Apparatus and method for monitoring portable grounding devices

Abstract

The present invention relates to an apparatus 202 and method for monitoring a mobile grounding device 102. The apparatus 202 comprises a first pole 204 for connection to the mobile grounding device 102, a second pole 206 for connection to a reference probe 208, and a control device. The control device is configured to sense an electrical resistance between the first pole 204 and the second pole 206 and compare it with a threshold value. The control device outputs a status signal based on the comparison between the electrical resistance and the threshold value.

Description

[Technical Field]

[0001] [Related Applications] This international application claims priority to German Patent Application No. 102023105307.8, filed March 3, 2024, which is incorporated herein by reference in its entirety.

[0002] The present disclosure relates to an apparatus and method for monitoring a mobile grounding device. [Background technology]

[0003] When pouring, discharging, pumping, mixing, spraying, measuring, sampling, or cleaning liquids, granules, or powders, the containers involved or the materials themselves may become electrically charged, the amount of which depends on several factors, such as the method of operation, the characteristics and flow rate of the material being treated, and the size, geometry, and material of the container. Summary of the Invention

[0004] An apparatus and method for monitoring a mobile grounding device is disclosed, substantially as shown by and described in connection with at least one of the drawings, and as more fully set forth in the claims.

[0005] Examples of the present disclosure are described in further detail below with reference to the drawings. [Brief explanation of the drawings]

[0006] [Figure 1] 1 is a schematic diagram of a mobile grounding device according to the prior art;

[0007] [Figure 2] 1 is a schematic diagram of a grounding fixture with an apparatus for monitoring a mobile grounding fixture according to one embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0008] As a result of the above-mentioned electrostatic charging of the container and / or the filling, undesirable and uncontrolled discharges may occur during dispensing and refilling, which may lead to various problems. On the one hand, these discharges may interfere with the dispensing or refilling process. On the other hand, as a more serious consequence, electrical equipment connected to the container (e.g., an electric balance) may be damaged. Finally, uncontrolled discharges may also cause fires, especially when handling highly flammable substances.

[0009] To overcome such problems, it is known to use earthing systems which ensure safe earthing and controlled discharge of the associated vessels.

[0010] In addition to protecting the systems mentioned above, earthing is also used to protect personnel, particularly from fault current leakage, lightning effects, electrostatic discharges, and electromagnetic interference. This is also called protective earthing. In particular, mobile equipment, e.g., emergency power packs, when used outdoors are often required to be connected to an equipotential bonding / protective earth. Unlike similar equipment used within buildings or other fixed installations, there are usually no mandatory tested earth conductors or equipotential bonding conductors. In that case, earthing / equipotential bonding must be established by a mobile earth point.

[0011] The above-mentioned mobile devices are often used, for example, by fire brigades / disaster response teams. To ensure adequate grounding, first aid personnel insert mobile grounding points, such as ground rods, into the existing ground on-site. For this purpose, the ground rods can be, for example, driven or screwed in. In this situation, especially during an emergency call, there is little time to insert the grounding points into the ground or to verify the reliability of the grounding. Even if suitable measuring equipment and time are available, only random measurements are performed.

[0012] Adequate grounding using a portable grounding point depends on many factors. For example, the conductivity of a portable grounding device not only depends on how securely the grounding device is fixed to the ground (earth), but the composition of the ground also plays a major role. Therefore, dry ground is less conductive than wet ground. Also, the composition of the ground is not always immediately apparent to the user when driving in a portable grounding device. For example, a gravel layer located below the ground surface can reduce conductivity, but the user may not be aware of this.

[0013] Based on the above situation, the present disclosure addresses the problem of identifying an apparatus and method for monitoring mobile grounding devices that can quickly and reliably determine the conductivity of the mobile grounding devices. The apparatus according to the present disclosure is intended to be mobile and can be easily used in the field with known mobile grounding devices.

