CN109782039B - Current measurement method, current measurement device and current signal measurement system - Google Patents

Current measurement method, current measurement device and current signal measurement system Download PDF

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CN109782039B
CN109782039B CN201910206365.2A CN201910206365A CN109782039B CN 109782039 B CN109782039 B CN 109782039B CN 201910206365 A CN201910206365 A CN 201910206365A CN 109782039 B CN109782039 B CN 109782039B
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probe
data
range data
analog voltage
voltage signal
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CN109782039A (en
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洪少林
杨志凌
钟泓
陈敬奉
蔡伟明
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Uni Trend Technology China Co Ltd
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Uni Trend Technology China Co Ltd
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Abstract

The invention relates to an automatic probe signal identification method, which comprises the following steps: reading the gear level of the probe; acquiring range data of the probe corresponding to the gear level; and controlling the probe to output a corresponding analog voltage signal according to the range data, and sending the range data and the analog voltage signal to a reading device. The method adopted by the invention can ensure that the universal meter or the clamp meter does not need to set the functional gear and the measuring range gear any more, directly and automatically identify the measuring range data of the external current probe and ensure the correct measurement data.

Description

Current measurement method, current measurement device and current signal measurement system
Technical Field
The invention belongs to the field of current measurement, and particularly relates to a method, equipment and a system for automatically identifying a probe signal and a probe.
Background
Currently, the maximum current that can be measured by a conventional universal meter on the market is 20A, and the maximum current that can be measured by a clamp meter is 1000A. In order to meet the measurement requirement of larger current, the universal meter and the clamp meter can be used for measuring through an external current probe, so that the measurable current range of the universal meter and the clamp meter is enlarged to be within 3000A, and the universal meter and the clamp meter are suitable for wider measurement scenes. In order to obtain accurate measurement data, the current probe is generally provided with three gears according to the required measurement current to represent different measuring ranges of 30A/300A/3000A, and the three measuring ranges can respectively and correspondingly output three voltage signals of 100mV/A,10mV/A and 1 mV/A.
The universal meter or the clamp meter connected with the current probe is also provided with three different measuring range gears which are used for matching the measuring range of the current probe during measurement, so that no error of measured data is realized. However, the range gear on the multimeter cannot be automatically identified, and when the multimeter is used, a user firstly judges and then manually selects the range which is required to be matched by the universal meter or the clamp meter according to the range gear set by the external current probe. The process is more complicated when multiple measurements are required. If the measuring range on the universal meter or the clamp meter is set wrong, the measured current can cause misjudgment, the accuracy of the measured data is affected, and if the universal meter or the clamp meter is set wrong when the 3000A current is measured by the external current probe, 30A or 300A is correspondingly displayed. Therefore, the measurement mode is complicated and professional, accurate measurement data cannot be obtained if the matching is wrong, and great trouble is brought to the measurement or experimental process.
Disclosure of Invention
Aiming at the problems, the invention aims to provide a probe signal automatic identification method, equipment, a system and a probe, which can automatically identify the range data of an external current probe and ensure that measurement data is correctly acquired.
In order to achieve the above purpose, the present invention adopts the following technical scheme:
A current measurement method comprising a probe and a reading device, the probe being provided separately from the reading device, comprising: reading the gear level of the probe; acquiring range data of the probe corresponding to the gear level;
controlling the probe to output a corresponding analog voltage signal according to the range data, and sending the range data and the analog voltage signal to a reading device;
the range data includes at least: a data header, span data, and a checksum;
The method further comprises: acquiring measurement data through a probe induction coil, and controlling the amplification factor of the measurement data according to the range data so as to output the corresponding analog voltage signal; further comprises: acquiring range data and analog voltage signals output by a probe;
Adjusting the measuring range according to the measuring range data, and performing digital-to-analog conversion on the analog voltage signal to obtain measuring data; the range data includes at least: a data header, span data, and a checksum;
the method further comprises the steps of: and receiving the range data output by the probe through an infrared receiving device.
