CN203643333U - Turbidity meter - Google Patents
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- CN203643333U CN203643333U CN201320733447.0U CN201320733447U CN203643333U CN 203643333 U CN203643333 U CN 203643333U CN 201320733447 U CN201320733447 U CN 201320733447U CN 203643333 U CN203643333 U CN 203643333U
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Abstract
The utility model discloses a turbidity meter. The turbidity meter comprises a light source module, a detecting-receiving module and a calculating module, wherein the light source module is used for periodically emitting two incident lights of different frequencies into a to-be-measured water sample; the detecting-receiving module is used for receiving scattered lights at positions forming an angle of 90 degrees and an angle of 130 to 140 degrees with the incident lights, generating voltage sampling signals and sending the voltage sampling signals to the calculating module; the calculating module is used for calculating the turbidity of the to-be-measured water sample according to the voltage sampling signals. According to the turbidity meter, by emitting the two lights of different frequencies which cannot be interfered with each other, the interferences caused by stray lights and background colors in water to measurement are avoided effectively; the scattered lights are received at the two positions forming the angle of 90 degrees and the angle of 130 to 140 degrees with the incident lights, so that the monitoring on large particulate matters in the water sample is enhanced, and the measuring accuracy is improved.
Description
Technical Field
The utility model relates to a water quality measurement field, in particular to turbidity meter.
Background
The turbidity of water is an optical property of sample water, and means that light scattering caused by suspended solid particles and impurities in the sample water causes the transparency of the sample water to be reduced. According to the international standard for turbidity measurement ISO7027 and the U.S. environmental standard EPA180.1, most turbidity meters currently produced on the market use scattered light whose direction of measurement is at an angle of 90 ° to the direction of the incident light to determine the turbidity value and the light source uses a direct current emission method. On one hand, the method is easily interfered by stray light and background color in water, and on the other hand, the linearity is not good when high-turbidity sample water is measured. And the light source is used for a long time in a direct current emission mode, so that the device is aged quickly, the light source is easy to attenuate, and the light source needs to be calibrated frequently. The above problems all affect the accuracy of the turbidity measurement of water.
Disclosure of Invention
An object of the utility model is to provide a turbidity meter to improve measuring accuracy.
Based on the above purpose, the embodiment of the utility model provides a turbidity meter, which comprises a light source module, a detection receiving module and a calculation module;
the light source module is used for periodically emitting two incident lights with different frequencies to the sample water to be measured;
the detection receiving module is used for receiving scattered light at positions which form 90 degrees and 130-140 degrees with incident light, generating a voltage sampling signal and sending the voltage sampling signal to the calculation module;
the calculation module is used for calculating the turbidity of the sample water to be measured according to the voltage sampling signal.
Preferably, the light source module comprises two light source sub-modules; the frequency and the incident position of incident light emitted by the two light source sub-modules are different;
the detection receiving module comprises four detection receiving sub-modules; the two detection receiving sub-modules respectively receive scattered light at positions which form 90 degrees and 130-140 degrees with incident light of one frequency; the other two detection receiving sub-modules respectively receive scattered light at positions which form 90 degrees and 130 degrees to 140 degrees with the incident light of the other frequency;
wherein,
each light source submodule consists of an emission photodiode, a parallel light lens group and a photodiode driving circuit;
the photodiode driving circuit is used for sending a driving signal to the emitting photodiode, and the driving signal comprises a specified frequency;
the emission photodiode is used for emitting incident light with specified frequency to sample water to be measured according to the driving signal;
the parallel light lens group is used for focusing incident light emitted by the emitting photodiode;
and/or;
each detection receiving submodule consists of a receiving photodiode, a lens group, a current/voltage conversion circuit, a band-pass filtering amplification circuit, an effective value conversion circuit and an A/D converter;
the lens group is used for focusing the scattered light signal on the receiving photodiode;
the receiving photodiode is used for converting the scattered light signals into corresponding current signals;
the current/voltage conversion circuit is used for converting the current signal into a corresponding initial voltage signal;
the band-pass filtering amplifying circuit is used for amplifying the initial voltage signal;
the effective value conversion circuit is used for converting the amplified voltage signal to generate an effective voltage signal;
the A/D converter is used for converting the effective voltage signal into a corresponding mathematical signal for sampling and generating a voltage sampling signal.
