A portable online conductivity meter electrode constant testing device and testing method

Abstract

The invention relates to a portable online conductivity meter electrode constant testing device and a testing method. The device comprises the following steps: fixing an electrode to be tested in a conductivity flow cell B, connecting the electrode of the conductivity meter to be tested to a corresponding electrode terminal to be tested on a wiring panel through a lead wire; turning on a power switch of a secondary instrument of a standard conductivity meter; connecting drainage pipes to drainage pipes at drainage ports of two conductivity flow cells; connecting a water sample whose conductivity meets the testing requirements to a sampling pipe; adjusting flow control valves respectively so that the flow indicated by a float flowmeter is the same and meets the measurement requirements; turning four single-pole double-throw switches on the wiring panel to a side connected to a standard electrode terminal, and reading a display value of a secondary instrument of the standard conductivity meter; and then turning four single-pole double-throw switches on the wiring panel to a side connected to a electrode terminal to be tested, and reading a display value of the secondary instrument; and calculating the electrode constant of the electrode to be tested with reference to DL / T 677-2009 "Testing Procedures for Online Chemical Instruments in Power Plants".

Description

Technical Field

[0001] The invention relates to a conductivity meter testing device, in particular to a portable online conductivity meter electrode constant testing device and a testing method. Background Art

[0002] The electrode constant is a key parameter of the conductivity meter electrode. The manufacturer will mark an initial factory value on the electrode. Online conductivity meters usually continuously measure the conductivity of flowing water samples. After a period of use, dirt will form on the electrode surface, and the electrode constant will change. However, the transmitter of the meter (the secondary instrument of the standard conductivity meter) is still set to the factory electrode constant value, and the measured value will be inaccurate. In order to ensure the accuracy of conductivity measurement, the meter maintenance personnel will clean the electrode regularly, but after each cleaning, it cannot be guaranteed that the power plant constant can be restored to the factory value, so the electrode constant should be checked regularly.

[0003] There are two methods for testing the electrode constant: the standard solution method and the standard electrode method. For the water vapor system of a thermal power plant, the electrode constant of the conductivity meter is usually less than 0.1, and the conductivity of the measured water samples is mostly less than 10μS / cm. Since the low-conductivity standard solution is easily affected by air, the low-conductivity standard solution cannot be used to test the electrode constant of such electrodes, and only the standard electrode method can be used for testing.

[0004] DL / T 677-2009 "Testing Procedures for Online Chemical Instruments in Power Plants" describes the method of testing electrode constants using the standard electrode method. However, due to the lack of an integrated electrode constant testing device, the various components are scattered and an external power supply is required for each test. Each time a conductivity meter electrode constant is tested, a series of operations must be performed, including re-building temporary pipelines, connecting standard electrodes, disassembling standard electrodes, connecting electrodes to be tested, and disassembling electrodes to be tested. The process is cumbersome and the workload is large, which brings many inconveniences to instrument maintenance.

[0005] SUMMARY OF THE INVENTION

[0006] In order to solve the above problems, the present invention provides a portable online conductivity meter electrode constant testing device and testing method.

[0007] The invention has the following contents: a portable online conductivity meter electrode constant test device, which includes a sampling tube, a flow control valve, a filter, a cooler, a float flowmeter, a conductivity flow cell, a standard conductivity meter electrode, a standard conductivity meter secondary instrument, a power switch, a battery and a wiring panel, the wiring panel includes a standard electrode terminal, an electrode terminal to be tested and a single-pole double-throw switch, and also includes a conductivity meter electrode to be tested, characterized in that the sampling tube is connected to the flow control valve C, the flow control valve C is connected to the filter through a pipeline, the filter is connected to the cooler through a pipeline, and the pipeline connected to the rear end of the cooler is divided into a branch pipeline A and a branch pipeline B;

[0008] The branch pipeline A is connected to the flow control valve A, the flow control valve A is connected to the float flowmeter A through a pipeline, the float flowmeter A is connected to the conductivity flow cell A through a pipeline, the standard electrode is fixed in the conductivity flow cell A, and the standard electrode is connected to four standard electrode terminals on the wiring panel through four lead wires;

