Temperature sensor, microwave sensor and magnetic induction flow meter

Abstract

The invention relates to a temperature sensor (1) for ascertaining the temperature of a material to be measured, comprising:-an in particular metallic probe body (2) comprising:-an in particular at least partially conical measuring tip (3) designed to be in contact with the material to be measured; -a first probe receptacle (4), wherein the first probe receptacle (4) extends into the front portion (6) of the measuring tip (3); -a first probe holder (4) located in the end (7) of the probe body (2),-a second probe holder (5) located only in the end (7) of the probe body (2),-a first temperature probe (11) arranged in the first probe holder (4) and designed to determine a first measured value in which a contribution of the current temperature of the front prevails; and-a second temperature probe (12), which is arranged in the second probe receptacle (5) and is designed to determine a second measured value, in which a contribution of the current temperature of the end (7) prevails. The invention also relates to a microwave sensor and a magnetic inductive flowmeter.

Description

Technical Field

[0001] This invention relates to a temperature sensor for determining the temperature of a measuring material, and to a solids content for determining the solids content in a flowable, particularly water-containing, measuring material. Microwave sensors, and a magnetic induction flowmeter for identifying flow rate-related measurement variables of flowable, particularly conductive, measurement materials. Background Technology

[0002] Microwaves can be used to determine the physical variables of the dielectric constant and loss factor of the medium in a process line. From these two variables—measured at one or more different frequencies—conclusions can be drawn about the application of specific parameters, such as the proportion of water in a mixture of water and other nonpolar or weakly polar components, or the solid content in a liquid medium.

[0003] The established transmission / reflection measurement method is described in "Microwave Electronics, Measurement and Materials Characterization" by LFChen, CKOng, CPNeo, VVVaradan, and VKVaradan, John Wiley & Sons Ltd., 2004. For this purpose, scattering parameters (transmission and optionally reflection) are measured between microwave signal interfaces at two different locations within the medium in a container or measuring tube, and the stated physical properties of the medium are calculated from the measured scattering parameters.

[0004] WO 2018 121927 A1 teaches a measuring assembly for analyzing the properties of a flowing medium using microwaves. In addition to a microwave antenna, the measuring assembly has an electrically insulating lining layer on the inner circumferential surface of a measuring tube. This lining layer forms a dielectric waveguide through which at least a portion of a microwave signal can travel from a first microwave antenna to a second microwave antenna. One application of this measuring assembly is determining the solids content in a transmitted liquid medium. WO 2021 / 099152 A1 teaches a microwave antenna having a front portion that contacts the measured material, through which an excitation signal is emitted into the medium. To determine the solids content, a complex model dependent on the actual temperature of the measured material is required. This necessitates precise temperature measurements.

[0005] Magnetic induction flow meters are used to determine the flow rate and volumetric flow rate of a medium flowing in a pipe. A magnetic induction flow meter has a magnetic field generating device that generates a magnetic field perpendicular to the flow direction of the medium. A single coil is typically used for this purpose. To achieve a predominantly uniform magnetic field, pole pieces are additionally formed and attached such that the magnetic field lines extend across the entire cross-section of the pipe, substantially perpendicular to the transverse axis or parallel to the vertical axis of the measuring tube. Furthermore, the magnetic induction flow meter has a measuring tube on which the magnetic field generating device is arranged. Measuring electrodes, attached to the outer circumferential surface of the measuring tube or arranged within electrode openings in the measuring tube, tap an electrical measurement voltage or potential difference applied perpendicular to the flow direction and the magnetic field, and this voltage or potential difference occurs as the conductive medium flows through the applied magnetic field in the flow direction. Since the tapped measurement voltage depends on the velocity of the flowing medium according to Faraday's law of induction, the flow rate and—including the known pipe cross-section—volumetric flow rate can be determined from the measured induction voltage.

