as can particularly be the case with multi-stage pumps, the pump delivers at a high pressure, that it is advantageous to provide means for pressure reduction at the entry side of the device, so that the device, in particular the sample carrier, is not subjected to the high system pressure.
According to an advantageous further development of the invention, these means for pressure reduction in the entry conduit of the device can however be deactivated, either by way of a corresponding activation or by way of the provision of a bypass. This deactivation is advantageously utilized to flush the device at increased pressure, in order to remove the already mentioned deposits/sediments.
Although the device can be subjected to the pressure of the delivery fluid, as initially mentioned, in particular if it is connected to the delivery side of the pump, this however always assumes that the pump delivers, and specifically at the necessary pressure. A design, with which a separate pump is provided for feeding and/or discharging delivery fluid and with which this pump is preferably arranged in the electronics casing, is more independent inasmuch as this is concerned. Hereby, it can likewise be the case of a centrifugal pump, however it is advantageously the case of a displacement pump, and for example of a membrane pump or of an impeller pump. It is always ensured that a suitable quantity of delivery fluid is fed to the device or led away out of this, on account of such a pump, independently of the system condition of the delivery pump.
Furthermore, it is advantageous if the device comprises an irradiation appliance for the fluid which is located in the device or is led out of the device. Such an irradiation appliance for example can be a UV irradiation appliance which ensures that the fluid which is led out of the device is not contaminated with germs. Such an irradiation appliance is also advantageously arranged within the electronics casing. The electronics casing at the same time thereby forms a protective casing which prevents radiation of the irradiation appliance from getting to the outside.
The control electronics which are at least partly arranged within the electronics casing advantageously comprise control and evaluation electronics of the device, as well as control electronics of the pump, in particular the speed controller electronics activating the electric motor driving the centrifugal pump.
Thereby, the control electronics advantageously comprise means for storing data of the evaluation electronics as well as means for wired and/or wireless transmission of the data of the evaluation electronics and/or of stored data. Thereby, the communication means for transmitting data can advantageously serve for transmitting the data of the device as well as for transmitting the data of the pump control. In particular, the digital componentries or units of the control electronics such as the processor, the working memory and the ROM can advantageously be used for the data of the pump control as well as for data of the device. With the application of frequency converter technology which is common today, parts of the existing electronics for example can also be used for the control and evaluation of the device on account of this. In particular, the complete sequential control for the device can be assumed by these.
The invention is hereinafter explained in more detail by way of embodiment examples. The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 is a block diagram relating to a centrifugal pump assembly according to the invention, with a device for detecting particles in fluids;

FIG. 2 is a perspective view of a multi-stage inline centrifugal pump with an electric motor, electronics casing and a device which is integrated into this, in a greatly simplified and perspective lateral view;

FIG. 3 is a perspective view of a pump assembly according to FIG. 2, in a perspective view from another side;

FIG. 4 is a side a view of the pump assembly according to FIG. 2, in a lateral view;

FIG. 5 is another side a view of the pump assembly according to FIG. 2, in a lateral view which is rotated by 90 with respect to FIG. 4;

FIG. 6 is a greatly simplified perspective view showing a circulation pump assembly with a device for detecting particles in fluid;

FIG. 7 is a greatly simplified perspective view showing the centrifugal pump assembly according to FIG. 6, in a different perspective representation;

FIG. 8 is a front view of the centrifugal pump assembly according to FIG. 6;

