CN117007209A - Multichannel detection device suitable for transmitter and flow computer - Google Patents
Multichannel detection device suitable for transmitter and flow computer Download PDFInfo
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- CN117007209A CN117007209A CN202210453781.4A CN202210453781A CN117007209A CN 117007209 A CN117007209 A CN 117007209A CN 202210453781 A CN202210453781 A CN 202210453781A CN 117007209 A CN117007209 A CN 117007209A
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- 238000001514 detection method Methods 0.000 title claims abstract description 64
- 238000006243 chemical reaction Methods 0.000 claims abstract description 57
- 238000002955 isolation Methods 0.000 claims description 8
- 238000012937 correction Methods 0.000 abstract description 2
- 230000010354 integration Effects 0.000 abstract 1
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 6
- 238000010586 diagram Methods 0.000 description 5
- 229910052697 platinum Inorganic materials 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000008054 signal transmission Effects 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000012795 verification Methods 0.000 description 1
Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K15/00—Testing or calibrating of thermometers
- G01K15/005—Calibration
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L25/00—Testing or calibrating of apparatus for measuring force, torque, work, mechanical power, or mechanical efficiency
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L27/00—Testing or calibrating of apparatus for measuring fluid pressure
- G01L27/002—Calibrating, i.e. establishing true relation between transducer output value and value to be measured, zeroing, linearising or span error determination
- G01L27/005—Apparatus for calibrating pressure sensors
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- Analytical Chemistry (AREA)
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Abstract
The invention relates to the field of equipment detection and correction, in particular to a multichannel detection device suitable for a transmitter and a flow computer. According to the invention, through arranging the change-over switch and the plurality of detection channels, a plurality of devices are detected at one time, so that the detection efficiency is improved, and the use frequency of the standard device and the pressure pump is reduced; and through the combination of the current/voltage conversion circuit and the thermal resistance value conversion circuit, the integration of the detection of the pressure transmitter or the temperature transmitter which outputs standard current into one device is realized, thereby effectively increasing the universality of the invention.
Description
Technical Field
The invention relates to the field of equipment detection and correction, in particular to a multichannel detection device suitable for a transmitter and a flow computer.
Background
Because of the continuous and deep construction of the informationized gas field, a large number of current output type pressure transmitters and temperature transmitters are required to be regularly calibrated. In the metering detection process, the traditional detection method can only detect 1 pressure transmitter at a time, calibrate 1 temperature transmitter at a time or detect 1 signal channel of a flow rate computer at a time.
The traditional detection method and the existing standard appliance configuration are difficult for detection personnel to meet the detection requirement of a large number of measuring instruments, so that the current situation that a large number of pressure transmitters and temperature transmitters run out of date is caused. Therefore, it is needed to reduce the repeated pressurization (adding 1 time of voltage to detect multiple current output type pressure transmitters with the same measuring range), reduce the resistance of the repeated rotation direct current resistor (rotating 1 time of the resistance of the direct current resistor to detect multiple current output type temperature transmitters with the same measuring range or the temperature transmitter of the flow integrating instrument), and realize the capability of simultaneously detecting multiple voltage changes, temperature changes and flow computer signal channels at one time so as to avoid the condition that the pressure transmitters and the temperature transmitters run out of time due to untimely detection.
Disclosure of Invention
The invention aims to solve the problems that only one device can be detected at a time and all detection devices cannot be integrated in the prior art, and provides a multichannel detection device suitable for a transmitter and a flow computer.
In order to achieve the above object, the present invention provides the following technical solutions:
the multichannel detection device suitable for the transmitter and the flow computer comprises a detection module and an alternating current/direct current conversion circuit which are electrically connected with each other, wherein the detection module comprises a change-over switch and a plurality of detection units electrically connected with the change-over switch;
the detection unit comprises a current/voltage conversion circuit, a thermal resistance value conversion circuit, a first wire connector and a second wire connector;
the current/voltage conversion circuit and the thermal resistance value conversion circuit are electrically connected with each other; the first connector is electrically connected with the current/voltage conversion circuit and is used for externally connecting a current source; the second connector is electrically connected with the thermal resistance value conversion circuit and is used for externally connecting a direct current resistor;
the change-over switch is used for switching the detection unit connected with the change-over switch. According to the invention, through arranging the change-over switch and the plurality of detection channels, a plurality of devices are detected at one time, so that the detection efficiency is improved, and the use frequency of the standard device and the pressure pump is reduced; and by combining the current/voltage conversion circuit and the thermal resistance value conversion circuit, the detection of the pressure transmitter or the temperature transmitter which outputs standard current is integrated into one device, so that the universality of the invention is effectively improved.