[0006] Magnetic induction flow meters are commonly used in fluid processes and automation engineering, starting with conductivity of approximately 5 μS / cm. Corresponding flow meters are sold by the applicant in various embodiments for various application areas—for example, under the name PROMAG. For specific applications, in addition to volumetric flow rate, information about the temperature and / or conductivity of the measured material is required, as this is strongly temperature-dependent.

[0007] DE 102012109308 A1 describes a fill level monitoring system for magnetic induction flowmeters, which has an electrode for monitoring the fill level of the flowing medium in the pipe, and the electrode has an integrated temperature sensor. A drawback of this solution is the thermal coupling between the electrode and the interior of the housing, which can lead to distortion in the temperature measurement. Summary of the Invention

[0008] The purpose of this invention is to provide an improved temperature determination method.

[0009] This objective is achieved through temperature sensors, microwave sensors, and magnetic induction flow meters.

[0010] A temperature sensor for determining the temperature of a measuring material according to the present invention comprises:

[0011] -Including, in particular, the metal probe body:

[0012] -In particular, the measuring tip is at least partially conical, extending into the front part of the measuring tip;

[0013] - The second probe housing, located within the probe body.

[0014] - A first temperature probe is positioned and designed to determine a first measurement value.

[0015] In the first measurement, the current temperature at the front contributes the most; and

[0016] - A second temperature probe is arranged and designed to determine a second measurement value.

[0017] In the second measurement, the current temperature at the end point is the dominant factor.

[0018] Advantageous embodiments of the present invention are the subject of the dependent claims.

[0019] One embodiment provides a temperature sensor, particularly a probe body, to further include:

[0020] - A sealing device receiving portion for receiving a sealing device positioned between the front and the end portions.

[0021] The second probe receiving portion extends no more than the sealing device receiving portion.

[0022] One embodiment provides a first probe receiver and / or a second probe receiver, each at least partially connected via an electrical conductor to a thermal paste having four pins.

[0023] Two of the other pins are each electrically connected to the second temperature probe via an electrical conductor.

[0024] One embodiment provides a temperature probe, particularly a probe body, to further include:

[0025] -The contact surface, which is positioned between the front and the end.

[0026] The second probe receiving portion extends no more than the contact surface.

[0027] The solids content of a flowable, particularly aqueous, measuring material according to the present invention is used to determine the solids content of the material. Microwave sensors, including:

[0028] - Measuring tubes used for conducting measurement materials;

[0029] - A transmitting antenna, which is used to generate microwave signals that pass through the measuring material;

[0030] - A receiving antenna, used to receive microwave signals passing through the measuring material;

[0031] - The outer shell dominates;

[0032] - Evaluate electronic devices, which are further designed to determine the solid content as a function of a first measurement and a second measurement. .

[0033] One embodiment provides a first temperature probe and a second temperature probe as part of a temperature sensor according to the invention.

[0034] One embodiment provides that the evaluation electronics are designed to determine the compensated temperature of the measuring material as a function of a first measurement and a second measurement.

[0035] A magnetic induction flowmeter according to the present invention for determining flow rate-related measurement variables of flowable, particularly conductive, measuring materials, comprises:

[0036] - Measuring tubes used for conducting measurement materials;

[0037] - A housing used to determine the induced voltage in a measuring material;

[0038] - A magnetic field generating device used to generate a magnetic field that passes through a measuring tube;

[0039] - A temperature sensor according to the invention, arranged at least partially in a magnetic field generating device.

[0040] One embodiment provides for designing a temperature sensor as a measuring electrode, a fill level monitoring electrode, or a reference electrode. Attached Figure Description

[0041] The invention will be explained in more detail with reference to the following figures, in which:

[0042] Figure 1 A longitudinal section of the temperature sensor according to the present invention is shown;

[0043] Figure 2 A perspective view of a microwave sensor according to the present invention is shown;

[0044] Figure 3 A cross-section of another embodiment of the microwave sensor according to the present invention is shown; and

[0045] Figure 4 A cross-section of a magnetic induction flowmeter according to the present invention is shown. Detailed Implementation

[0046] Figure 1 A longitudinal section of a temperature sensor 1 according to the invention for determining the temperature of a measuring material is shown. The sensor 1 includes a probe body 2, which may be made of metal. The probe body 2 is preferably made of a material having good thermal conductivity, i.e., >1 W / (mK). Suitable materials may be, for example, steel. The probe body 2 shown is rotationally symmetrical at least in a portion (i.e., in the front).