Preferably, the two light source sub-modules periodically alternate to emit incident light or the two light source sub-modules periodically emit incident light simultaneously.
Preferably, the turbidity meter further comprises a control module;
the control module is used for sending instructions to the photodiode driving circuit; the instructions include specifying a frequency.
Preferably, the control module and the calculation module are integrated on the ARM single chip microcomputer.
Preferably, the turbidity meter further comprises a flow-through module and/or a washing module;
the circulation module is used for providing sample water to be measured in real time and enabling the sample water to be measured to be in a circulation state;
the cleaning module is used for cleaning the light source module and the detection receiving module.
Preferably, the reception performance of a receiving photodiode matches the emission performance of a corresponding emitting photodiode.
Preferably, the receiving photodiode is a P-type photodiode.
Preferably, the two different frequencies are different from the frequency of natural light.
Preferably, the detection receiving module is configured to receive the scattered light at 90 ° and 135 ° to the incident light.
The utility model has the advantages that:
the utility model discloses a light of two kinds of mutual noninterference frequency of transmission can effectually avoid the interference of aquatic stray light and background colour, is 90 and two positions receipt scattered light 130 ~ 140 with the incident light moreover, has increaseed the monitoring to large granule material in the sample water. Furthermore, incident light is emitted by the two light source sub-modules alternately, so that the problem of device aging caused by using one light source all the time is solved. And the utility model discloses carry out filtering process to the data of sampling through digital filtering at the in-process of calculating turbidity value, avoided the influence that the bubble interference caused, improved measuring accuracy.
Drawings
FIG. 1 is a structural view of a turbidimeter according to a first embodiment;
FIG. 2 is a schematic of the measurement of sample water turbidity using two emitting photodiodes and 4 receiving photodiodes.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
The embodiment of the utility model provides a turbidity meter is provided, see fig. 1, this turbidity meter includes:
a light source module 11, a detection receiving module 12 and a calculation module 13.
The light source module 11 is used for periodically emitting two incident lights with different frequencies to the sample water to be measured. For avoiding receiving the influence of natural light, the utility model discloses in the frequency of these two kinds of incident lights all is different from the frequency of natural light.
The detection receiving module 12 is used for receiving the scattered light at positions 90 ° and 130 ° to 140 ° from the incident light, generating a voltage sampling signal and sending the voltage sampling signal to the calculating module 13.
The calculating module 13 is used for calculating the turbidity of the sample water to be measured according to the voltage sampling signal received from the detecting and receiving module 12.
In order to ensure the reliability of the sampling data, when calculating the turbidity of the sample water to be measured, the calculating module 13 first performs digital filtering on the voltage sampling signals corresponding to the received scattered light of two frequencies. Through contrast and smoothing processing, the useful signal strength is improved, and various interferences are eliminated or reduced.
Digital filtering has the following advantages over traditional hardware filtering: (1) the hardware of the system is simplified by adding a section of digital filtering before the program enters a data processing and control algorithm without adding any hardware. (2) Digital filtering can be shared by multiple channels, thus reducing cost. (3) The filter characteristics can be conveniently changed by only appropriately changing the parameters of the filter program, and the use is flexible and convenient.
The specific filtering process will be described in detail in the method embodiment.
Compared with the prior art, the utility model discloses in increased and be 130 ~ 140 degrees angle receipt scattered light with the incident light. This is because the influence of large particulate matter on incident light can be monitored to a greater extent at an angle of 130 ° to 140 ° than at other angles, and the turbidity of the sample water to be measured can be calculated more accurately. Preferably, the optimum angle is 135 ° to the incident light.