[0014] This above-mentioned problem is solved according to the present disclosure by the subject matter of independent claims 1 and 12. Further developments of the disclosed device or the disclosed method for monitoring mobile grounding devices can be found in the dependent claims.

[0015] Accordingly, the present disclosure relates to an apparatus and method for monitoring a mobile grounding device, the apparatus comprising a first pole for connecting to the mobile grounding device, a second pole for connecting to a reference probe, and a control device, the control device being configured to detect an electrical resistance between the first pole and the second pole, compare the electrical resistance with a threshold value, and output a status signal based on the comparison between the electrical resistance and the threshold value.

[0016] The present disclosure is based on the finding that the conductivity of a grounding device is directly proportional to the resistance in the ground between the grounding device and the reference probe. For this reason, in addition to a mobile grounding device, e.g., a ground rod, a reference probe is also inserted into the ground. The reference probe can also be a ground rod. The ground rods of the grounding device and the reference probe can be identical or designed with different dimensions. It should be noted that the resistance measured by the device according to the present disclosure corresponds to the leakage resistance of the "inferior" (e.g., smaller) ground rod.

[0017] The two poles of the device for monitoring the mobile grounding device can be connected to the mobile grounding device on one hand and to a reference probe on the other hand to determine the electrical resistance between the two ground rods, i.e., between the mobile grounding device and the reference probe. Under ideal starting conditions, the resistance between the reference probe and the mobile grounding device can be assumed to substantially correspond to the leakage resistance to the ground. As long as the electrical resistance thus detected is below a threshold, the control unit outputs a grounding success signal through the device, which can be used to notify the user that electrical conductivity is adequate and work can begin. If the electrical resistance thus detected exceeds a threshold, the device outputs a warning signal, which can be used to notify the user that electrical conductivity is insufficient and therefore there is a risk of injury / burns. For example, the device can be associated with an optical status indicator to indicate the status signal. In response to the grounding success signal, the visual status indicator can be illuminated (e.g., green). In response to the warning signal, the light on the visual status indicator can be turned off or displayed in a different color (e.g., red). The user can then attempt to readjust the portable grounding fixture to achieve sufficient conductivity and therefore bring the resistance between the reference probe and the portable grounding fixture below a threshold value.

[0018] According to a further embodiment, the control device is configured to continuously or at regular intervals detect the electrical resistance between the first and second poles. Thus, the device not only ensures sufficient conductivity of the portable grounding device during insertion, but also ensures the safety of the user throughout use. For example, the control device can be configured to emit a measurement signal at predetermined intervals to detect the electrical resistance between the two poles. Alternatively, the resistance measurement can be performed continuously. Therefore, the device for monitoring the portable grounding device can be envisioned to provide the user with continuous feedback about the conductivity of the grounding device. This allows the device to provide positive feedback until a threshold is exceeded. This allows the user to rule out the possibility that the absence of a warning signal is simply due to a malfunction of the device.

[0019] According to a further embodiment, the device comprises warning means for optically and / or acoustically outputting the first warning signal. For example, the warning means can be an illumination means, such as an LED, that visually informs the user that the threshold has been exceeded. Thus, the illumination means can light up red when the threshold is exceeded. Until the threshold is exceeded, the illumination means can be, for example, green. Naturally, any other color combination is also possible. In one design variant, when the threshold is exceeded, the illumination means switches off, i.e., the green light switches off, alerting the user. Alternatively, the device of the present disclosure can comprise a speaker that emits a warning sound when the control device outputs the first warning signal. Naturally, this has the advantage that the user does not need to be within the line of sight of the device to perceive the first warning signal.

[0020] According to a further embodiment, the threshold value is less than the maximum standard requirement for the particular application. Accordingly, the control device may be configured to receive application data indicative of the application of the portable grounding fixture and to set the threshold value based on the application data.