[0047] In the illustrated embodiment, the probe body 2 has a partially conical measuring tip 3. Alternatively, the measuring tip 3 can also take different shapes, such as cylindrical. The measuring tip 3 is designed to contact the material to be monitored. Especially for applications where the measuring material has a solid content, it is important to have a stable measuring tip 3 and good thermal contact between the measuring material and the temperature probe. For this purpose, the illustrated solution has a minimum thickness of 0.5 mm, and particularly at least 1 mm and at most 10 mm.

[0048] The probe body 2 has a first probe receiving portion 4 extending into the front portion 6 of the measuring tip 3. When the temperature sensor 1 is used, the front portion 6 contacts the measuring material and surrounds the center of the measuring tip 3, to which the probe body 2 is shown tapering.

[0049] A first temperature probe 11 is disposed in a first probe housing 4. The temperature probe 11 may be a resistance thermometer (PT100 or PT1000) or a thermocouple. The first temperature probe 11 is designed to determine and provide a first measured value. The first measured value is the current temperature at the temperature probe or a value proportional to it (e.g., resistance). The determined current temperature consists of several contributions. The first temperature probe 11 is positioned such that the current temperature at the front end dominates the contribution of the first measured value, and therefore, when a temperature sensor is used, the current temperature of the measuring material in thermal contact with the front end dominates the contribution of the first measured value.

[0050] The probe body 2 also includes a second probe receiving portion 5, which is located only in the end portion 7 of the probe body 2. The end portion 7 does not contact the measuring material, and when the temperature sensor 1 is mounted on a container or pipe, the end portion 7 is located outside the portion of the container or pipe where the measuring material is located. This means that the second probe receiving portion 5 is spaced apart from the first probe receiving portion 4 in the longitudinal direction of the probe body 2. When the longitudinal axis of the probe body 2 passes through the first probe receiving portion 4, the second probe receiving portion 5 is arranged to be radially offset from the longitudinal axis of the probe body 2.

[0051] A second temperature probe 12 is arranged in the second probe housing 5 and designed to determine a second measurement value. The second measurement value is also the current temperature at the temperature probe or a value proportional to it (e.g., resistance). It also has several contributions. The contribution of the current temperature at end 7 is dominant.

[0052] The second measurement can be used to correct the temperature of the measured material determined based on the first measurement. This is especially important when the ambient temperature at the measurement point differs from the temperature of the medium, as the determined temperature value may differ from the actual temperature of the measured material.

[0053] If the ambient temperature, and therefore the temperature exposed by the second temperature probe 12, is significantly lower than the temperature of the material being measured, then the temperature value determined using the first temperature probe 11 is also significantly lower than the actual temperature of the material being measured.

[0054] If the ambient temperature, and therefore the temperature exposed by the second temperature probe 12, is significantly higher than the temperature of the material being measured, then the temperature value determined using the first temperature probe 11 is also significantly higher than the actual temperature of the material being measured.

[0055] This is because the first temperature probe 11 is not completely thermally decoupled from the environment. Therefore, using the second temperature probe 12 has the following advantages: it can measure the influence of the ambient temperature that leads to erroneous measurements, and the temperature value obtained using the first temperature probe 11 can be corrected by identifying the influence.

[0056] The above describes a static scenario. However, using the second temperature probe 12 also has advantages in dynamic situations. If the temperature of the measured material changes, this is measured by the first temperature probe 11 in the front section. The ambient heat capacity has not yet reached the temperature of the measured material, and therefore slightly affects the measurement value of the first temperature probe 11. This leads to measurement error. The second temperature probe 12 in the end section also measures inaccurately due to temperature changes. However, this is more delayed compared to measurements using the first temperature probe due to lower thermal coupling with the measured material. As the temperature increases, a difference arises between the measurements taken at the two temperature probes. The resulting difference can be used for correction purposes.