As a preferred scheme of the invention, the first connector comprises 3 connection ports, and the current/voltage conversion circuit comprises a relay switch and positive and negative detection ports for connecting a transmitter to be detected;
the port 1 of the first connector is electrically connected with the change-over switch;
the driving coil of the relay switch is electrically connected with the change-over switch, two ends of a contact of the relay switch are respectively electrically connected with a No. 2 port and a positive detection port of the first connector, and a negative detection port is electrically connected with a No. 3 port of the first connector.
As a preferable scheme of the invention, a protection circuit is arranged between the ac/dc conversion circuit and the port No. 1 of the first connector.
As a preferable scheme of the invention, the protection circuit comprises a current limiting resistor and a reverse diode which are electrically connected in sequence.
As a preferred embodiment of the present invention, the first connector further includes a spare port. The spare port is used for carrying out emergency substitution when the ports 1-3 fail.
As a preferable scheme of the invention, the relay switch is a photoelectric isolation relay.
As a preferable mode of the present invention, the second connector includes n connection ports, the thermal resistance value conversion circuit includes n relay switches and a resistance port for connecting a thermal resistor, n is an integer greater than 1;
the driving coil of the ith relay switch is electrically connected with the current/voltage conversion circuit corresponding to the detection unit, and two ends of a contact of the relay switch are respectively electrically connected with an i-number port and a resistance port of the second connector, i epsilon [1, n ].
As a preferable scheme of the invention, the relay switch is a photoelectric isolation relay.
As a preferred embodiment of the present invention, the line resistance deviation of any two of the detection units is less than 5mΩ. The invention realizes the effect that the conversion precision of thermal resistance is less than or equal to +/-0.05 ℃ and the conversion precision of current/voltage is less than or equal to +/-0.01% FS through accurately setting the circuit, effectively improves the detection precision of the invention and reduces the measurement error.
Compared with the prior art, the invention has the beneficial effects that:
1. according to the invention, through arranging the change-over switch and the plurality of detection channels, a plurality of devices are detected at one time, so that the detection efficiency is improved, and the use frequency of the standard device and the pressure pump is reduced; and by combining the current/voltage conversion circuit and the thermal resistance value conversion circuit, the detection of the pressure transmitter or the temperature transmitter which outputs standard current is integrated into one device, so that the universality of the invention is effectively improved.
2. The invention realizes the effect that the conversion precision of thermal resistance is less than or equal to +/-0.05 ℃ and the conversion precision of current/voltage is less than or equal to +/-0.01% FS through accurately setting the circuit, effectively improves the detection precision of the invention and reduces the measurement error.
Drawings
FIG. 1 is a schematic diagram of a multi-channel detector for a transmitter and a flow computer according to embodiment 1 of the present invention;
FIG. 2 is an electrical schematic diagram of a multi-channel sensing device for a transmitter and a flow computer according to embodiment 3 of the present invention;
FIG. 3 is a schematic diagram of a multi-channel detector for a transmitter and a flow computer according to embodiment 3 of the present invention;
FIG. 4 is a schematic diagram of a multi-channel detector for a transmitter and a flow computer according to embodiment 3 of the present invention, wherein the multi-channel detector uses a ConsT811 constant current source to detect a pressure signal of a QJG02-X flow computer;
fig. 5 is a channel wiring diagram of a multichannel detecting device for a transmitter and a flow computer according to embodiment 3 of the present invention when detecting a temperature signal of a QJG02-X flow computer using a constt 811 constant current source.
Detailed Description
The present invention will be described in further detail with reference to test examples and specific embodiments. It should not be construed that the scope of the above subject matter of the present invention is limited to the following embodiments, and all techniques realized based on the present invention are within the scope of the present invention.
