CN116382234A - Test method, test device and test system of DCS channel - Google Patents

Abstract

The invention discloses a testing method, a testing device and a testing system of a DCS channel, comprising the following steps: sending a test instruction to a channel to be detected in the DCS system; the test instruction is used for indicating the channel to be detected to send out an expected response signal meeting preset requirements; if an actual response signal sent by the channel to be detected in response to the test instruction is received, determining whether the channel to be detected passes the test according to the preset requirement and the actual response signal. By the method, whether the channel to be detected in the DCS system passes detection or not can be automatically detected, and the detection efficiency is improved.

Description

Test method, test device and test system of DCS channel

technical field

The invention relates to the field of DCS automatic testing, in particular to a DCS channel testing method, testing device and testing system.

Background technique

At present, the instrumentation and control industry is mainly focusing on the following links in the engineering application stage of the DCS system (distributed control system, DCS for short; also called distributed control information system, DCIS for short), hard-wiring point channels and functions Testing, communication point communication and functional testing, etc., the existing market-related automated testing devices have limited functions and efficiency. The instrument control industry urgently needs a DCS automatic planning and testing solution with complete functions, high precision, and convenient operation, and develops an automated testing method.

Contents of the invention

The technical problem to be solved by the present invention is to provide a DCS channel test method, test device and test system in order to overcome the defects of limited function and efficiency of the automatic test device in the prior art.

The present invention solves the above technical problems through the following technical solutions:

The present invention provides a kind of testing method of DCS channel, described method comprises:

Sending a test instruction to the channel to be detected in the DCS system; wherein, the test instruction is used to instruct the channel to be detected to send an expected response signal that meets preset requirements;

If an actual response signal sent by the channel to be tested in response to the test instruction is received, it is determined whether the channel to be tested passes the test according to the preset requirement and the actual response signal.

Preferably, the preset requirement is that the output value of the expected response signal is a preset value;

Wherein, the step of determining whether the channel to be detected passes the test according to the preset requirement and the actual response signal includes:

judging whether the difference between the preset value and the output value of the actual response signal meets the preset accuracy;

If so, then determine that the channel to be detected passes the accuracy test;

If not, it is determined that the channel to be detected has not passed the accuracy test.

Preferably, the test method of the DCS channel also includes the following steps:

If it is determined that the channel to be detected fails the accuracy test, a compensation signal is sent to the channel to be detected according to the error accuracy.

Preferably, the preset requirement is that the voltage value of the expected response signal is less than a preset threshold;

Wherein, the step of determining whether the channel to be detected passes the test according to the preset requirement and the actual response signal includes:

judging whether the voltage value of the actual response signal is less than a preset threshold;

If so, then determine that the channel to be detected passes the clamp test;

If not, it is determined that the channel to be detected has not passed the clamp test.

Preferably, the preset requirement is that the output value of the expected response signal is within a preset dead zone interval;

Wherein, the step of determining whether the channel to be detected passes the test according to the preset requirement and the actual response signal includes:

judging whether the output value of the actual response signal is within the preset dead zone interval;

If so, then determine that the channel to be detected passes the dead zone test;

If not, it is determined that the channel to be detected has not passed the dead zone test.

Preferably, the test method of the DCS system also includes the following steps:

If the actual response signal sent by the channel to be tested in response to the test instruction is not received, it is determined that the channel with the channel to be tested is disconnected.

Preferably, the step of sending a test instruction to the channel to be tested in the DCS system includes:

In response to the input login information, determine the corresponding test authority;

A corresponding test instruction is sent to the channel to be tested in the DCS system according to the test authority.

As a second aspect of the present invention, the present invention provides a test device for a DCS channel, including a sending module, configured to send a test command to the channel to be tested in the DCS system; wherein, the test command is used to indicate that the channel to be tested The detection channel sends an expected response signal that meets the preset requirements;

A test module, configured to determine whether the channel to be tested passes the test according to the preset requirements and the actual response signal when receiving the actual response signal sent by the channel to be tested in response to the test instruction .

Preferably, the test device of the DCS channel is connected to the channel to be tested through a relay.

As a third aspect of the present invention, the present invention provides a DCS channel test system, including a DCS system and the DCS channel test device in the second aspect of the present invention.

The positive and progressive effect of the present invention is: to send test instructions to the channel to be detected in the DCS system; and receive the actual response signal sent by the channel to be detected in response to the test command, and determine whether the channel to be detected passes through according to the actual response signal test. With complete functions, high precision and convenient operation, the DCS system can be quickly detected.

Description of drawings

FIG. 1 is a schematic flow chart of a testing method for a DCS channel in Embodiment 1 of the present invention.