A current measurement apparatus comprising a probe and a reading device, the probe being provided separately from the reading device, comprising: the device comprises a first receiving unit and a second receiving unit, wherein the first receiving unit is used for acquiring range data output by a probe, and the second receiving unit is used for acquiring an analog voltage signal output by the probe; the first processing unit is used for acquiring range data from the first receiving unit and adjusting the range of the equipment according to the range data;
The analog-to-digital conversion unit is used for performing digital-to-analog conversion on the analog voltage signal to obtain measurement data; the first processing unit further includes: the first universal asynchronous receiving and transmitting unit is used for continuously receiving the range data acquired by the first receiving unit;
the probe includes: the third receiving unit is used for reading the gear level of the probe;
The fourth receiving unit is used for acquiring range data of the probe corresponding to the gear level; the second processing unit is used for controlling the probe to output a corresponding analog voltage signal according to the range data; the first sending unit is used for sending the range data to the reading equipment; a second transmitting unit for transmitting the analog voltage signal to a reading device;
The range data includes at least: data header, span data, and checksum.
In the above current measurement device, preferably, the first receiving unit is an infrared receiving tube.
The current measuring apparatus preferably includes: and the signal amplifying circuit is used for controlling the amplification factor of the measurement data according to the range data so as to output the corresponding analog voltage signal.
A current signal measurement system comprising the current measurement device of any one of the above.
The current measuring method, the current measuring device and the current signal measuring system can accurately and automatically identify the range data and the voltage signal of the external probe signal, and ensure the accuracy of data measurement without the modes of manual judgment and manual adjustment.
Drawings
FIG. 1 is a schematic diagram of a probe signal automatic identification device according to an embodiment of the present invention;
FIG. 2 is a schematic view of a probe according to an embodiment of the present invention;
Fig. 3 is a schematic structural diagram of an automatic probe signal recognition system according to an embodiment of the present invention.
Detailed Description
The present invention will be described in detail with reference to the accompanying drawings and examples.
The embodiment of the invention provides a probe signal automatic identification method, which comprises the following steps: reading the gear level of the probe; acquiring range data of the probe corresponding to the gear level;
and controlling the probe to output a corresponding analog voltage signal according to the range data, and sending the range data and the analog voltage signal to a reading device.
In a specific embodiment, the probe has three gear positions 30A, 300A,3000A, respectively. Different gear levels correspond to different gear levels, and the gear levels consist of three binary codes K1, K2 and K3. The user manually fluctuates the gear to any gear of 30A, 300A and 3000A, and a gear level corresponding to the shifted gear is formed inside the probe. Therefore, the gear level is read through the GPIO port, and the corresponding gear can be judged.
In the embodiment of the present invention, as shown in table one, when the gear levels K1, K2, K3 of the probe read are 011, the corresponding gear is 30A; when the gear levels K1, K2 and K3 of the read probe are 101, the corresponding gear is 300A; when the gear levels K1, K2 and K3 of the read probe are 110, the corresponding gear is 3000A. The gear level of the probe and the gear form a one-to-one correspondence, so that the gear level of the probe can be obtained to judge which gear the probe is shifted to during measurement.
Table I gear and gear level comparison table
And acquiring range data of the probe corresponding to the gear level, wherein the range data and the gear level have a one-to-one correspondence. Preferably, the range data at least includes: data header, range and checksum, as shown in table two. When the gear is shifted to 30A, the gear level is 011, and the range data is aa0x300xda.
Table II gear level and range data comparison table
And controlling the probe to output a corresponding analog voltage signal according to the range data, and sending the range data and the analog voltage signal to a reading device. Preferably, the reading device may be a multimeter or a clamp meter.