[0021] In this regard, it is noted that different leakage resistances are acceptable under different application conditions. For example, for controlled discharge of surface charges, achieving a leakage resistance of approximately 10 kΩ may be sufficient. In contrast, for protective grounding of, for example, a generator, it may be necessary to achieve a leakage resistance of less than 10 Ω or even less than 0.5 Ω. However, it should be noted that these leakage resistances are merely exemplary values ​​and are not intended to limit the present disclosure. Rather, the control device is configured to detect the application case based on application data (e.g., input from a user or automatic detection of connected objects / equipment) and adjust the thresholds accordingly. Thus, the control device may generally set the thresholds higher when a mobile grounding device is used for discharge of surface charges and lower when a mobile grounding device is used for protective grounding. Each threshold for each application case may be a default setting for the device, which may be individually set in embodiments described in more detail below.

[0022] According to further embodiments, the device can be battery-powered or connected to an external power source, and the control device can be configured to apply an intrinsically safe voltage to the electrodes for detecting the resistance. The term "intrinsically safe" refers to explosion protection. There is no such thing as an intrinsically safe voltage, nor is there such thing as an intrinsically safe current; only the product of the two can be intrinsically safe. In other words, the control device can control the measured voltage so that the product of voltage and current does not exceed the maximum power. A measured voltage controlled in this way can be called "intrinsically safe." The device of the present disclosure not only operates in the 230V range, but also provides reliable measurement results in the 4.5V to 12V range. Therefore, the device is easily portable and can be used essentially anywhere.

[0023] According to a further embodiment, the control device comprises a control terminal connectable to the equipment to be grounded, and the control device is configured to output a release signal to the control terminal when the electrical resistance is below a threshold and / or to output an emergency stop signal to the control terminal when the threshold is exceeded. In other words, according to this design variant, the control device can generate a control signal instead of or in addition to a status signal as soon as the threshold is exceeded. The emergency stop signal can be sent via the control port to the equipment to be grounded, such as emergency power packs, and can switch them off as soon as the threshold is exceeded. Thus, the device according to this embodiment does not depend on the user's attention or reaction time. Rather, the device can automatically ensure that the connected mobile equipment can only operate if reliable electrical conductivity is ensured. Alternatively or additionally, the control device can provide a release signal for operation of the equipment to be grounded as long as the electrical resistance is below a threshold.

[0024] According to a further embodiment, the control device is configured to receive grounding appliance data indicative of the grounding appliance used and to set the threshold value based on the grounding appliance data.

[0025] According to this embodiment, the device of the present disclosure can be configured based on the application case. For example, grounding device data can be entered by a user. For this purpose, the device can be equipped with a corresponding interface, such as a touch screen, via which the user can enter, for example, the model number of the grounding device.

[0026] According to a further embodiment, the grounding device data comprises one or more of the following parameters: type of grounding device, length of the grounding device, diameter of the grounding device, and / or material of the grounding device.

[0027] It has been found that the resistance between the poles determined by the device depends on the type and design of the grounding device. For example, whether the grounding device is a drive-in type, a screw-in type, or even a grounding belt is important. The length and diameter of the grounding device that can be lowered into the ground can also affect the resistance. Therefore, it is generally expected that the deeper the grounding device is inserted into the ground, the lower the resulting resistance value. Therefore, the control device of the present disclosure can be configured to adjust the first threshold value downward when a longer grounding device is used.

[0028] According to a further embodiment, the reference probe 208 and the grounding fixture 102 are made of materials that are close to each other in the galvanic voltage series, so that the resulting galvanic voltage does not exceed the maximum percentage of the measurement voltage applied to the pole by the device 202, depending on the application. In other words, according to this embodiment, the materials are selected so that the galvanic voltage is always less than the measurement voltage. The maximum percentage of the applied measurement voltage that is acceptable for the galvanic voltage depends on the application. For example, the galvanic voltage should not exceed 40% of the measurement voltage for electrostatic inductive discharges. For discharges of low-resistance components (e.g., 10 Ω), the galvanic voltage should not exceed 10% of the measurement voltage.