In a specific embodiment of the utility model, the light source module includes two light source submodule pieces, emits the incident light to the appearance water that awaits measuring respectively in the position of difference, and the frequency of the incident light of two light source submodule piece emissions is different. Correspondingly, the detection receiving module comprises four detection receiving sub-modules; the two detection receiving sub-modules respectively receive scattered light at positions which form 90 degrees and 130-140 degrees with incident light of one frequency; the other two detection receiving sub-modules respectively receive scattered light at positions of 90 degrees and 130 degrees to 140 degrees with incident light of another frequency.
The light source sub-module and the detection receiving sub-module have various specific structures, and a specific structure of the light source sub-module and the detection receiving sub-module is described in detail below.
Each light source submodule consists of an emitting photodiode of an LED, a parallel light lens group and a photodiode driving circuit.
The photodiode driving circuit is used for sending a driving signal to the emitting photodiode, and the driving signal contains information of a specified frequency. The photodiode driving circuit can be specifically composed of a signal generator and LED constant current driving.
And the emitting photodiode is used for emitting the incident light with the specified frequency to the sample water to be measured according to the received driving signal. Of course, the specified frequencies in the drive signals sent by the photodiode drive circuits in the two light source sub-modules are different.
The stability of the incident light has a significant impact on the turbidity measurement and a good quality emitting photodiode must be selected. According to international standard ISO7027, the light-emitting peak value of the emitting photodiode is generally selected to be about 860nm, and the emitting photodiode has high directivity, the half-value angle is selected to be 5-20 degrees, and the half-width of the spectrum is as small as possible, so that the unicity of the light-emitting wavelength is ensured.
The parallel light lens group is used for focusing incident light emitted by the emitting photodiode, so that the focused incident light is incident into the sample water to be measured.
Each detection receiving submodule consists of a receiving photodiode, a lens group, a current/voltage conversion circuit, a band-pass filtering amplification circuit, an effective value conversion circuit and an A/D converter.
The lens group is used for focusing the scattered light signal on the receiving photodiode.
The receiving photodiode is used for converting the scattered light signals into corresponding current signals.
The utility model discloses in, receiving photodiode can select for use PIN type photodiode, and its I layer is thicker, works again in reverse inclined to one side, makes junction region exhaust layer thickness increase, has improved absorption and photoelectric conversion region to the light, makes quantum efficiency improve. On the other hand, the sensitivity to long wave is increased, and the response wavelength range of the sensor can be from 0.4 to 1.1 mu m. In addition, since the I layer is thick, it can withstand a high reverse bias voltage while operating under reverse bias, which widens the linear output range. And the PIN type photodiode is small in size. Generally speaking, the PIN photodiode has the characteristics of high response speed, high sensitivity, large wavelength response rate and small volume. Therefore, the utility model discloses in select PIN type photodiode for use can detect the weak scattered light signal of particle more effectively and carry out the miniaturization.
The current/voltage conversion circuit is used for converting the current signal into a corresponding initial voltage signal.
The band-pass filtering amplifying circuit is used for amplifying the initial voltage signal.
The effective value conversion circuit is used for converting the amplified voltage signal to generate an effective voltage signal.
The A/D converter is used for converting the effective voltage signal into a corresponding mathematical signal for sampling and generating a voltage sampling signal.
The receiving performance of the receiving photodiode is strictly matched with the light emitting performance of the emitting photodiode of the LED, and the receiving spectral curve completely covers the emitting spectral curve of the emitting photodiode as much as possible.