[0009] The branch pipeline B is connected to the flow control valve B, the flow control valve B is connected to the float flowmeter B through a pipeline, the float flowmeter B is connected to the conductivity flow cell B through a pipeline, the conductivity meter electrode to be tested is fixed in the conductivity flow cell B, and the conductivity meter electrode to be tested is connected to four electrode terminals to be tested on the wiring panel through four lead wires;

[0010] The wiring panel includes four single-pole double-throw switches, each of which includes three pins. The pins at both ends of each single-pole double-throw switch are respectively connected to a standard electrode terminal and an electrode terminal to be tested at corresponding positions through leads, and the middle pin of each single-pole double-throw switch is connected to a secondary instrument of a standard conductivity meter through a lead.

[0011] Preferably, the secondary instrument of the standard conductivity meter is connected to the battery via a wire, and a power switch is installed between the wire connecting the secondary instrument of the standard conductivity meter and the battery.

[0012] Preferably, the conductivity flow cell A and the conductivity flow cell B are respectively provided with a drain port A and a drain port B, and each drain port is respectively connected to a drain pipe.

[0013] Preferably, the single-pole double-throw switch can be replaced by a three-pin two-speed toggle switch, which also includes three pins.

[0014] A testing method using the portable online conductivity meter electrode constant testing device described above, the specific steps are as follows:

[0015] ①Fix the electrode to be tested into conductivity flow cell B, and connect the conductivity meter electrode to be tested to the corresponding electrode terminal to be tested on the wiring panel through the lead wire;

[0016] ② Turn on the power switch of the secondary instrument of the standard conductivity meter; connect the drain outlets of the two conductivity flow cells to the drain pipes respectively; connect the sampling tube to the water sample whose conductivity meets the test requirements (the conductivity of the water sample is within the conductivity range of the water sample normally measured by the electrode under test);

[0017] ③ Adjust flow control valve A, flow control valve B and flow control valve C respectively, so that the flow indicated by float flowmeter A and float flowmeter B is the same and meets the measurement requirements, turn all four single-pole double-throw switches on the wiring panel to the side connected to the standard electrode terminal, and read the display value of the secondary instrument of the standard conductivity meter;

[0018] ④ Then turn all four single-pole double-throw switches on the wiring panel to the side connected to the electrode terminal to be tested, and read the display value of the secondary instrument;

[0019] ⑤ Calculate the electrode constant of the electrode being tested according to DL / T 677-2009 "Test Procedure for Online Chemical Instruments in Power Plants".

[0020] Beneficial effects of the present invention

[0021] ① The present invention can test the electrode constant based on the standard electrode method, and the operation is simple, convenient and fast, eliminating the steps of building temporary pipelines, connecting and disassembling standard electrodes when testing the electrode constant of each online conductivity meter, thereby improving the testing efficiency and reducing the workload of maintenance personnel.

[0022] ② The present invention can filter and cool the water sample taken during the inspection; the sampling pipeline is provided with a flow control valve and a float flowmeter, which can adjust the flow of the water sample according to the inspection requirements; the wiring panel is provided with a single-pole double-throw switch, which can directly switch the connection between the control standard electrode or the conductivity meter electrode to be inspected and the secondary instrument, avoiding the need to disassemble the standard electrode back and forth;

[0023] ③ The storage battery equipped in the present invention can supply power to the secondary instrument of the standard conductivity meter, and no external power supply is required when in use. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of the overall structure of a portable online conductivity meter electrode constant testing device;

[0025] In the figure: 1. sampling tube, 2. flow control valve C, 3. filter, 4. cooler, 5. branch pipeline B, 6. branch pipeline A, 7. flow control valve A, 8. float flowmeter A, 9. flow control valve B, 10. float flowmeter B, 11. conductivity flow cell B, 12. conductivity flow cell A, 13. drain outlet B, 14. drain outlet A, 15. standard conductivity meter electrode, 16. conductivity meter electrode to be tested, 17. electrode terminal to be tested, 18. single-pole double-throw switch, 19. standard electrode terminal, 20. wiring panel, 21. standard conductivity meter secondary instrument, 22. power switch, 23. battery. DETAILED DESCRIPTION