FIG. 9 is a side view of the centrifugal pump assembly according to FIG. 6; and

FIG. 10 is a side view onto the centrifugal pump assembly according to FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the drawings, the basic construction of a centrifugal pump assembly according to the invention is represented by way of FIG. 1. The centrifugal pump assembly comprises a centrifugal pump 1 which is driven by an electric motor 2. The centrifugal pump 1 delivers through a main delivery conduit 3, whose entry in FIG. 1 is indicated at 4 and whose exit at 5. The main delivery conduit 3 at the entry side leads to the suction side of the pump 1, whose delivery side is connected to the exit 5 via the conduit.
A bypass conduit 6, 7 which divided up into a delivery-side part 6 and a suction-side part of the bypass 7, is provided parallel to the centrifugal pump 1. This bypass conduit 6, 7 leads into an electronics casing 8 which is arranged and fastened on the electric motor 2 and forms a type of terminal box, into which on the one hand the windings of the motor are led out and contacted and into which on the other hand an electrical mains supply 9 is led. A device for detecting particles in fluid and whose construction for the most part is described in the European patent application 14186884.4 of the Applicant, which is explicitly referred to here, is integrated within this electronics casing 8. The mechanical as well as the electronic part of the above-mentioned device, as well as the control and regulation electronics of the motor 2 or of the pump 1 connected thereto, are therefore arranged in the electronics casing 8.
The motor control is characterized at 10 in FIG. 1, and it comprises a frequency converter whose output directly affects the windings of the electric motor 2. A pump control 10 communicating with sensors within the pump 1 via an input/output interface 12 is serially connected before the motor control 10.
A display 13, an operating surface 14, as well as a communication interface 15 which are connected to the pump control 11 as well as to control electronics 16 forming part of the device for detecting particles, are moreover provided within the electronics casing 8. With regard to the display 13, it is the case of an LCD display, but here, it can basically also be the case of any other suitable signal or display device. The operating surface 14 is configured as a membrane keyboard, but here too, any other suitable signal input source can be applied. A LAN connection as well as a WLAN transmitter-receiver is provided as a communication interface 15. Basically, any other suitable communication interface can be applied here as well.
The device for detecting particles in fluid is fed via the part of the bypass conduit 6 which is branched from the main delivery conduit 3 at the delivery side. A controllable pressure reducer 17 is firstly provided within the device, downstream of which pressure reducer a delivery pump 18 is connected, wherein this delivery pump is connected to the actual analysis device via a controllable shut-of valve 19. The analysis device consists essentially of an illumination source 20, of a receiving device 21 for a sample carrier and of an optical sensor 22 in the form of a sensor matrix whose data is evaluated in the control electronics 16, stored and transmitted further. The receiving device 21 for the sample carrier, at the exit side is connected via an electrically controllable shut-off valve 21 to a UV treatment appliance 24, whose exit is connected to the suction-side part 7 of the bypass conduit running out at the suction side of the pump, at the entry 4, into the main delivery conduit 3. One can make do without the delivery pump 18 in systems having a relatively high pressure.
A branching 25, via which the fluid coming from the analysis device 20, 21, and 22 can be lead to a collection container 26 in the case that this fluid is not to be fed to the main delivery conduit 3, is provided within this conduit 7, wherein this collection container 26 for example also represents a discharge conduit, a capture container or an archiving system, in which the fluid coming from the analysis device 20, 21 and 22 can be captured and/or archived. In a variant of the invention, no fluid in the bypass conduit is branched off or not only fluid in the bypass conduit but also the fluid in the main delivery conduit 3 which is actually to be delivered. In the case of a bacteria alarm, the control electronics can switch a switch-over valve in the main delivery conduit (the switch-over valve is not represented in the drawing) such that the fluid which is infected with bacteria can be diverted into another conduit. This switch-over valve can be autonomously incorporated in the main conduit, or be a part of the centrifugal pump assembly, e.g. be installed in the pump casing.