FIG. 2 is a schematic representation of the measurement of sample water turbidity using two emitting photodiodes D and 4 receiving photodiodes LS1, LS 2. Wherein the emitting photodiode 111 and the emitting photodiode 112 are disposed at different positions of the cylindrical device 21 for emitting incident light of different frequencies into the sample water. The solid and dashed lines in fig. 2 are ray diagrams of incident light at two frequencies, respectively. The receiving photodiodes 121, 124 receive scattered light at positions 90 ° and 135 ° to the incident light emitted by the emitting photodiode 111, respectively, and the receiving photodiodes 123, 122 receive scattered light at positions 90 ° and 135 ° to the incident light emitted by the emitting photodiode 112, respectively. Wherein the emitting photodiode 111 and the emitting photodiode 112 may be disposed opposite to each other.
For avoiding the device ageing fast, the utility model discloses in two light source submodule periodic transmission incident lights. The two light source sub-modules can periodically and simultaneously emit incident light, and because of different frequencies, the two beams of incident light cannot affect each other. For improving the efficiency of measurement, the utility model discloses in can make two light source submodule piece periodic alternate emission incident light. Therefore, the continuity of the sampling data is ensured, and the problem of rapid aging of the device is avoided.
As shown in fig. 1, the turbidity meter of the present invention further includes a cleaning module 14 and a circulation module 15.
The cleaning module 14 is used for cleaning the light source module and the detection receiving module. The utility model discloses well cleaning module adopts high accuracy step motor to drive silica gel and washs the membrane head, and the location is accurate, guarantees that cleaning module can not disturb light path measurement system. And has the function of timing automatic cleaning, thereby further improving the accuracy of measurement.
The circulation module 15 is used for providing the sample water to be measured in real time and enabling the sample water to be measured to be in a circulation state. Specifically, the circulation module 15 is composed of a micro pump, a drain valve, a measurement cell, and a circulation line. The micro pump is controlled to pump sample water to be measured into the measuring tank through the flow pipeline, meanwhile, the drain valve is also opened, and the sample water is in a continuous flow state through the measuring tank, so that real-time online measurement of the sample water is achieved.
For the convenience to the frequency and the emission cycle of incident light adjust, the utility model provides a turbidity meter still includes a control module for to photodiode drive circuit send including the instruction of above-mentioned appointed frequency and cycle. So that the photodiode driving circuit generates a corresponding driving signal to drive the emitting photodiode according to the instruction.
Of course, the control module may also be connected to the washing module 14 and the flow-through module 15 for controlling them. Such as controlling when to initiate a cleaning process and a flow-through process, etc.
Certainly the utility model provides a turbidity meter still can include a power module to supply power to light source module, detection receiving module, cleaning module, circulation module and calculation module.
The utility model discloses well calculation module, power module and control module can be integrated together. The integrated module can use an ARM single chip microcomputer control system to be matched with an embedded operating system. The built-in standard turbidity curve is used for analyzing and processing measured data, and the method has the characteristics of high speed, low power consumption, strong real-time performance and the like. Meanwhile, an RS485 digital communication format and a standard MODBUS protocol are adopted, and special PC-side communication software or a secondary instrument is matched, so that the light source module and the like can be conveniently and visually calibrated, controlled and measured on site at the PC side, and the distance between cables can reach 500 meters.
Corresponding to the above embodiment, the second embodiment of the present invention provides a method for measuring turbidity of water, which is applied to the turbidity meter, and referring to fig. 3, the method includes:
s11, the light source module periodically emits two incident lights with different frequencies to the sample water to be measured.
For avoiding receiving the influence of natural light, the utility model discloses in the frequency of these two kinds of incident lights all is different from the frequency of natural light.
And S12, the detection receiving module receives the scattered light at the positions of 90 degrees and 130 degrees to 140 degrees with the incident light to generate a voltage sampling signal.
And S13, the calculation module calculates the turbidity of the sample water to be measured according to the voltage sampling signal.
Compared with the prior art, the utility model discloses in increased and be 130 ~ 140 degrees angle receipt scattered light with the incident light. This is because the influence of large particulate matter on incident light can be monitored to a greater extent at an angle of 130 ° to 140 ° than at other angles, and the turbidity of the sample water to be measured can be calculated more accurately. Preferably, the optimum angle is 135 ° to the incident light.