[0029] According to a further aspect, the present disclosure relates to a mobile grounding system comprising one of the above-mentioned devices for monitoring a mobile grounding device, a grounding device connected or connectable to a first pole of the device, and a reference probe connected or connectable to a second pole of the device.

[0030] According to a further aspect, the present disclosure relates to a method for monitoring a mobile grounding device, the method including inserting the mobile grounding device, particularly a ground rod, into the ground; inserting a reference probe, particularly a ground rod, into the ground; measuring an electrical resistance between the mobile grounding device and the reference probe; comparing the electrical resistance to a threshold; and outputting a status signal based on the comparison between the electrical resistance and the threshold.

[0031] According to a further embodiment, the earthing device is at a distance of at least 0.5 m from the reference probe. It has been found that a minimum distance of 0.5 m allows the control unit to detect resistance values ​​particularly reliably.

[0032] FIG. 1 illustrates a grounding device 100 for grounding mobile devices and charge carriers. A mobile grounding device 100 known in the prior art essentially includes a ground rod 102, which a user first rotates and inserts into the ground 104 before each use. The ground rod 102 includes an elongated portion 106 that can be inserted into the ground 104 and, subsequently, into the earth 108 below. To this end, the elongated portion 106 can be driven or screwed into the earth 108. However, it should be noted that the present disclosure is not limited in this regard with respect to the type of mobile grounding device. Rather, in addition to the ground rod shown here, other grounding devices, such as ground belts, can also be used. In either case, these grounding devices serve to connect the mobile terminal device or charge carrier to the earth 108.

[0033] In addition to the elongated portion 106, the grounding rod 102 shown in FIG. 1 by way of example has an interface region 110 that is inserted into the ground 108. The interface region 110 serves, among other things, to connect devices or charge carriers to be grounded. For example, in FIG. 1, the mobile grounding device has two ports 112, 114. The first port 112 is connected to a first object / device 116 to be discharged, and the second port 114 is connected to a second device 118 to be grounded. In this way, the mobile grounding device 102 can be used to ground a variety of surfaces / devices.

[0034] The electrical connection between the elongated portion 106 of the grounding device 102 and the ground 108 is usually not completely resistance-free. Rather, there is always some leakage resistance 120 between the mobile grounding device 102 and the ground 108. This is shown diagrammatically in FIG. 1 . The leakage resistance depends on several factors. For example, on the one hand, the nature of the ground 108 and, on the other hand, the characteristics of the mobile grounding device 102 are important. In particular, the insertion depth of the mobile grounding device 102 can play a major role. It has also been found that the diameter of the elongated portion 106 inserted into the ground 108 also affects the leakage resistance 120.

[0035] Typically, the leakage resistance 120 should be as low as possible to achieve reliable grounding of the surface / equipment in question. However, with mobile grounding devices known from the prior art, one often simply has to trust that the leakage resistance 120 is low enough to ensure reliable grounding. However, this can cause problems, especially with dry substrates such as gravel.

[0036] The present disclosure relates to an apparatus for monitoring a mobile grounding device, which is shown schematically in Figure 2. In particular, the apparatus according to the present disclosure can be used for permanent, i.e., continuous or periodic, monitoring of grounding quality. In particular, Figure 2 provides a schematic diagram of a system consisting of a mobile grounding device and an apparatus for monitoring the mobile grounding device. The system 200 shown in Figure 2 comprises a grounding device 102, which in this example is identical to the grounding device already shown in Figure 1.

[0037] The device 202 for monitoring the grounding device 102 comprises a first pole 204 electrically connectable to the mobile grounding device 102. The first pole 104 is particularly connected to the interface region 110 of the grounding device 102. In other words, the device 202 is connected to the earth 108 via the grounding device 102.