The device for detecting particles in fluid, as is represented by way of FIG. 1, comprises a controllable pressure reducer 17, a delivery pump 18, an analysis device 20-22 which is integrated into the conduit 6, 7 via two shut-off valves 19 and 23, and a UV treatment appliance 24 which is connected downstream. The complete sequential control, evaluation, storage and further transfer of data are effected in the control electronics 16. The operation of the device, with the exception of the exchange of the sample carrier located in the receiving device 21 is effected via the operating surface 14, via which the operation of the pump control is also effected. The display of the device is effected via the display 13, via which the display of the pump control is also effected. The control electronics 16 as well as the pump control 11 moreover use the same communication interfaces 15. The common use of the digital components of the control electronics 16 and of the pump control 11, specifically of the processor, the working memory and ROM is not represented in detail in FIG. 1. The components which are provided for the detection of particles in the fluid and which are provided in the electronics casing 8 are characterized at 8 a and those provided for the pump/motor control at 8 b. Hereby, the overlapping region concerning the display 13, the operating surface 14 and the communication interfaces 15, which are assigned to the device as well as to the motor/ pump control 10, 11 are clearly visible here.
The fluid gets into the device for detecting particles in fluid, via the bypass conduit 6, firstly into the pressure reducer 17 which can be controlled by way of the control electronics 16 and which ensures that the fluid does not exceed a predefined pressure. The fluid to be analyzed gets into the sample carrier located in the receiving device 21, via the delivery pump 18 when the valves 19 and 23 are open. The valves 19 and 23 are subsequently closed, whereupon the analysis of the fluid sample located in the analysis device 20-22 takes place, the sequential control and evaluation of this analysis being effected in the control electronics 16. The fluid located in the analysis device can be led through the UV treatment appliance 24 by way of opening the valves 19 and 23, after the analysis has been effected, and the fluid sample which is examined in the analysis device 20-22 is subjected to a UV treatment as the case may be, in order to kill bacteria located therein. The UV treatment is usefully only effected in the case of an increased or particular bacteria contamination of the fluid sample. The fluid which is purified inasmuch as this is concerned can then be led via the part 7 of the bypass conduit again at the entry side, to the delivery flow of the main delivery conduit 3, if a leading of fluid in a closed circuit is desired. It is also possible to attach the UV irradiation appliance 24 in the analysis device 20-22 and to irradiate the fluid in a direct manner.
A sample carrier which is located in the receiving device 21, for the purpose of purification, can also be purified by way of the valves 19 and 23 being opened and the pressure reducer 17 being controlled in a functionless manner. The fluid then flows via the bypass conduit 6, 7 at the delivery pressure of the pump 1 in the return through the device, wherein the pump 18 is switched so that there is no current and is subjected to throughflow. In the case that it is not a centrifugal pump but a displacement pump which is applied as a pump 18, then a bypass conduit which can be released for the purpose of the flushing procedure is to be provided at this location.
If for example an increased or certain bacterial contamination is ascertained in the fluid, one then further envisages the pump control 11 receiving a signal on account of the control electronics 16, said signal initiating the pump control into activating the speed of the electric motor 2 such that the pump 1 cavitates in its suction region, which is to say produces cavitation in a targeted manner and, by way of this, affects the delivery fluid such that bacteria is killed. Thereby, not only the sample fluid which is led back into the main delivery conduit 3, but also the complete main delivery flow is treated by way of this cavitation effect of the pump.
It is shown by way of example and by way of FIG. 2-5, as to how the coupling of componentries and which is schematically represented by way of FIG. 1 can be integrated into a pump assembly, as is known for example with the CRE construction series of the Applicant (controlled vertical multi-stage centrifugal pumps). The constructional changes are comparatively small compared to a standard pump assembly. Here, on the part of the pump, only the conduits 6 and 7 for the bypass conduit need to be led out, which does not require any large constructional modification since, as FIG. 2-5 make clear, the suction-side part 7 is led out close to the connection branch, and the delivery-side part 6 is led out of the pump head. The electronics casing 8 with regard to its constructional size is significantly enlarged, since it needs to accommodate the device for detecting particles, which is to say the componentries or subassemblies 17-24. The receiving device 21 for the sample carrier exchangeable from the front can be clearly recognized in the representations according to FIGS. 2-5, and this receiving device is accessible from the front on the electronics casing.
As to how an electronics casing 8 of a common circulation pump can be configured, in order to also be able to accommodate the subassemblies 17-24, is represented by way of example by way of FIGS. 6-10. The conduits 6 and 7 with this single-stage pump according to FIG. 6-10 are led outside the pump casing. The conduits 6 and 7 however can also be formed within the pump casing by way of channels which are led into the electronic casing via the base of this.
It is to be noted that the reference numerals used for FIG. 4-10 concern components having the same function, despite their construction design not corresponding to one another.
While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