In a specific embodiment of the utility model, the light source module includes two light source submodule pieces, emits the incident light to the appearance water that awaits measuring respectively in the position of difference, and the frequency of the incident light of two light source submodule piece emissions is different. Correspondingly, the detection receiving module comprises four detection receiving sub-modules; the two detection receiving sub-modules respectively receive scattered light at positions which form 90 degrees and 130-140 degrees with incident light of one frequency; the other two detection receiving sub-modules respectively receive scattered light at positions of 90 degrees and 130 degrees to 140 degrees with incident light of another frequency.
Specifically, each light source submodule is composed of an emission photodiode, a parallel light lens group and a photodiode driving circuit. The process of emitting incident light by each light source sub-module includes:
the photodiode drive circuit sends a drive signal to the emitting photodiode, the drive signal containing a specified frequency.
The emitting photodiode emits incident light of a specified frequency to sample water to be measured according to the driving signal. Of course, the specified frequencies in the drive signals sent by the photodiode drive circuits in the two light source sub-modules are different.
According to international standard ISO7027, the light-emitting peak value of the emitting photodiode is generally selected to be about 860nm, and the emitting photodiode has high directivity, the half-value angle is selected to be 5-20 degrees, and the half-width of the spectrum is as small as possible, so that the unicity of the light-emitting wavelength is ensured.
The parallel light lens group focuses incident light emitted from the emitting photodiode.
Each detection receiving submodule consists of a receiving photodiode, a lens group, a current/voltage conversion circuit, a band-pass filtering amplification circuit, an effective value conversion circuit and an A/D converter. The process of receiving the scattered light by each detection receiving sub-module comprises the following steps:
the lens group focuses the scattered light signal onto the receiving photodiode.
The receiving photodiode converts the scattered light signals into corresponding current signals. The utility model discloses in, receive photodiode and can choose PIN type photodiode for use.
The current/voltage conversion circuit converts the current signal into a corresponding initial voltage signal.
The band-pass filtering amplifying circuit amplifies the initial voltage signal.
And the effective value conversion circuit converts the amplified voltage signal to generate an effective voltage signal.
The A/D converter converts the effective voltage signal into a corresponding mathematical signal for sampling, and generates a voltage sampling signal.
The receiving performance of the receiving photodiode is strictly matched with the light emitting performance of the emitting photodiode of the LED, and the receiving spectral curve of the receiving photodiode completely covers the light emitting spectral curve of the emitting photodiode as much as possible.
For avoiding the device ageing fast, the utility model discloses in two light source submodule periodic transmission incident lights. The two light source sub-modules can periodically and simultaneously emit incident light, and because of different frequencies, the two beams of incident light cannot affect each other. In order to improve the efficiency of measurement, in the utility model, two light source sub-modules can be enabled to periodically and alternately emit incident light. Therefore, the continuity of the sampling data is ensured, and the problem of rapid aging of the device is avoided.
For a turbidity instrument, the measured object is the turbidity of water, the change process is generally slow, and experiments prove that the scattered light intensity generated by bubbles in water changes, the value only can be increased but not reduced, namely the bubble interference has the characteristic of being unilateral. The bubbles cause light scattering enhancement, cause interference, do not reflect turbidity value of the water body and are removed. In addition, air bubbles and large particulate matters suddenly appearing in the water flow process influence the measurement stability and are removed, so that the measurement is more stable and accurate. For this purpose, step S13 includes a process of digitally filtering the received voltage sampling signal by the calculation module, and then measuring the turbidity of the sample water according to the filtered voltage sampling signal.
Wherein digitally filtering the received voltage sample signal comprises:
s21, averaging N voltage sampling signals in FIFO data window queue with length of N
S22, and the N voltage sampling signals are sequentially connected withComparisonAnd calling segmented weighted filtering processing to generate a corresponding data value, calculating the average value of the data values corresponding to the N voltage sampling signals, and calculating the turbidity value of the sample water to be measured according to the average value of the corresponding data values.