[0057] The temperature sensor 1 or probe body 2 shown has a sealing device receptacle 10 for receiving a sealing device 9. In the illustrated embodiment, the sealing device 9 is a sealing ring. However, other sealing devices—such as a sealing fluid applied in liquid form—are also suitable. Standardized seals specifically designed for the intended application are suitable as the sealing device 9. The sealing device receptacle 10 is positioned between the front portion 6 and the end portion 7. When in use, the sealing device 9 contacts the wall of the container or pipe in which the temperature sensor 1 is inserted. In order to be able to detect the influence of the environment on the temperature measurement, it is important that the two temperature probes are as far apart as possible, or that the second temperature probe is as far apart as possible from the measuring tip. In the illustrated embodiment, the second probe receptacle 5 extends no more than the sealing device receptacle 10. The sealing device receptacle 10 itself is designed as a groove extending circumferentially around the probe body 2.

[0058] In order to achieve optimal thermal coupling between temperature probes 11 and 12 and the corresponding parts to be monitored, the first probe housing 4 and the second probe housing 5 are at least partially filled with thermal paste 8, particularly silicone paste.

[0059] The probe body 2 is provided with a protective cover 13 covering the interior of the probe body 2. The protective cover 2 has four pins 14 (only two pins are shown in the perspective view). Two pins are each electrically connected to a first temperature probe 11 via a conductor, and the other two pins are each electrically connected to a second temperature probe 12 via a conductor. The protective cover 13 is integrally attached to the probe body 2 at an end 7. This can be accomplished, for example, by means of a soldering method. Alternatively, the connection between the protective cover 13 and the probe body 2 can also be achieved by form-fit and / or force-fit connection.

[0060] In the illustrated embodiment or in an embodiment where the sealing device is explicitly omitted, the temperature sensor 1 or probe body 2 has a contact surface 15 designed to function as a stop. If the probe body 2 is made of metal and the container or pipe is also metal, sufficient sealing can be achieved even without a sealing device by selecting a suitable (e.g., tapered) contact surface 15. In this case, the contact surface 15 is positioned between the front portion 6 and the end portion 7, and the second probe receiving portion 5 extends beyond the contact surface 15.

[0061] The illustrated embodiment of the probe body 2 has an external thread 20, through which the temperature sensor 1 can be screwed into an opening with an internal thread. The probe body also has a hexagonal portion that forms part of the end portion 7.

[0062] The two electrical connectors that connect the corresponding temperature probes to the pins each have ceramic sleeves 30 that prevent them from contacting the thermal paste 8.

[0063] The protective cover 13 has an electrical insulator 40 in which four pins are arranged. The front of each pin is located in a cavity formed by the protective cover 13 and the probe body 2. The ends of each pin point away from the probe body 2. Pins 14 are connected to the evaluation electronics via electrical conductors (e.g., twisted pairs) to establish an electrical connection between the two temperature probes 11 and 12 and the evaluation electronics. The four pins 14 are encapsulated with an electrical insulating potting compound 50. This compound provides stress relief to the electrical conductors relative to the wires contacting the two temperature probes.

[0064] Figure 2 A perspective view of a microwave sensor 100 according to the present invention is shown. The microwave sensor 100 is used to determine the solid content of solids in a flowable, particularly aqueous, measuring material. In the application of microwave sensor 100, the measured material is transported in the production line via measuring tube 101.

[0065] The microwave sensor 100 shown includes a transmitting antenna 116 for generating a microwave signal that passes through the medium when a measuring material is present in the measuring tube 101. The transmitting antenna 116 is arranged in an opening in the measuring tube 101. A suitable transmitting antenna 116 is disclosed in patent specification DE10 2020 134 320 A1, the entire contents of which are incorporated herein by reference.