[0038] The device 202 further includes a second pole 206 connected to the earth 108 at a location spaced apart from the mobile grounding device 102. In the exemplary embodiment shown, the system includes a reference probe 208 inserted into the ground 106 at a distance from the mobile grounding device and thereby electrically connected to the earth 108. The reference probe 208 could also be, for example, a ground rod. However, in FIG. 2 , the reference probe 208 is shown slightly differently to emphasize the differences between the mobile grounding device 102 and the reference probe 208. It should be noted, however, that the reference probe 208 simply serves to connect the second pole 206 to the earth 108. Although technically equivalent and therefore conceivable, grounding via the reference probe 208 is preferably not performed. In other words, in an advantageous embodiment, the reference probe 208 has only one port 210 configured to electrically connect the reference probe 208 to the device 202 for monitoring the grounding device 102.

[0039] The reference probe 208 is preferably driven into the ground 108 to a depth similar to that of the portable grounding device 102. It should be noted that the measured resistance generally corresponds to the "poorer" leakage resistance between the reference probe 208 and the grounding device 102. Therefore, if the resistance generated by the reference probe 208 is significantly greater than that of the grounding device 102, the measurement results, and therefore the status signal, will be distorted. This is because the grounding device may be adequately grounded, but it is possible that only the reference probe 208, which is provided for monitoring purposes, is improperly connected to the ground. In this case, the control device (device) may output a warning signal, but the leakage resistance through the grounding device 102 is generally acceptable, i.e., below the required threshold. For the above reasons, the reference probe 208 is preferably driven into the ground 108 at a depth comparable to or greater than that of the grounding device's ground rod. To this end, the grounding fixture 102 and the reference probe 208 may be provided with corresponding markings to ensure that the reference probe 108 and the grounding fixture are driven / screwed to a sufficient depth into the ground.

[0040] Preferably, reference probe 208 is spaced at least 0.5 m from grounding fixture 102. Accordingly, system 200 may include a device (not shown) for spacing grounding fixture 102 away from reference probe 208. For example, this device may be a flexible plastic sheet (e.g., made from a composite material like a ski) that not only spaces reference probe 208 away from grounding fixture 102, but also insulates them from each other.

[0041] The apparatus 202 for monitoring the mobile grounding device 102 comprises a control device for detecting the electrical resistance between a first pole 204 and a second pole 206. In the illustrated embodiment according to FIG. 2, the resistance between the two poles 204, 206 of the apparatus 202 corresponds to the total resistance of the circuit formed by the mobile grounding device 102, the earth 108, and the reference probe 208. Because the mobile grounding device and the reference probe are made of metal, their electrical resistance to the earth is negligible. In other words, in the embodiment according to FIG. 2, the apparatus 202 only recognizes the resistance 212 of the earth 108 between the mobile grounding device 102 and the reference probe 208.

[0042] The present disclosure is based on the finding that the resistance 212 between the mobile grounding device 102 and the reference probe 208 substantially corresponds to the leakage resistance 120. Therefore, based on the resistance 212 between the mobile grounding device 102 and the reference probe 208, through the mobile grounding device 120, conclusions can be drawn about the leakage resistance 120 and therefore about the reliability of the ground.

[0043] The control device 202 for monitoring the portable grounding device 102 is configured to compare the electrical resistance between the two poles 204, 206 with a threshold value (not shown). If the electrical resistance exceeds the threshold value, the control device generates a warning signal that can be used to activate corresponding warning means, for example, optical and / or audible feedback. The threshold value can be set / adjusted for various applications. Thus, to achieve a sufficient protective ground (e.g., less than 10 Ω), a much lower leakage resistance is typically required than that required for the elimination of surface charges (e.g., less than 10 kΩ). Therefore, the control device can be configured to change the threshold value based on user information related to a specific application case (application data). The user information can be entered via a corresponding interface, such as a touchscreen. The control device can be configured to prompt the user to indicate the application case (e.g., via a drop-down menu) upon power-up.