Example 1
As shown in FIG. 1, a multi-channel detection device suitable for a transmitter and a flow computer comprises a detection module and an AC/DC conversion circuit which are electrically connected with each other, wherein the detection module comprises a change-over switch and a plurality of detection units electrically connected with the change-over switch;
the detection unit comprises a current/voltage conversion circuit, a thermal resistance value conversion circuit, a first wire connector and a second wire connector;
the current/voltage conversion circuit and the thermal resistance value conversion circuit are electrically connected with each other; the first connector is electrically connected with the current/voltage conversion circuit and is used for externally connecting a current source; the second connector is electrically connected with the thermal resistance value conversion circuit and is used for externally connecting a direct current resistor;
the change-over switch is used for switching the detection unit connected with the change-over switch.
The first connector comprises 3 connection ports, and the current/voltage conversion circuit comprises a relay switch and a positive and negative detection port used for connecting a transmitter to be detected;
the port 1 of the first connector is electrically connected with the change-over switch;
the driving coil of the relay switch is electrically connected with the change-over switch, two ends of a contact of the relay switch are respectively electrically connected with a No. 2 port and a positive detection port of the first connector, and a negative detection port is electrically connected with a No. 3 port of the first connector.
The second connector comprises n connection ports, the thermal resistance value conversion circuit comprises n relay switches and a resistance port used for connecting a thermal resistor, and n is an integer larger than 1;
the driving coil of the ith relay switch is electrically connected with the current/voltage conversion circuit corresponding to the detection unit, and two ends of a contact of the relay switch are respectively electrically connected with an i-number port and a resistance port of the second connector, i epsilon [1, n ].
The relay switches in the current/voltage conversion circuit and the thermal resistance value conversion circuit are photoelectric isolation relays, and the line resistance deviation of any two detection units is smaller than 5mΩ.
Example 2
The difference between the present embodiment and embodiment 1 is that a protection circuit is disposed between the ac/dc conversion circuit and the port No. 1 of the first connector; the first switch also includes a backup port.
The protection circuit comprises a current limiting resistor and a reverse diode which are electrically connected in sequence. The spare port is used for carrying out emergency substitution when the ports 1-3 fail.
Example 3
As shown in fig. 2 and 3, this embodiment is a practical application example when the detection unit of the device described in embodiment 2 is 8 and n is 4. At this time, the change-over switch adopts a knob switch K1 with 8 gears. The following is an example of an actual detection application:
1. setting or calibrating of the transmitter (current type pressure transmitter or temperature transmitter) by the connecting manual operation device:
the 250 omega load resistor is connected to the signal input terminals (namely the first connector) 1 and 2 of the current/voltage conversion circuit 4, the signal wires of the manual operator are respectively connected to the two sides of the load resistor, the manual operator can be respectively connected with each path of transmitter through the change-over switch 2, and the state of the transmitter can be set and verified by using the manual operator.
2. Pressure transmitter detects:
(1) The precise ammeter is connected to the input 1 and 2 terminals of the current/voltage converter circuit 4 (the signal input 3 and 4 terminals of the current/voltage converter circuit 4 are not used), the thermal resistor converter circuit 3 is not operated, the signal output of the current/voltage converter circuit 4 is controlled by the change-over switch 2 (only the same signal output terminal consistent with the switch gear supplies power to the pressure transducer when the switch is switched once), and the ac/dc converter circuit 1 supplies 24VDC to the pressure transducer through the precise ammeter and the corresponding opto-electric isolation relay pull-in.
(2) If the transmitter to be detected is a pressure transmitter with HART protocol, the HART protocol of the ConsT822 intelligent pressure calibrator and the ConsT811 pressure calibrator can be utilized to be connected with the signal input 2 and 3 terminals of the current/voltage converter circuit 4 (the hart+ is connected with the signal input 2 terminal of the current/voltage converter circuit 4, the hart+ is connected with the signal input 3 terminal of the current/voltage converter circuit 4, the input signals 1 and 4 terminals of the current/voltage converter circuit 4 are idle), the signal output of the current/voltage converter circuit 4 is controlled through the change-over switch 2 (only the same signal output terminal consistent with the switch gear provides power for the pressure transmitter every time when the switch is changed), and the HART protocol of the pressure calibrator provides 24VDC for the transmitter through the attraction of the photoelectric isolation relay responding to the pressure transmitter, and the corresponding current output values of different pressures applied on the transmitter can be detected.