The method for automatically identifying the probe signal according to the embodiment of the invention preferably further comprises the following steps: and acquiring measurement data through a probe induction coil, and controlling the amplification factor of the measurement data according to the range data so as to output the corresponding analog voltage signal. Specifically, the current value of the measured object is firstly obtained through the probe induction coil to serve as measurement data, then the amplification factor of the collected measurement data is controlled according to the measurement range data obtained in the previous step, and finally an amplified analog voltage signal is obtained to be beneficial to subsequent output. Specifically, three voltage signals of different magnitudes of 100mV/A, 10mV/A and 1mV/A are respectively output according to the gear 30A/300A/3000A as amplification factors, and the measured current value is amplified to finally output a required analog voltage signal.
In a preferred embodiment of the invention, the range data and the analog voltage signal are sent to the reading device by different output modes. Specifically, the analog voltage signal is transmitted to the reading device in a wired transmission manner. The range data is transmitted to the reading equipment in an infrared transmission mode, so that the cost is saved, the complexity in a wire distribution structure caused by a wired transmission mode is avoided, and the output is unstable due to the fact that the analog voltage signal of the wireless frequency interference probe is output in other wireless transmission modes, so that the normal reading of the reading equipment is affected.
In a preferred embodiment, after the span data is obtained, the span data is sent to an infrared transmitting device located on the probe through UART (universal asynchronous receiver transmitter) interrupt.
According to the embodiment, the range data and the voltage signal of the external probe signal can be accurately and automatically identified, and the accuracy of data measurement is ensured without the mode of manual judgment and manual adjustment.
Another embodiment of the present invention provides a method for automatically identifying a probe signal, including: acquiring range data and analog voltage signals output by a probe; preferably, since the analog voltage signal is transmitted in the form of an electrical signal, the analog voltage signal can be directly received by a wired transmission manner. The range data is transmitted by an infrared communication mode, so that the range data is received by an infrared receiving device, and then the range data transmitted by the infrared receiving device is received by UART (universal asynchronous receiver transmitter).
Preferably, the infrared receiving device is an infrared receiving tube. The infrared receiving device is adopted to realize the advantages of automatic data transmission, no interference and high speed.
And adjusting the measuring ranges of the universal meter and the clamp meter according to the measuring range data, and performing digital-to-analog conversion on the analog voltage signal when the equivalent range is positioned at a correct gear so as to obtain accurate measurement data. Before obtaining the measurement data, the measurement range is adjusted to prevent a read error when the analog voltage signal is read later.
In a preferred embodiment, when the external current probe is not connected, the multimeter or the clamp meter displays an internal current measurement interface, and when the range data and the analog voltage signal output by the probe are read, the internal current measurement interface is automatically converted into the external current probe interface, and meanwhile, the corresponding range data is automatically displayed without manual adjustment.
The embodiment of the invention also provides automatic probe signal identification equipment, as shown in fig. 1, comprising:
A first receiving unit 10 and a second receiving unit 11, wherein the first receiving unit 10 is used for acquiring range data output by a probe, and the second receiving unit 11 is used for acquiring an analog voltage signal output by the probe; preferably, since the analog voltage signal is transmitted in a wired transmission manner, the second receiving unit corresponds to a wired receiving device. The measurement data are transmitted by means of an infrared transmitting device, so that the first receiving unit is an infrared receiving device. Preferably, the infrared receiving device is an infrared receiving tube. The infrared receiving device has the advantages of automation, no interference and high speed, and meanwhile, the complexity of a wire distribution structure caused by a wire transmission mode is avoided, and the output instability is caused by the output of analog voltage signals of a wireless frequency interference probe in other wireless transmission modes, so that the reading of the equipment is influenced.
A first processing unit 12, configured to obtain range data from the first receiving unit 10 and adjust a range of the device according to the range data; and adjusting the range of the equipment to a correct gear according to the received range data so as to prevent errors in data reading.