[0066] The microwave sensor 100 also includes a receiving antenna 118 for receiving microwave signals generated by the transmitting antenna 116 and passing through the medium when the medium is present in the measuring tube 101. A suitable receiving antenna 118 is also disclosed in patent specification DE 10 2020 134 320 A1, the entire contents of which are incorporated herein by reference.

[0067] Alternatively, the microwave sensor 100 may have only one antenna, which is both a receiving antenna 118 and a transmitting antenna 116. In this case, the microwave signal is generated by the antenna and is also measured. For this purpose, the microwave signal is reflected at least once on the inner circumferential surface of the measuring tube in the direction of the transmitting antenna.

[0068] The electronic components used to connect the receiving antenna 118 and the transmitting antenna to the evaluation electronics 102 are typically protected from external influences by a housing (not shown).

[0069] The microwave sensor 100 also includes a first temperature probe 111, which is designed to determine a first measurement and provide it to evaluation electronics. The first temperature probe 111 is positioned on or within the measuring tube 101, enabling thermal coupling between the measuring material and the first temperature probe 111. Therefore, the contribution from the current temperature of the measuring material dominates the first measurement.

[0070] According to the invention, the microwave sensor 100 has a second temperature probe 112 designed to determine a second measurement value. The second temperature probe 112 is arranged significantly away from the measuring tube 101 such that the main contribution to the second measurement value is caused by the current temperature in the housing.

[0071] Evaluation electronics 102, which may also be arranged in the housing or external transmitter housing, are designed to determine the solid content as a function of the provided propagation time and / or the absorption of the received microwave signal. In order to determine the solid content as accurately as possible. When determining the solids content, the temperature dependence of the dielectric constant of water must be considered. For this purpose, according to the present invention, the evaluation electronics 102 is designed to determine the solids content as a function of a first measurement value and a second measurement value. .

[0072] The compensation temperature of the measuring material can not only be correlated with the measurement accuracy as the solid content increases, but can also be displayed to the customer, for example, on a monitor. For this purpose, the evaluation electronics 102 is designed to determine the compensation temperature of the measuring material as a function of the first and second measured values.

[0073] Figure 3 A cross-section of another embodiment of the microwave sensor 100 according to the invention is shown. The illustrated embodiment includes a temperature sensor 1 according to the invention, which is arranged in an opening provided for this purpose in the measuring tube 101, specifically screwed into the opening. A transmitting antenna 116 for generating microwave signals passing through the measuring material and a receiving antenna 118 for receiving microwave signals passing through the measuring material are also arranged in corresponding openings in the measuring tube 101. The temperature sensor 1, the transmitting antenna 116, and the receiving antenna 118 are arranged in a housing 120, which is designed to protect them from external influences. If the measuring material conducts through the measuring tube 101 and if the temperature sensor 1 is in contact with the measuring material, the contribution of the current temperature of the measuring material dominates the first measurement value determined using a first temperature probe. The temperature in the housing 120 also affects the first temperature value, but this contribution is significantly less than that of the measuring material. The second measurement value determined by means of a second temperature probe 112 is dominated by the current temperature in the housing 120. Especially for large temperature differences, the temperature of the measuring material also contributes significantly, as it heats or cools the interior of the housing.

[0074] Figure 4 A cross-section of a magnetic induction flowmeter 200 according to the present invention is shown. The structure and measurement principle of the magnetic induction flowmeter 200 are known in principle. A flowable measuring material (or medium) with sufficiently high conductivity is conducted through a measuring tube 202. The measuring tube 202 includes a carrier tube 203, which is typically made of steel, ceramic, plastic, or glass, or at least includes steel, ceramic, plastic, or glass. To prevent the measuring voltage induced in the medium from dissipating via the conductive carrier tube 203, the inner wall is lined with an insulating material, such as a (plastic) lining 204 or ceramic tile.