3. Temperature transmitter detects:
the output of the direct current resistor (ZX 74D direct current resistor is adopted in the embodiment) is connected with signal inputs (namely second connectors) PT1 to PT4 of the thermal resistance converter circuit 3, a power terminal of the 8-path temperature transmitter is connected with 8-path signal output terminals of the current/voltage conversion circuit 4, the platinum resistor of the temperature transmitter is taken down according to the connection condition of the platinum resistor of the temperature transmitter and the direct current resistor in combination with the connection condition of the PT1 to PT4, and the signal output 8-path terminals of the thermal resistance conversion circuit 3 replace the platinum resistor to be respectively connected with the 8-path temperature transmitter.
(1) The 24VDC output by the ac/dc conversion circuit 1 is used to provide 24VDC power to the temperature transmitter:
the precision ammeter is connected to the input 1 and 2 terminals of the current/voltage converter circuit 4 (the signal input 3 and 4 terminals of the current/voltage converter circuit 4 are not used), the signal output of the current/voltage converter circuit 4 is controlled through the change-over switch 2 (only the same signal output terminal consistent with the switch gear supplies power to the pressure transmitter when the switch is changed once), meanwhile, the 24VDC power supply supplies 24VDC power to the pressure transmitter through the precision ammeter and the corresponding photoelectric isolation relay attraction, and the current output value of the 8-channel temperature transmitter when the same standard resistor can be checked once by changing the resistance value of the direct current resistor and the gear of the change-over switch 2.
(2) If the temperature transmitter supports the HART protocol, the HART protocol of the pressure check instruments of constt 822 and constt 811 can be used to control the 8-way signal output of the current/voltage conversion circuit 4 (for providing 24VDC power for the temperature transmitter) through the conversion switch 2:
the HART protocol output terminal of the pressure calibrator is connected with the signal input 2 and 3 terminals of the current/voltage converter circuit 4 (hart+ is connected with the signal input 2 terminal of the current/voltage converter circuit 4, HART-is connected with the signal input 3 terminal of the current/voltage converter circuit 4, the input signals 1 and 4 terminals of the current/voltage converter circuit 4 are idle), the signal output of the current/voltage converter circuit 4 is controlled through the change-over switch 2 (only the same signal output terminal consistent with the switch gear supplies power to the pressure transmitter when the switch is changed once), and the HART protocol signal of the pressure calibrator supplies 24VDC to the transmitter through the pull-in of the corresponding photoelectric isolation relay, and the corresponding current output value of different standard resistors applied to the transmitter can be detected.
4. Flow computer signal channel detection:
by utilizing the constant current source function of ConsT811, 8 signal channels of the flow computer can be detected at one time, and the signal channels are verified and checked:
(1) Pressure, differential pressure signal channel detection
First, the pressure channel signal line (pressure+, pressure-or differential pressure+, differential pressure-) of the 8 flow computers (signal transmission is standard (4-20) mA current signal) to be tested is correctly connected with the 8-path 2-line power line of the signal output of the current/voltage conversion circuit 4. If the 1 path of V < 1+ > is positively connected with the 1 st transmitter power supply, V < 1 > -is negatively connected with the 1 st transmitter power supply until the 8 path of V < 8+ > is positively connected with the 8 th transmitter power supply, and V < 8 > -is negatively connected with the 8 th transmitter power supply.
When the pressure and differential pressure signal channels use ConsT811 constant current source as standard current signal to detect the channels, as shown in figure 4, the power negative (-) of the active current source of the ConsT811 pressure checking instrument is connected with the signal input No. 3 terminal of the current/voltage conversion circuit, the current negative (-) of the active current source is connected with the signal input No. 2 terminal of the current/voltage conversion circuit, meanwhile, the output mode of ConsT811 is current, the power supply mode is internal power, then the ConsT811 outputs standard current of 4mA, 8mA, 12mA, 16mA and 20mA to the pressure (or differential pressure) signal channels, and the checking/calibrating is carried out on the 8 flow computer pressure and differential pressure signal channels with the same current value respectively through the change-over switch 2 until the checking/calibrating of the detection points of the 8 flow computer signal pressure signal channels are all completed.
(2) Temperature signal channel detection:
first, the temperature channel signal line (temperature+, temperature-) of the 8 flow computers (the signal transmission is the standard (4-20) mA current signal) to be tested is correctly connected with the 8-path 2-line power line of the signal output of the current/voltage conversion circuit 4. If the 1 path of V < 1+ > is positively connected with the 1 st transmitter power supply, V < 1 > -is negatively connected with the 1 st transmitter power supply until the 8 path of V < 8+ > is positively connected with the 8 th transmitter power supply, and V < 8 > -is negatively connected with the 8 th transmitter power supply.
