Device and method for detecting resistance of electric heating belt of heat preservation pipe
Technical Field
The invention belongs to the technical field of resistance detection, and relates to a device and a method for detecting the resistance of an electric heating belt of a heat-insulating pipe.
Background
The heat preservation pipe is mainly used for heat preservation engineering of heat medium, the electric heating belt is used as an important component in the heat preservation pipe, and heat of the heat medium cannot be lost in the heat preservation pipe through the heating function of the electric heating belt. After the production is completed, in order to ensure that the thermal insulation pipe can normally work in a low-temperature environment, the resistance parameters of the electric heating tape in the thermal insulation pipe need to be detected, such as the insulation resistance detection and the direct current resistance detection of the electric heating tape.
At present, when the direct current resistance and the insulation resistance of an electric heating belt in a heat preservation pipe are detected, various devices are required to be used for testing item by item, cables need to be manually switched to detect in the testing process, and the measuring efficiency is low.
Disclosure of Invention
The invention aims to provide a device and a method for detecting the resistance of an electric heating strip of a heat-insulating pipe, wherein equipment required by a test item detected by the electric heating strip is integrated in a test box body, a control unit controls a high-voltage switch matrix module and a low-voltage switch matrix module to realize test channel switching, and manual switching is not required in the test process.
The invention is realized by the following technical scheme:
a resistance detection device for an electric heating belt of a heat preservation pipe comprises a control part and a test part;
the control part comprises a control unit and a communication card;
the testing part comprises an insulation resistance tester, a micro resistance meter and a power socket with a filter, wherein the insulation resistance tester, the micro resistance meter and the power socket are arranged on a front panel of the testing box body; the test box body is internally provided with a main control module and a power supply module for supplying power to the main control module, and the power supply module, the insulation resistance tester and the micro resistance meter are all supplied with power by a power socket with a filter; the main control module consists of a power distribution module, a high-voltage isolation control module, a low-voltage isolation control module, a high-voltage switch matrix module, a low-voltage switch matrix module and a core board which is connected with the main control board through a connector module, wherein the power distribution module, the high-voltage isolation control module, the low-voltage isolation control module, the high-voltage switch matrix module and the low-voltage switch matrix module are arranged on the main control board; the power distribution module is used for converting the power supply output by the power supply module into voltage suitable for the main control module;
an insulation resistance test command sent by the control unit is output to the insulation resistance tester and the core board through the communication card, the core board executes the insulation resistance test command and outputs an insulation resistance test signal through the connector module, the insulation resistance test signal is isolated by the high-voltage isolation control module and then output to the high-voltage switch matrix module, the high-voltage switch matrix module executes the insulation resistance test signal to switch a test channel and perform an electrical heating belt insulation resistance test, the high-voltage switch matrix module transmits a test feedback signal to the insulation resistance tester, the insulation resistance tester reads an insulation resistance value, and the insulation resistance tester transmits the insulation resistance value to the control unit through the communication card;
the direct current resistance test command that the control unit sent is exported to little resistance meter and nuclear core plate through the communication card, by nuclear core plate carries out direct current resistance test command and exports direct current resistance test signal through the connector module, and direct current resistance test signal exports to low-voltage switch matrix module after being kept apart by low-voltage isolation control module, and low-voltage switch matrix module carries out direct current resistance test signal and switches over the test channel and carry out electric heating area direct current resistance test, and low-voltage switch matrix module transmits test feedback signal to little resistance meter, reads direct current resistance value by little resistance meter, and little resistance meter transmits direct current resistance value to the control unit by the communication card.