Claims

What is claimed is:

1. A centrifugal pump assembly delivering a delivery fluid and with which the delivery fluid is monitored quantitatively and/or qualitatively, the pump assembly comprising:

at least one electric motor;

at least one electromotorically driven centrifugal pump;

control electronics;

a particle detection device for detecting particles in delivery fluid; and

a fluid feed for feeding delivery fluid to the particle detection device.

2. A centrifugal pump assembly according to claim 1, further comprising a delivery path of the pump wherein:

a fluid bypass is connected to the delivery path of the pump;

the fluid feed is a part of the bypass; and

the particle detection device is integrated into the fluid bypass.

3. A centrifugal pump assembly according to claim 2, wherein the particle detection device at an exit side comprises a conduit for a connection onto a discharge comprising a waste water conduit, or a capture container.

4. A centrifugal pump assembly according claim 3, further comprising an electrically controllable shut-off valve at the entry side and/or at the exit side of the particle detection device.

5. A centrifugal pump assembly according claim 1, wherein the control electronics are arranged in an electronics casing which accommodates at least parts of the particle detection device and which is fastened on the motor casing and/or pump casing.

6. A centrifugal pump assembly according claim 1, wherein the control electronics are configured to operate the drive of the pump to activate the pump into cavitation, so soon as a number of particles per volume unit of the delivery fluid and/or a type of particles is detected by way of the particle detection device, said number reaching a previously defined value and/or said type corresponding to a previously defined type.

7. A centrifugal pump assembly according claim 1, wherein the control electronics are configured to feed a fluid quantity from a delivery flow to the particle detection device in predefined temporal intervals by way of opening a valve actuation, and activate the particle detection device for detecting particles.

8. A centrifugal pump assembly according claim 1, wherein the particle detection device comprises a sample carrier which is accessible from a casing side and which is arranged in an exchangeable manner.

9. A centrifugal pump assembly according claim 1, wherein at least a mechanical/optical part of the particle detection device is arranged within a casing in an oscillation-damped manner.

10. A centrifugal pump assembly according claim 1, wherein a pressure reduction device is provided at the entry side of the particle detection device.

11. A centrifugal pump assembly according to claim 10, wherein the pressure reduction device is deactivated for the purpose of flushing.

12. A centrifugal pump assembly according claim 1, wherein the particle detection device comprises a pump arranged in an electronics casing and is feeds and/or discharges the delivery fluid.

13. A centrifugal pump assembly according claim 1, wherein the particle detection device comprises an irradiation appliance for the fluid which irradiation appliance is located in the particle detection device or is led out of the particle detection device, said irradiation appliance being arranged in the electronics casing.

14. A centrifugal pump assembly according claim 1, wherein the control electronics comprises control and evaluation electronics of the particle detection device as well as control electronics of the pump including speed controller electronics.

15. A centrifugal pump assembly according claim 14, wherein the control electronics further comprise a data storing device of the evaluation electronics as well as a transmission device for a wired and/or wireless transmission of data of the evaluation electronics and/or of stored data.

16. A method for activating a speed-controllable centrifugal pump assembly, for delivering drinking water, with which the delivery fluid is monitored quantitatively and/or qualitatively, with regard to the particles including bacteria, which are located therein, the method comprising:

providing the centrifugal pump assembly, wherein the centrifugal pump assembly comprises at least one electric motor, at least one electromotorically driven centrifugal pump, control electronics, a particle detection device for detecting particles in delivery fluid and a fluid feed for feeding delivery fluid to the particle detection device; and

effecting activation of the speed in dependence on a type and/or number of the detected particles.

17. A method according to claim 16, wherein the pump is temporarily activated with an increased speed on reaching a number of particles per volume unit of the delivery fluid and/or on detecting a predefined type of particles.

18. A method according to claim 16, wherein the pump is activated to produce cavitation on reaching a number of particles per volume unit of the delivery fluid and/or on detecting a predefined type of particles.