When the temperature signal channel uses a ConsT811 constant current source as a standard current signal for channel detection, as shown in fig. 5, mA+ of a ConsT811 pressure calibrator is connected with an input signal No. 2 terminal of a current/voltage conversion circuit 4, mA is connected with a signal input No. 3 terminal of the current/voltage conversion circuit 4, meanwhile, the output mode of the ConsT811 is current, the power supply mode is an internal power supply, then standard currents of 4mA, 8mA, 12mA, 16mA and 20mA are output to the temperature signal channel by the ConsT811, and verification/calibration is carried out on 8 flow computer temperature signal channels with the same current value respectively through a change-over switch 2 until all detection points of the 8 flow computer temperature signal channels are verified/calibrated.
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the invention.
Claims (9)
1. The multichannel detection device suitable for the transmitter and the flow computer comprises a detection module and an alternating current/direct current conversion circuit which are electrically connected with each other, and is characterized in that the detection module comprises a change-over switch and a plurality of detection units electrically connected with the change-over switch;
the detection unit comprises a current/voltage conversion circuit, a thermal resistance value conversion circuit, a first wire connector and a second wire connector;
the current/voltage conversion circuit and the thermal resistance value conversion circuit are electrically connected with each other; the first connector is electrically connected with the current/voltage conversion circuit and is used for externally connecting a current source; the second connector is electrically connected with the thermal resistance value conversion circuit and is used for externally connecting a direct current resistor;
the change-over switch is used for switching the detection unit connected with the change-over switch.
2. The multi-channel sensing device of claim 1, wherein the first connector comprises 3 connection ports, and the current/voltage conversion circuit comprises a relay switch and positive and negative sensing ports for connecting the transmitter to be sensed;
the port 1 of the first connector is electrically connected with the change-over switch;
the driving coil of the relay switch is electrically connected with the change-over switch, two ends of a contact of the relay switch are respectively electrically connected with a No. 2 port and a positive detection port of the first connector, and a negative detection port is electrically connected with a No. 3 port of the first connector.
3. The multi-channel detector for use in a transmitter and a flow computer of claim 2, wherein a protection circuit is provided between the ac/dc conversion circuit and port No. 1 of the first connector.
4. The multi-channel sensing device of claim 3, wherein the protection circuit comprises a current limiting resistor and a reverse diode electrically connected in sequence.
5. The multi-channel sensing device of claim 2 adapted for use with a transmitter and a flow computer, wherein the first connector further comprises a back-up port.
6. The multi-channel detector for use in transmitters and flow computers according to any one of claims 2-5, wherein the relay switch is a photoelectric isolation relay.
7. The multi-channel detector of claim 1, wherein the second connector comprises n connection ports, the thermal resistance value conversion circuit comprises n relay switches and a resistance port for connecting a thermal resistor, and n is an integer greater than 1;
the driving coil of the ith relay switch is electrically connected with the current/voltage conversion circuit corresponding to the detection unit, and two ends of a contact of the relay switch are respectively electrically connected with an i-number port and a resistance port of the second connector, i epsilon [1, n ].
8. The multi-channel sensing device of claim 7 adapted for use with transmitters and flow computers wherein the relay switch is a photo-electrically isolated relay.
9. The multi-channel sensing device of claim 1 adapted for use with transmitters and flow computers wherein any two of said sensing units have a line resistance deviation of less than 5mΩ.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210453781.4A CN117007209A (en) | 2022-04-27 | 2022-04-27 | Multichannel detection device suitable for transmitter and flow computer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210453781.4A CN117007209A (en) | 2022-04-27 | 2022-04-27 | Multichannel detection device suitable for transmitter and flow computer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117007209A true CN117007209A (en) | 2023-11-07 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210453781.4A Pending CN117007209A (en) | 2022-04-27 | 2022-04-27 | Multichannel detection device suitable for transmitter and flow computer |
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| Country | Link |
|---|---|
| CN (1) | CN117007209A (en) |
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2022
- 2022-04-27 CN CN202210453781.4A patent/CN117007209A/en active Pending
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