An analog-to-digital conversion unit 13 for performing analog-to-digital conversion on the analog voltage signal to obtain measurement data. Specifically, when the equivalent range outputs the correct gear, the analog-to-digital conversion unit 13 performs analog-to-digital conversion on the analog voltage signal to obtain accurate measurement data.
Preferably, the device further comprises a verification unit, wherein the verification unit is used for verifying the accuracy of the range data through the received analog voltage signal, when the verification is correct, the first processing unit adjusts the range of the device to the correct gear, and when the verification is incorrect, the first processing unit sends out a warning.
In a preferred embodiment, the apparatus further comprises a display unit 14, wherein when the external current probe is not connected, the display unit displays the internal current measurement interface, and when the range data and the analog voltage signal output by the probe are read, the display unit 14 automatically converts the range data into the external current probe interface, and simultaneously automatically displays the corresponding range data without manual adjustment.
In the probe signal automatic identification device according to the embodiment of the present invention, preferably, the first processing unit 12 further includes:
and the first universal asynchronous receiving and transmitting unit interrupts receiving the range data acquired by the first receiving unit 10. And the first Universal Asynchronous Receiver Transmitter (UART) is used for receiving the range data of the serial port provided by the infrared receiving device in an interruption way, so that the rapid and accurate transmission of the range data is realized.
The embodiment of the invention also provides a probe, as shown in fig. 2, comprising: a third receiving unit 20 for reading the gear level of the probe;
A fourth receiving unit 21, configured to acquire range data of the probe corresponding to the gear level; the second processing unit 22 is configured to control the probe to output a corresponding analog voltage signal according to the range data; a first transmitting unit 23 for transmitting the range data to a reading device;
a second transmitting unit 24 for transmitting the analog voltage signal to the reading device.
Specifically, the third receiving unit 20 reads the gear level of the probe and transmits the gear level to the fourth receiving unit 21 to acquire range data of the probe corresponding to the gear level. And then sent to the second processing unit 22, and the second processing unit 22 controls the probe to output a corresponding analog voltage signal according to the range data. The analog voltage signal is sent to the second sending unit 24 for sending to the reading device and the span data is sent to the first sending unit 23 for providing to the reading device.
Preferably, the probe further comprises a gear switch for adjusting the probe to output different voltage signals. The gear switch has three gears 30A, 300A and 3000A respectively. Different gear levels correspond to different gear levels, and the gear levels consist of three binary codes K1, K2 and K3. The user manually fluctuates the gear switch to any gear of 30A, 300A and 3000A, and a gear level corresponding to the shifted range data is formed inside the probe. The gear level is thus read by the third receiving unit.
In the embodiment of the present invention, as shown in table one, when the gear levels K1, K2, K3 of the probe read are 011, the corresponding gear is 30A; when the gear levels K1, K2 and K3 of the read probe are 101, the corresponding gear is 300A; when the gear levels K1, K2 and K3 of the read probe are 110, the corresponding gear is 3000A. The gear level of the probe and the gear switch form a one-to-one correspondence, so that the gear level of the probe can be obtained to further know which gear switch the probe is positioned on. And acquiring range data of the probe corresponding to the gear level, wherein the range data and the gear level have a one-to-one correspondence. Preferably, the range data at least includes: the data header, the range data and the checksum are specifically shown in the second reference table. When the gear is shifted to 30A, the gear level is 011, and the range data is aa0x300xda.
In a preferred embodiment of the present invention, the probe further comprises: and the signal amplifying circuit is used for controlling the amplification factor of the measurement data according to the range data so as to output the corresponding analog voltage signal. According to different gear levels, the signal amplifying circuit can also respectively output three voltage signals with different magnitudes of 100mV/A, 10mV/A and 1mV/A as amplification multiples to amplify the measured current value so as to finally output the required analog voltage signal.