Furthermore, an insulation resistance test interface and an insulation resistance test hole which are connected with the high-voltage switch matrix module are arranged on the front panel of the test box body, a direct-current resistance test interface and a direct-current resistance test hole which are connected with the low-voltage switch matrix module are also arranged on the front panel of the test box body, and a communication interface which is connected with the main control module, the insulation resistance tester and the micro resistance meter is also arranged on the front panel of the test box body;
the communication interface is connected with a communication card in the control unit through a communication cable; the insulation resistance test interface and the direct current resistance test interface are both connected with the electric heating belt through resistance test cables; the insulation resistance test hole and the insulation resistance tester and the direct current resistance test hole and the micro resistance meter are connected through test cables.
Furthermore, the low-voltage switch matrix module is internally provided with six groups of direct-current resistance testing channels, each direct-current resistance testing channel consists of four relays connected in parallel, and each relay consists of the following components:
two ends of the relay coil are respectively connected with the power distribution module and the low-voltage isolation control module; and two ends of the relay contactor are respectively connected with the direct current resistance testing interface and the direct current resistance testing hole.
Further, the inside six insulation resistance test channels that are equipped with of high voltage switch matrix module, insulation resistance test channel comprises double-circuit high voltage relay, and every double-circuit high voltage relay's constitution is as follows:
two ends of the double-path high-voltage relay coil are respectively connected with the power distribution module and the high-voltage isolation control module; two ends of two contactors of the double-path high-voltage relay are respectively connected with the insulation resistance test interface and the insulation resistance test hole.
Further, resistance test cable all is equipped with the crocodile and presss from both sides with each inner core of electrical heating area link, and the other end of resistance test cable is equipped with the aviation plug.
A method for detecting the resistance of an electric heating belt of a heat preservation pipe comprises the following specific steps:
s1: turning on a control unit power supply and a test box power supply;
s2: connecting the communication card of the control unit with the communication interface of the test box body by using a communication cable; connecting the insulation resistance test interface and the direct current resistance test interface with each electric heating belt in the heat preservation pipe respectively by using a resistance test cable; connecting the direct current resistance test hole with a micro resistance meter by using a test cable, and connecting the insulation resistance test hole with an insulation resistance tester by using the test cable;
s3: detecting the on-off of a communication cable, a resistance test cable and a test cable through a control unit; if the normal operation cannot be carried out, returning to S2; otherwise, entering S4 to continue operation;
s4: selecting a resistance test task through the control unit, and if a direct current resistance test is selected, entering S5 to continue running; otherwise, entering S10 to operate;
s5: the control unit outputs a direct current resistance test command to the micro resistance meter and the core board through the communication card;
s6: marking a direct current resistance test channel as i through a core board Straight bar ,i Straight bar =1;
S7: the core board controls the low-voltage switch matrix module to switch the test channel i in sequence through the connector module and the low-voltage isolation control module Straight bar A closed loop is formed among the micro-resistance meter, the low-voltage matrix module and the electric heating belt to realize the test channel i Straight bar Detecting the direct current resistance of the corresponding electric heating belt;
s8: the micro resistance meter transmits the resistance value of the direct current resistor to the control unit through the communication card;
s9: let i Straight bar =i Straight bar +1, if i Straight bar +1<7, then i is Straight bar +1 as i Straight bar Returning to S7 to repeat the steps; otherwise, ending the direct currentA resistance test task;
s10: the control unit outputs an insulation resistance test command to the insulation resistance tester and the core board through the communication card;
s11: marking the insulation resistance test channel as i through the core board Insulation for a building ,i Insulation board =1;
S12: the core board controls the high-voltage switch matrix module to sequentially switch the test channel i through the connector module and the high-voltage isolation control module Insulation board A closed loop is formed among the insulation resistance tester, the high-voltage matrix module and the electric heating belt, so that the insulation resistance detection of the electric heating belt is realized;
s13: the insulation resistance tester transmits the resistance value of the insulation resistance to the control unit through the communication card;
s14: let i Insulation for a building =i Insulation board +1, if i Insulation board +1<7, then i is Insulation board +1 as i Insulation board Returning to S12 to repeat the steps; otherwise, ending the insulation resistance test task.