[0044] In an exemplary embodiment, the status signal can be output to the user by lighting a status lamp. Alternatively or additionally, an audible warning can be output by the device for monitoring the portable grounding device. In a normal state, for example, if the resistance between the two poles is below a threshold, positive feedback can be output, for example, by a green light. The green status light remains displayed as long as the resistance between the two poles 204, 206 is below the threshold. The status signal output by the control device is used to switch the green status indicator off only if the threshold is exceeded. According to this embodiment, the user receives feedback even during insertion when a sufficient ground is achieved, i.e., when the device 202 outputs a positive status signal (e.g., a green light).

[0045] The present disclosure is not limited to the embodiments shown in the figures, but rather results from all combinations of features disclosed in this application.

Claims

1. A device (202) for monitoring a mobile grounding device (102), comprising: a first pole (204) for connection to the portable grounding device (102); a second pole (206) for connection to a reference probe (208); A control device comprising: sensing an electrical resistance between the first pole (204) and the second pole (206); comparing the electrical resistance to a threshold value; outputting a status signal based on a comparison between the electrical resistance and the threshold value; a control device configured for the purpose of An apparatus (202) comprising:

2. The apparatus (202) of claim 1, wherein the control device is configured to sense the electrical resistance between the first pole (204) and the second pole (206) continuously or at regular intervals.

3. 3. The device (202) according to claim 1 or 2, wherein the device (202) comprises means for optically and / or acoustically outputting the status signal.

4. The apparatus (202) of any one of claims 1 to 3, wherein the control device is configured to output a grounding success signal as a status signal when the electrical resistance is less than the threshold value, and / or the control device is configured to output a warning signal as a status signal when the electrical resistance exceeds the threshold value.

5. The control device receiving usage data indicative of a usage of the portable grounding device; setting the threshold value based on the usage data; The apparatus (202) of any one of claims 1 to 4, configured to:

6. 6. The apparatus (202) of claim 1, wherein the apparatus (202) is battery-powered or connectable to an external power source, and / or the control device is configured to apply an intrinsically safe voltage to a pole for detecting the resistance.

7. The apparatus (202) according to any one of claims 1 to 6, comprising a control terminal connectable to an equipment to be grounded, and the control device is configured to output a release signal to the control terminal when the electrical resistance is less than the threshold value, and / or to output an emergency stop signal to the control terminal when the electrical resistance exceeds the threshold value.

8. The control device receiving grounding device data indicative of a grounding device to be used; setting the threshold value based on the grounding device data; The apparatus (202) of any one of claims 1 to 7, configured to:

9. The grounding device data includes the following parameters: The type of the grounding device (102), the length of the grounding device (102); the diameter of the grounding device (102), or the material of the grounding device (102); The apparatus (202) of claim 8, comprising one or more of:

10. 1. A mobile grounding system comprising: An apparatus (202) according to any one of claims 1 to 9; a grounding device (102) connected or connectable to the first pole (204) of the device (202); a reference probe (208) connected or connectable to the second pole (206) of the device (202); A mobile grounding system comprising:

11. 11. The mobile grounding system of claim 10, wherein the grounding system comprises a device for moving the reference probe (208) away from the grounding fixture (102), the device being configured to position the reference probe (208) at a distance of at least 0.5 m from the grounding fixture (102).

12. 12. The mobile grounding system of claim 10 or 11, wherein the reference probe (208) and the grounding fixture (102) are made of materials that are close to each other in a galvanic voltage series, so that the generated galvanic voltage does not exceed a maximum percentage of the measured voltage applied to the pole by the device (202), the maximum percentage being application dependent.

13. 1. A method for monitoring a mobile grounding device, comprising: Inserting a mobile grounding device (102), in particular a ground rod, into the ground; Inserting a reference probe (208), in particular a ground rod, into the ground; measuring the electrical resistance between the portable grounding device (102) and the reference probe (208); comparing the electrical resistance to a threshold value; outputting a status signal based on a comparison between the electrical resistance and the threshold value; A method comprising:

14. The method of claim 13, wherein the grounding fixture (102) is spaced at least 0.5 m from the reference probe (208).

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