Wherein, step S22 includes:
sampling the Kth voltage with
Comparing, calling the sectional weighted filtering process to generate a data value D corresponding to the Kth voltage sampling signal DiThe piecewise weighting formula is
When D is present0<D<DjLet K = N, D be normal datai= D, the data value is fully applicable. When D is present<D0The sampled data values are smaller than those for zero turbidity water, which is not normally possible, and are discarded and re-sampled. When D is present>DjData values may contain interference components, processing, and order
For the disturbance caused by bubbles, there is no continuity and the measurement result cannot be influenced. For normally changing dataContinuity, has an effect on the mean value, allowing later data to fall into
Within the range, normal data is obtained.
Wherein K is ∈ [0, N ∈ >]，D0A sampled data value for 0 turbidity water; djThe maximum sampled data value that the nephelometer can monitor.
Under a certain environment, the turbidity value of the sample water is usually within a certain range, and a voltage sampling data value corresponding to the maximum turbidity value of the sample water under the environment can be obtained through a long-time experiment. Generally, the voltage sampling data value of the sample water in the environment should not be greater than the voltage sampling data value corresponding to the maximum turbidity value of the sample water in the environment. Accordingly, when D is above>DjThen give an order
<math><mrow>
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</mrow></math> The method comprises the following steps:
when D is presentj<D<DfThen give an order
When D is present>DfIf the bubble interference is present, then order
Wherein D isfAnd the sample data value is the sampling data value of the water with the highest turbidity under the environment where the sample water to be measured is located.
The utility model discloses well can use the moving average method management data to open length in the memory of singlechip and be N =23As a data buffer, a First Input First Output (FIFO) queue is established for storing sampled data, and the elements in the queue have d1，d2，d3，…d8. The new sampled data enter the queue from the tail of the queue in sequence, and meanwhile, the old data are dequeued from the head of the queue, so that the number of elements in the queue is kept unchanged all the time, the elements are calculated, the singlechip is convenient to program, and the quick division operation can be performed through shifting.
In an embodiment of the present invention, the turbidity meter further comprises a cleaning module and a circulation module. Correspondingly, the method further comprises the following steps:
the circulation module provides sample water to be measured in real time and enables the sample water to be measured to be in a circulation state.
And the cleaning module is used for cleaning the light source module and the detection receiving module.
For the convenience to the frequency and the emission cycle of incident light adjust, the utility model provides a turbidity meter still includes a control module. Correspondingly, the method further comprises the following steps: the control module sends an instruction comprising the specified frequency and the specified period to the photodiode driving circuit, so that the photodiode driving circuit generates a corresponding driving signal according to the instruction to drive the emitting photodiode. Of course, the control module may also be connected to the cleaning module and the flow-through module for controlling the same. Such as controlling when to initiate a cleaning process and a flow-through process, etc.
It should be noted that the embodiments of the apparatus and method of the present invention correspond, and the relevant portions may be referred to each other.
The above embodiments, further detailed description of the objects, technical solutions and advantages of the present invention, it should be noted that the above is only a specific embodiment of the present invention, and those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims and their equivalents, the present invention is also intended to include such modifications and variations.
Claims (10)
1. A turbidimeter is characterized by comprising a light source module, a detection receiving module and a calculation module;
the light source module is used for periodically emitting two incident lights with different frequencies to the sample water to be measured;
the detection receiving module is used for receiving scattered light at positions which form 90 degrees and 130-140 degrees with the incident light, generating a voltage sampling signal and sending the voltage sampling signal to the computing module;
the calculation module is used for calculating the turbidity of the sample water to be measured according to the voltage sampling signal.