Compared with the prior art, the invention has the following beneficial technical effects:
1. according to the invention, the insulation resistance tester and the micro resistance meter for the electric heating belt detection project are integrated in the test box body, and the tidiness of a test field is ensured in the test process; and when testing, accessible control unit control nuclear core plate makes singlechip control high voltage switch matrix module, low voltage switch matrix module realize the switching of a plurality of test channels, need not artifical switching electric heating tape in the testing process can realize the insulation resistance or the direct current resistance test to all electric heating tapes in the insulating tube, and the testing process connectivity is good, and can realize automatic test, has improved direct current resistance or insulation resistance's efficiency of software testing.
2. The connector module is used for connecting the core board with the power distribution module, the high-voltage isolation control module and the low-voltage isolation control module on the main control board, so that the core board can conveniently control the modules on the main control board to realize corresponding functions; the high-voltage isolation control module and the low-voltage isolation control module are used for transmitting control signals of the core board to the high-voltage switch matrix module and the low-voltage switch matrix module, and the high-voltage isolation control module and the low-voltage isolation control module can reduce noise of a grounding loop, so that signal transmission is not through an electrical connection or leakage path, and safety risks are avoided.
Drawings
FIG. 1 is an overall schematic view of the present invention;
FIG. 2 is a schematic view of a front panel of the test chamber of the present invention;
FIG. 3 is a circuit diagram of a power interface in the power distribution module of the present invention;
FIG. 4 is a diagram of a 5.5V voltage regulator circuit in the power distribution module of the present invention;
FIG. 5 is a circuit diagram of a 3.3V power conversion circuit in the power distribution module of the present invention;
FIG. 6 is a schematic view of a connector module of the present invention;
FIG. 7 is a circuit diagram of a high voltage isolation control module according to the present invention;
FIG. 8 is a circuit diagram of a low voltage isolation control module according to the present invention;
FIG. 9 is a circuit diagram of a high voltage switch matrix module according to the present invention;
fig. 10 is a circuit diagram of a low-voltage switch matrix module according to the present invention.
Wherein, 1 is the test box front panel, 2 is the insulation resistance tester, 3 is little resistance meter, 4 is the direct current resistance test interface, 5 is the insulation resistance test interface, 6 is the communication interface, 7 is the supply socket who takes the wave filter, 8 is the insulation resistance test hole, 9 is the direct current resistance test hole.
Detailed Description
The present invention will now be described in further detail with reference to the attached drawings, which are illustrative, but not limiting, of the present invention.
As shown in figures 1 and 2, the invention discloses a resistance detection device for an electric heating belt of a heat preservation pipe, which comprises a control part and a test part, wherein the control part is used for controlling the resistance detection device to be in a state of being in contact with the test part; the control part comprises a control unit and a communication card;
the testing part comprises an insulation resistance tester 2, a micro resistance meter 3 and a power socket 7 with a filter, which are arranged on a front panel 1 of the testing box body; the main control module and the power module for supplying power to the main control module are also arranged in the test box body, and the power module, the insulation resistance tester 2 and the micro resistance meter 3 are all supplied with power by a power socket 7 with a filter; the main control module consists of a power distribution module, a high-voltage isolation control module, a low-voltage isolation control module, a high-voltage switch matrix module, a low-voltage switch matrix module and a core board which is connected with the main control board through a connector module, wherein the power distribution module, the high-voltage isolation control module, the low-voltage isolation control module, the high-voltage switch matrix module and the low-voltage switch matrix module are arranged on the main control board; the power distribution module is used for converting the power supply output by the power supply module into voltage suitable for the main control module;
as shown in fig. 3, 4 and 5, specifically, the core board is model number STM32F429IGT6; the model of the connector module is STM32F429; the power distribution module comprises a power interface circuit, a 5V voltage stabilizing circuit and a 3.3V power conversion circuit, wherein the power interface circuit, the 5V voltage stabilizing circuit and the 3.3V power conversion circuit all adopt the prior art.