[0026] Implementation Case 1

[0027] See also Figure 1 , a portable online conductivity meter electrode constant test device, the device includes a sampling tube, a flow control valve, a filter, a cooler, a float flowmeter, a conductivity flow cell, a standard conductivity meter electrode, a standard conductivity meter secondary instrument, a power switch, a battery and a wiring panel, the wiring panel includes a standard electrode terminal, an electrode terminal to be tested and a single-pole double-throw switch, characterized in that the sampling tube is connected to the flow control valve C, the flow control valve C is connected to the filter through a pipeline, the filter uses a filter with a replaceable filter element, the filter can prevent impurities in the water sample from contaminating the sampling pipeline and the conductivity flow cell, the filter is connected to the cooler through a pipeline, the cooler can use a portable cooling device for chemical instrument inspection, and the pipeline connected to the rear end of the cooler is divided into a branch pipeline A and a branch pipeline B;

[0028] The branch pipeline A is connected to the flow control valve A, the flow control valve A is connected to the float flowmeter A through a pipeline, the float flowmeter A is connected to the conductivity flow cell A through a pipeline, the standard electrode is fixed in the conductivity flow cell A, and the standard electrode is connected to four standard electrode terminals on the wiring panel through four lead wires;

[0029] The branch pipeline B is connected to the flow control valve B, the flow control valve B is connected to the float flowmeter B through a pipeline, the float flowmeter B is connected to the conductivity flow cell B through a pipeline, the conductivity meter electrode to be tested is fixed in the conductivity flow cell B, and the conductivity meter electrode to be tested is connected to four electrode terminals to be tested on the wiring panel through four lead wires;

[0030] The wiring panel includes four single-pole double-throw switches, each of which includes three pins. The pins at both ends of each single-pole double-throw switch are respectively connected to a standard electrode terminal and an electrode terminal to be tested at corresponding positions through leads, and the middle pin of each single-pole double-throw switch is connected to a secondary instrument of a standard conductivity meter through a lead. The single-pole double-throw switch can be used to control the standard electrode, the electrode of the conductivity meter to be tested and the secondary instrument of the standard conductivity meter to be connected, and the conductivity value displayed by the secondary instrument of the standard conductivity meter is switched.

[0031] The secondary instrument of the standard conductivity meter is connected to the battery through a wire, and a power switch is installed between the wire connecting the secondary instrument of the standard conductivity meter and the battery.

[0032] The conductivity flow cell A and the conductivity flow cell B are respectively provided with a drain port A and a drain port B, and each drain port is respectively connected to a drain pipe.

[0033] The single-pole double-throw switch can be replaced by a three-pin two-speed toggle switch, which also includes three pins.

[0034] The present invention can test the electrode constant based on the standard electrode method, and the operation is simple, convenient and fast. The steps of building a temporary pipeline, connecting and disassembling the standard electrode are omitted when testing the electrode constant of each online conductivity meter. The inspection efficiency can be improved and the workload of maintenance personnel can be reduced. The water sample taken can be filtered and cooled during the inspection. A flow control valve and a float flowmeter are arranged on the sampling pipeline, and the flow of the water sample can be adjusted according to the inspection requirements. A single-pole double-throw switch is arranged on the wiring panel, and the connection between the standard electrode or the conductivity meter electrode to be tested and the secondary instrument can be directly switched to avoid disassembling the standard electrode back and forth. The equipped storage battery can power the secondary instrument of the standard conductivity meter, and no external power supply is required during use.

[0035] Implementation case 2:

[0036] See also Figure 1 , a method for testing a portable online conductivity meter electrode constant testing device as described in the first application implementation case, the specific steps are as follows:

[0037] ①Fix the electrode to be tested into conductivity flow cell B, and connect the conductivity meter electrode to be tested to the corresponding electrode terminal to be tested on the wiring panel through the lead wire;

[0038] ② Turn on the power switch of the secondary instrument of the standard conductivity meter; connect the drain outlets of the two conductivity flow cells to the drain pipes respectively; connect the sampling tube to the water sample whose conductivity meets the test requirements (the conductivity of the water sample is within the conductivity range of the water sample measured normally by the electrode under test);