[0075] A magnetic field generating device 205 is arranged on a carrier tube 203 such that the magnetic field lines are oriented substantially perpendicular to the longitudinal direction defined by the axis of the measuring tube. The magnetic field generating device 205 typically includes at least one saddle-shaped coil or at least one coil 213 having a coil core 214. Figure 4In the illustrated embodiment, the magnetic induction flowmeter 200 has two radially arranged coils 213, each having a coil core 214 and a pole piece. The two coil cores 214 are connected to each other via a field loop 222, specifically a magnetic connection. A field return 222 connects opposite sides of the coil cores 214 to each other. However, magnetic induction flowmeters 200 with exactly one coil 213 and no field return 222 are also known, where the single coil 213 has exactly one coil core 214. Furthermore, magnetic induction flowmeters 200 with saddle-shaped coils in which no coil core is arranged are also known. The coil 213 is connected to an operating circuit 207, which operates the coil 213 by means of an operating signal. The operating signal can be a voltage with a time-varying curve, and is characterized by operating signal parameters, wherein at least one of the operating signal parameters is controllable. The magnetic field generated by the magnetic field generating device 205 is generated by means of pulsed direct current of alternating polarity provided by the operating circuit 207. This ensures a stable zero point and makes the measurement insensitive to effects caused by electrochemical interference. The two coils 213 can be connected to the operating circuit 207 respectively, or connected in series or in parallel with each other.

[0076] When a magnetic field is applied, a flow-dependent potential distribution is generated in the measuring tube 202, which can be detected, for example, in the form of an induced measurement voltage. A device for tapping the induced measurement voltage is arranged on the measuring tube 2. In the illustrated embodiment, the device for tapping the induced measurement voltage consists of two opposing measuring electrodes 217, 218, which establish current contact with the medium and are each arranged in a corresponding electrode opening. However, a magnetic induction flowmeter 200 is also known, which includes measuring electrodes arranged on the outer wall of the carrier tube 203 that do not contact the measuring material. The measuring electrodes 217, 218 are generally arranged diametrically and form an electrode axis, or intersect a transverse axis extending perpendicular to the magnetic field lines and the longitudinal axis of the measuring tube 202. However, devices designed to tap the induced measurement voltage and having more than two measuring electrodes are also known. Flow rate-dependent measurement variables can be determined based on the measured voltage. Flow rate-dependent measurement variables include the flow rate of the medium, volumetric flow rate, and / or mass flow rate. Evaluation electronics 207 is designed to detect the induced measurement voltage applied to measurement electrodes 217, 218 and to determine the flow rate-related measurement variable as a function of the measurement voltage. The illustrated measurement electrodes 217, 218 are shown in simplified form only. According to the invention, evaluation electronics 207 is designed to determine the corrected temperature and / or conductivity of the measurement material as a function of a first measurement value and a second measurement value.

[0077] In addition to measuring electrodes 217 and 218, commercially available magnetic induction flow meters also have two additional electrodes. In the first case, a fill level monitoring electrode, optimally attached to the highest point of the measuring tube 202, is used to detect partial filling of the measuring tube 202 and is designed to convey this information to the user and / or take the fill level into account when determining the volumetric flow rate. Additionally, a reference electrode 233, typically attached along the diameter of the fill level monitoring electrode or at the lowest point of the measuring tube cross-section, is used to establish a controlled potential in the medium. Typically, the reference electrode 233 is used to connect the flowing medium to a ground electrode.

[0078] According to the present invention, the magnetic induction flowmeter has a temperature sensor 1 disposed in a lateral opening in the outer peripheral surface of the measuring tube. In the illustrated embodiment, the temperature sensor 1 is at least partially disposed in the magnetic field generating device 205 and additionally serves as a filler horizontal monitoring electrode. Alternatively, the temperature sensor 1 may also be disposed offset in the flow direction from the measuring plane in which the magnetic field generating device 205 and the measuring electrodes 217, 218 are located. Alternatively, the temperature sensor 1 may be designed as a measuring electrode or a reference electrode.