2. A nephelometer according to claim 1, wherein the light source module comprises two light source sub-modules; the frequency and the incident position of incident light emitted by the two light source sub-modules are different;
the detection receiving module comprises four detection receiving sub-modules; the two detection receiving sub-modules respectively receive scattered light at positions which form 90 degrees and 130-140 degrees with incident light of one frequency; the other two detection receiving sub-modules respectively receive scattered light at positions which form 90 degrees and 130 degrees to 140 degrees with the incident light of the other frequency;
wherein,
each light source submodule consists of an emission photodiode, a parallel light lens group and a photodiode driving circuit;
the photodiode driving circuit is used for sending a driving signal to the emitting photodiode, and the driving signal comprises a specified frequency;
the emission photodiode is used for emitting the incident light with the specified frequency to the sample water to be measured according to the driving signal;
the parallel light lens group is used for focusing incident light emitted by the emitting photodiode;
and/or;
each detection receiving submodule consists of a receiving photodiode, a lens group, a current/voltage conversion circuit, a band-pass filtering amplification circuit, an effective value conversion circuit and an A/D converter;
the lens group is used for focusing scattered light signals onto the receiving photodiode;
the receiving photodiode is used for converting the scattered light signals into corresponding current signals;
the current/voltage conversion circuit is used for converting the current signal into a corresponding initial voltage signal;
the band-pass filtering amplifying circuit is used for amplifying the initial voltage signal;
the effective value conversion circuit is used for converting the amplified voltage signal to generate an effective voltage signal;
the A/D converter is used for converting the effective voltage signal into a corresponding mathematical signal for sampling and generating a voltage sampling signal.
3. A turbidity meter according to claim 2, wherein two of said light source sub-modules periodically alternate to emit incident light or two of said light source sub-modules periodically simultaneously emit incident light.
4. A nephelometer according to claim 2, further comprising a control module;
the control module is used for sending instructions to the photodiode driving circuit; the instructions include the specified frequency.
5. A nephelometer according to claim 4, wherein the control module and the calculation module are integrated on an ARM single chip microcomputer.
6. A nephelometer according to claim 2, further comprising a flow-through module and/or a wash module;
the circulation module is used for providing sample water to be measured in real time and enabling the sample water to be measured to be in a circulation state;
the cleaning module is used for cleaning the light source module and the detection receiving module.
7. A nephelometer according to claim 2 wherein the receiving photodiode has a receiving performance matched to the emitting performance of the corresponding emitting photodiode.
8. A nephelometer according to claim 2 wherein the receiving photodiode is a P-type photodiode.
9. A nephelometer according to claim 1, wherein the incident light has a frequency different from the frequency of natural light.
10. A nephelometer according to any of claims 1 to 9, wherein the detection receiving module is positioned at 90 ° and 135 ° to the incident light.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320733447.0U CN203643333U (en) | 2013-11-19 | 2013-11-19 | Turbidity meter |
Applications Claiming Priority (1)
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| CN201320733447.0U CN203643333U (en) | 2013-11-19 | 2013-11-19 | Turbidity meter |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103575705A (en) * | 2013-11-19 | 2014-02-12 | 苏州热工研究院有限公司 | Turbidity meter and measuring method for turbidity of water |
| CN108956546A (en) * | 2018-06-28 | 2018-12-07 | 深圳市美雅洁技术股份有限公司 | A kind of medical instrument cleaning system and method based on Turbidity measurement |
| WO2022198987A1 (en) * | 2021-03-23 | 2022-09-29 | 添可智能科技有限公司 | Turbidity measurement method, and cleaning device |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103575705A (en) * | 2013-11-19 | 2014-02-12 | 苏州热工研究院有限公司 | Turbidity meter and measuring method for turbidity of water |
| CN108956546A (en) * | 2018-06-28 | 2018-12-07 | 深圳市美雅洁技术股份有限公司 | A kind of medical instrument cleaning system and method based on Turbidity measurement |
| WO2022198987A1 (en) * | 2021-03-23 | 2022-09-29 | 添可智能科技有限公司 | Turbidity measurement method, and cleaning device |
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