[0039] ③ Adjust flow control valve A, flow control valve B and flow control valve C respectively, so that the flow indicated by float flowmeter A and float flowmeter B is the same and meets the measurement requirements, turn all four single-pole double-throw switches on the wiring panel to the side connected to the standard electrode terminal, and read the display value of the secondary instrument of the standard conductivity meter;

[0040] ④ Then turn all four single-pole double-throw switches on the wiring panel to the side connected to the electrode terminal to be tested, and read the display value of the secondary instrument;

[0041] ⑤ Calculate the electrode constant of the electrode being tested according to DL / T 677-2009 "Test Procedure for Online Chemical Instruments in Power Plants".

Claims

1. A portable online conductivity meter electrode constant test device, the device comprises a sampling tube, a flow control valve, a filter, a cooler, a float flowmeter, a conductivity flow cell, a standard conductivity meter electrode, a standard conductivity meter secondary instrument, a power switch, a battery and a wiring panel, the wiring panel comprises a standard electrode terminal, an electrode terminal to be tested and a single-pole double-throw switch, and also comprises a conductivity meter electrode to be tested, characterized in that: The sampling tube is connected to the flow control valve C, the flow control valve C is connected to the filter through a pipeline, the filter is connected to the cooler through a pipeline, and the pipeline connected to the rear end of the cooler is divided into a branch pipeline A and a branch pipeline B; The branch pipeline A is connected to the flow control valve A, the flow control valve A is connected to the float flowmeter A through a pipeline, the float flowmeter A is connected to the conductivity flow cell A through a pipeline, the standard electrode is fixed in the conductivity flow cell A, and the standard electrode is connected to four standard electrode terminals on the wiring panel through four lead wires; The branch pipeline B is connected to the flow control valve B, the flow control valve B is connected to the float flowmeter B through a pipeline, the float flowmeter B is connected to the conductivity flow cell B through a pipeline, the conductivity meter electrode to be tested is fixed in the conductivity flow cell B, and the conductivity meter electrode to be tested is connected to four electrode terminals to be tested on the wiring panel through four lead wires; The wiring panel includes four single-pole double-throw switches, each of which includes three pins. The pins at both ends of each single-pole double-throw switch are respectively connected to a standard electrode terminal and an electrode terminal to be tested at corresponding positions through lead wires, and the middle pin of each single-pole double-throw switch is connected to a secondary instrument of a standard conductivity meter through a lead wire. The secondary instrument of the standard conductivity meter is connected to the battery through a wire, and a power switch is installed between the wire connecting the secondary instrument of the standard conductivity meter and the battery; The conductivity flow cell A and the conductivity flow cell B are respectively provided with a drain port A and a drain port B, and each drain port is respectively connected to a drain pipe.

2. A portable online conductivity meter electrode constant testing device according to claim 1, characterized in that: The single-pole double-throw switch can be replaced by a three-pin two-speed toggle switch, which also includes three pins.

3. A method for testing a portable online conductivity meter electrode constant testing device according to claim 1, comprising the following steps: ①Fix the electrode to be tested into conductivity flow cell B, and connect the conductivity meter electrode to be tested to the corresponding electrode terminal to be tested on the wiring panel through the lead wire; ② Turn on the power switch of the secondary instrument of the standard conductivity meter; connect the drain outlets of the two conductivity flow cells to the drain pipes respectively; The sampling tube is connected to a water sample whose conductivity meets the test requirements, that is, the conductivity of the water sample taken is within the conductivity range of the water sample normally measured by the electrode under test; ③ Adjust flow control valve A, flow control valve B and flow control valve C respectively, so that the flow indicated by float flowmeter A and float flowmeter B is the same and meets the measurement requirements, turn all four single-pole double-throw switches on the wiring panel to the side connected to the standard electrode terminal, and read the display value of the secondary instrument of the standard conductivity meter; ④ Then turn all four single-pole double-throw switches on the wiring panel to the side connected to the electrode terminal to be tested, and read the display value of the secondary instrument; ⑤ Calculate the electrode constant of the electrode being tested according to DL / T 677-2009 "Test Procedure for Online Chemical Instruments in Power Plants".

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