As shown in fig. 7 and 8, the high-voltage isolation control module and the low-voltage isolation control module are both composed of digital isolators and darlington transistor matrices, the digital isolators are U3, U4, U5 and U6 and have models of CA-IS3760LW, and the darlington transistor matrices are U8, U9, U10 and U11 and have models of ULN2803A;
in the high-voltage isolation control module and the low-voltage isolation control module, a VDDA pin of the digital isolator is connected with the 3.3V power supply conversion circuit, a VDDB pin is connected with the 5V voltage stabilizing circuit, and a GNDA pin is grounded; the GNDB pin of the digital isolator and the E pin of the Darlington transistor matrix are both connected with a power interface circuit of the power distribution module; the COM pin of the Darlington transistor matrix is connected with the power interface circuit; a VI1 pin, a VI2 pin, a VI3 pin, a VI4 pin, a VI5 pin and a VI6 pin of the digital isolator are respectively connected with pins on the connector module; a VO1 pin, a VO2 pin, a VO3 pin, a VO4 pin, a VO5 pin and a VO6 pin of the digital isolator are respectively connected with a 1B pin, a 2B pin, a 3B pin, a 4B pin, a 5B pin and a 6B pin of the Darlington transistor matrix in a one-to-one correspondence manner; pins 1C, 2C, 3C, 4C, 5C and 6C of a Darlington transistor matrix in the high-voltage isolation control module are connected with the high-voltage switch matrix module; pins 1C, 2C, 3C, 4C, 5C and 6C of a Darlington transistor matrix in the low-voltage isolation control module are connected with the low-voltage switch matrix module;
an insulation resistance test command sent by the control unit is output to the insulation resistance tester 2 and the core board through the communication card, the core board executes the insulation resistance test command and outputs an insulation resistance test signal through the connector module, the insulation resistance test signal is isolated by the high-voltage isolation control module and then is output to the high-voltage switch matrix module, the high-voltage switch matrix module executes the insulation resistance test signal to switch a test channel and perform an electrical heating strip insulation resistance test, the high-voltage switch matrix module transmits a test feedback signal to the insulation resistance tester 2, the insulation resistance tester 2 reads an insulation resistance value, and the insulation resistance tester 2 transmits the insulation resistance value to the control unit through the communication card;
the direct current resistance test command that the control unit sent is exported to little resistance meter 3 and core plate through the communication card, by core plate carries out direct current resistance test command and exports direct current resistance test signal through the connector module, direct current resistance test signal exports to low-voltage switch matrix module after being kept apart by low-voltage isolation control module, and low-voltage switch matrix module carries out direct current resistance test signal and switches over the test channel and carry out electric heating area direct current resistance test, and low-voltage switch matrix module transmits test feedback signal to little resistance meter 3, reads direct current resistance value by little resistance meter 3, little resistance meter 3 transmits direct current resistance value to the control unit by the communication card.
As shown in fig. 2, the front panel 1 of the testing box body is provided with an insulation resistance testing interface 5 and an insulation resistance testing hole 8 which are connected with the high-voltage switch matrix module, a direct current resistance testing interface 4 and a direct current resistance testing hole 9 which are connected with the low-voltage switch matrix module, and a communication interface 6 which is connected with the main control module, the insulation resistance tester 2 and the micro resistance meter 3;
the communication interface 6 is connected with a communication card in the control unit through a communication cable; the insulation resistance test interface 5 and the direct current resistance test interface 4 are both connected with the electric heating belt through resistance test cables; the insulation resistance test hole 8 is connected with the insulation resistance tester 2, and the direct current resistance test hole 9 is connected with the micro resistance meter 3 through test cables. Resistance test cable all is equipped with the crocodile and presss from both sides with each inner core of electrical heating area link, and the other end of resistance test cable is equipped with the aviation plug.