In a preferred embodiment of the present invention, the first transmitting unit is an infrared transmitting device. Specifically, the range data is transmitted to the reading equipment through the infrared transmitting device, so that the cost is saved, the complexity of a wire distribution structure caused by a wired transmission mode is avoided, and the output instability caused by the output of an analog voltage signal of a wireless frequency interference probe in other wireless transmission modes is avoided, so that the normal reading of the reading equipment is influenced. Preferably, the reading device may be a multimeter or a clamp meter.
Preferably, the infrared transmitting device is an infrared transmitter. The infrared transmitting device has the advantages of automation, no interference and high speed.
Preferably, the probe further comprises a probe induction coil for acquiring measurement data, and the measurement data is sent to a signal amplifying circuit for subsequent processing by the signal amplifying circuit.
Preferably, the second processing unit further includes a second general asynchronous receiving and transmitting unit, configured to interrupt sending of the corresponding range data to the first sending unit.
The embodiment of the invention also provides an automatic probe signal identification system, as shown in fig. 3, which comprises the automatic probe signal identification device 30 and the probe 31 according to any of the above embodiments. The probe is provided with an infrared transmitting device, and the probe signal automatic identification equipment is provided with an infrared receiving device to realize infrared receiving and transmitting of data.
In summary, the method, the device, the system and the probe for automatically identifying the probe signals disclosed by the embodiment of the invention enable the universal meter or the clamp meter to directly and automatically identify the range data of the external current probe without setting a functional gear and a range gear, thereby ensuring correct measurement data.
The present application is not limited to the above-mentioned preferred embodiments, and any person can obtain various other products without departing from the scope of the present application, but any changes in shape or structure are within the scope of the present application, regardless of the technical scheme which is the same as or similar to the present application.

Claims (5)

1. A current measurement method comprising a probe and a reading device, wherein the probe is provided separately from the reading device, comprising:
Reading the gear level of the probe;
Acquiring range data of the probe corresponding to the gear level;
controlling the probe to output a corresponding analog voltage signal according to the range data, and sending the range data and the analog voltage signal to a reading device;
the range data includes at least: a data header, span data, and a checksum;
the method further comprises: acquiring measurement data through a probe induction coil, and controlling the amplification factor of the measurement data according to the range data so as to output the corresponding analog voltage signal;
Further comprises:
acquiring range data and analog voltage signals output by a probe;
adjusting the measuring range according to the measuring range data, and performing digital-to-analog conversion on the analog voltage signal to obtain measuring data;
the range data includes at least: a data header, span data, and a checksum;
the method further comprises the steps of:
And receiving the range data output by the probe through an infrared receiving device.
2. A current measurement apparatus comprising a probe and a reading device, wherein the probe is provided separately from the reading device, comprising:
The device comprises a first receiving unit and a second receiving unit, wherein the first receiving unit is used for acquiring range data output by a probe, and the second receiving unit is used for acquiring an analog voltage signal output by the probe;
The first processing unit is used for acquiring range data from the first receiving unit and adjusting the range of the equipment according to the range data;
The analog-to-digital conversion unit is used for performing digital-to-analog conversion on the analog voltage signal to obtain measurement data;
the first processing unit further includes: the first universal asynchronous receiving and transmitting unit interrupts receiving of the range data acquired by the first receiving unit;
The probe includes:
the third receiving unit is used for reading the gear level of the probe;
The fourth receiving unit is used for acquiring range data of the probe corresponding to the gear level;
The second processing unit is used for controlling the probe to output a corresponding analog voltage signal according to the range data;
the first sending unit is used for sending the range data to the reading equipment;
A second transmitting unit for transmitting the analog voltage signal to a reading device;
The range data includes at least: data header, span data, and checksum.
3. The current measurement device of claim 2, wherein the first receiving unit is an infrared receiving tube.
4. The current measurement device according to claim 2, comprising: and the signal amplifying circuit is used for controlling the amplification factor of the measurement data according to the range data so as to output the corresponding analog voltage signal.
5. A current signal measuring system comprising a current measuring device according to any one of claims 2-4.
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