Claims

1. A temperature sensor (1) for ascertaining the temperature of a measuring material, comprising: - a probe body (2), in particular of metal, which comprises: - a measuring tip (3), in particular at least partially conical, which is designed to come into contact with the measuring material; - a first probe receptacle (4), wherein the first probe receptacle (4) extends into a front portion (6) of the measuring tip (3); - a second probe receptacle (5), which is located only in an end portion (7) of the probe body (2), - a first temperature probe (11), which is arranged in the first probe receptacle (4) and is designed to determine a first measurement value, wherein in the first measurement value the contribution of the current temperature of the front portion predominates; and - a second temperature probe (12), which is arranged in the second probe receptacle (5) and is designed to determine a second measurement value, wherein in the second measurement value the contribution of the current temperature of the end portion (7) predominates.

2. The temperature sensor (1) according to claim 1, further comprising: - a sealing device receptacle (10) for receiving a sealing device (9), in particular a sealing ring, wherein the sealing device receptacle (10) is positioned between the front portion (6) and the end portion (7), wherein the second probe receptacle (5) extends no further than the sealing device receptacle (10).

3. The temperature sensor (1) according to claim 1 or 2, wherein wherein the first probe receptacle (4) and / or the second probe receptacle (5) is / are at least partially filled with a thermal paste (8), in particular a silicone paste, and preferably a silicone rubber.

4. The temperature sensor (1) according to any one of the preceding claims, further comprising: - a protective cover (13) having four pins (14), wherein two pins are each electrically connected to the first temperature probe (11) via an electrically conductive body, wherein two further pins are each electrically connected to the second temperature probe (12) via an electrically conductive body.

5. The temperature sensor (1) according to any one of the preceding claims, further comprising: - a contact surface (15) designed to serve as a stop, wherein the contact surface (15) is positioned between the front portion (6) and the end portion (7), wherein the second probe receptacle (5) extends no further than the contact surface.

6. A method for determining the solids content in a flowable, particularly aqueous, measuring material. The microwave sensor (100) includes: - a measuring tube (101) for conducting the measuring material; - a transmitting antenna (116) for generating a microwave signal through the measuring material; - a receiving antenna (118) for receiving a microwave signal through the measuring material; - a housing (120); - a first temperature probe (111) designed to determine a first measurement value, wherein, in the first measurement value, the contribution of the current temperature of the measurement material is dominant; - a second temperature probe (112) designed to determine a second measurement value, wherein, in the second measurement value, the contribution of the current temperature in the housing (120) is dominant; - evaluation electronics (102) designed to ascertain the solids content as a function of the provided propagation times and / or the received absorption of the microwave signals , wherein the evaluation electronics (102) is further designed to ascertain the solids content as a function of the first measurement value and the second measurement value .

7. Microwave sensor (100) according to claim 6, wherein wherein, the first temperature probe (11, 111) and the second temperature probe (12, 112) are part of a temperature sensor (1) according to any one of claims 1 to 7.

8. Microwave sensor (100) according to claim 6 or 7, wherein wherein the evaluation electronics (102) are designed to ascertain a compensated temperature of the measurement material as a function of the first measurement value and the second measurement value.

9. Magnetic-inductive flowmeter (200) for ascertaining a flow rate-dependent measurement variable of a flowable, in particular electrically conductive, measurement material, comprising - a measurement tube (202) for conducting the measurement material; - a housing (220); - at least two measurement electrodes (217, 218) for ascertaining a measurement voltage induced in the measurement material; - a magnetic field generating device (205) for generating a magnetic field through the measurement tube (202); - a temperature sensor (1) according to any one of claims 1 to 5; - evaluation electronics (207) designed to ascertain a corrected temperature and / or an electrical conductivity of the measurement material as a function of a first measurement value and a second measurement value.

10. Magnetic-inductive flowmeter according to claim 9, wherein wherein the temperature sensor (1) is at least partially arranged in the magnetic field generating device (205).

11. Magnetic-inductive flowmeter according to claim 9 or 10, wherein wherein the temperature sensor (1) is designed as a measurement electrode, a fill level monitoring electrode or a reference electrode.

Images