As shown in fig. 9, six groups of dc resistance testing channels are arranged inside the low-voltage switch matrix module, each dc resistance testing channel is composed of four relays connected in parallel, and each relay is composed of:
two ends of the relay coil are respectively connected with a power interface circuit of the power distribution module and an output pin of a Darlington transistor matrix of the low-voltage isolation control module; two ends of the relay contactor are respectively connected with the direct current resistance testing interface 4 and the direct current resistance testing hole 9.
As shown in fig. 10, the high voltage switch matrix module is internally provided with six insulation resistance testing channels, each insulation resistance testing channel is composed of two-way high voltage relays, and each two-way high voltage relay is composed of the following components:
two ends of the two-way high-voltage relay coil are respectively connected with a power interface circuit of the power distribution module and an output pin of a Darlington transistor matrix of the high-voltage isolation control module; two ends of two contactors of the two-way high-voltage relay are respectively connected with the insulation resistance testing interface 5 and the insulation resistance testing hole 8.
The invention also discloses a detection method of the electric heating belt resistance of the heat preservation pipe, which comprises the following specific steps:
s1: turning on a control unit power supply and a test box power supply;
s2: connecting the communication card of the control unit with the communication interface 6 of the test box body by using a communication cable; the insulation resistance test interface 5 and the direct current resistance test interface 4 are respectively connected with each electric heating belt in the heat preservation pipe by using a resistance test cable; connecting the direct current resistance test hole 9 with the micro resistance meter 3 by using a test cable, and connecting the insulation resistance test hole 8 with the insulation resistance tester 2 by using the test cable;
s3: detecting the on-off of the communication cable, the resistance testing cable and the testing cable through the control unit; if the normal operation cannot be carried out, returning to the S2; otherwise, entering S4 to continue operation;
s4: selecting a resistance test task through the control unit, and if a direct current resistance test is selected, entering S5 to continue running; otherwise, entering S10 to operate;
s5: the control unit outputs a direct current resistance test command to the micro resistance meter 3 and the core board through the communication card;
s6: marking the DC resistance test channel as i through the core board Straight bar ,i Straight bar =1;
S7: the core board controls the low-voltage switch matrix module to sequentially switch the test channel i through the connector module and the low-voltage isolation control module Straight bar A closed loop is formed among the micro-resistance meter 3, the low-voltage matrix module and the electric heating belt to realize the test channel i Straight bar Detecting the direct current resistance of the corresponding electric heating belt;
s8: the micro resistance meter 3 transmits the resistance value of the direct current resistance to the control unit through the communication card;
s9: let i Straight bar =i Straight bar +1, if i Straight bar +1<7, then i is Straight bar +1 as i Straight bar Returning to S7 to repeat the steps; otherwise, ending the direct current resistance test task;
s10: the control unit outputs an insulation resistance test command to the insulation resistance tester 2 and the core board through the communication card;
s11: marking the insulation resistance test channel as i through the core board Insulation board ,i Insulation for a building =1;
S12: the core board controls the high-voltage switch matrix module to switch the test channel i in sequence through the connector module and the high-voltage isolation control module Insulation for a building A closed loop is formed among the insulation resistance tester 2, the high-voltage matrix module and the electric heating belt, so that the insulation resistance detection of the electric heating belt is realized;
s13: the insulation resistance tester 2 transmits the resistance value of the insulation resistance to the control unit through the communication card;
s14: let i Insulation for a building =i Insulation board +1, if i Insulation board +1<7, then i is Insulation board +1 as i Insulation board Returning to S12 to repeat the steps; otherwise, ending the insulation resistance test task.
The embodiments given above are preferable examples for implementing the present invention, and the present invention is not limited to the above-described embodiments. Any non-essential addition and replacement made by the technical characteristics of the technical scheme of the invention by a person skilled in the art belong to the protection scope of the invention.