FIG. 2 is a schematic diagram of a test method using a DCS channel in Embodiment 1 of the present invention.

FIG. 3 is a schematic diagram of the first structure of the equipment using the DCS channel testing method in Embodiment 1 of the present invention.

FIG. 4 is a second structural schematic diagram of the equipment using the DCS channel test method in Embodiment 1 of the present invention.

FIG. 5 is a schematic diagram of a third structure of the equipment using the DCS channel test method in Embodiment 1 of the present invention.

FIG. 6 is a schematic structural diagram of a testing device for a DCS channel in Embodiment 2 of the present invention.

Detailed ways

The present invention is further illustrated below by means of examples, but the present invention is not limited to the scope of the examples.

Example 1

Please refer to Fig. 1, the present embodiment provides a kind of test method of DCS channel, the test method of DCS channel comprises:

S1. Send a test instruction to the channel to be detected in the DCS system; wherein, the test instruction is used to instruct the channel to be detected to send an expected response signal that meets the preset requirements;

S2. If the actual response signal sent by the channel to be tested in response to the test instruction is received, determine whether the channel to be tested passes the test according to the preset requirements and the actual response signal.

In this embodiment, the channels to be detected of the DCS system can quickly determine whether each channel to be detected passes the test according to preset requirements and actual response signals, thereby improving detection efficiency. In this embodiment, the channel to be detected can be in the DCS cabinet, and each channel to be detected in the DCS cabinet is connected to the execution body of the method by communication, and the communication connection can be established through loops such as network reading and network output. In this embodiment, corresponding loops can also be established according to different channels to be detected. The channels to be detected include analog input (Analog Input, also referred to as AI), analog output (Analog Output, also referred to as AO), digital Input (Digital Input, also referred to as DI), digital output (Digital Output, also referred to as DO), thermal resistance (also referred to as RTD), and thermocouple (also referred to as TC) and other types of channels to be detected. In this embodiment, the channel to be tested of analog output, digital output, thermal resistance and thermocouple type, the communication path from the test equipment end to the channel end to be tested is a read link, and the path from the channel to be tested to the test device for the output path. However, for the analog output and the channel to be tested of the analog output, the path from the channel to be tested to the test device is the output path, and the path from the test device to the channel to be tested is the read path.

Referring to FIG. 2 , in this embodiment, the channel to be detected may also be various modules of a certain device, such as an AI module, an AO module, an RTC module, a TC module, and the like. The test equipment includes a matrix adapter card, and the matrix adapter card can be connected with each module. The main control module in the test equipment is connected with the process calibrator and the upper computer, and the main controller can control the connection and disconnection of the corresponding matrix adapter card to connect with the corresponding module.

Please refer to Fig. 3 and Fig. 4, in the test device in the present embodiment, can comprise KVM (the abbreviation of keyboard, display device, mouse), switchboard and UPS (abbreviation of Uninterruptible Power Supply, uninterruptible power supply), the first conditioner Chassis, second conditioning chassis, host computer. The first conditioning chassis and the second conditioning chassis are connected to the switch through an RJ45 network cable, and the DCS cabinet is connected to the switch through an optical fiber. The upper computer runs on the industrial computer and is controlled by a control unit (which may be called CU). The test equipment can include an analog input/output module for analog input/output; it can also include a thermal resistance input/output module for thermal resistance analog signal input/output; it can also include a thermocouple input/output Module for input/output of thermocouple analog signals. Certainly, a digital input/output module may also be included in this embodiment. In this embodiment, the analog input/output module, the thermal resistance input/output module, the thermocouple input/output module and the thermocouple input/output module can be arranged in the same cabinet through cabinet clips.

In an optional embodiment, the preset requirement is that the output value of the expected response signal is a preset value;

Wherein, the step of determining whether the channel to be detected passes the test according to the preset requirements and the actual response signal includes:

judging whether the difference between the preset value and the output value of the actual response signal meets the preset accuracy;

If so, it is determined that the channel to be detected passes the precision test;

If not, it is determined that the channel to be detected has not passed the accuracy test.

In this embodiment, when testing the accuracy of the channel to be detected, the output value of the expected response signal of the channel to be detected can be the same as the output value of the test command. The difference between the output values is zero.

At this time, it can be judged whether the difference between the preset value and the output value of the actual response signal meets the preset accuracy, for example, the preset accuracy is less than 0.25°C.

In this embodiment, it is also possible to send test instructions to different channels to be tested. The OMEGA company CL3001 process calibrator can be selected to cooperate with switching different channels to be tested, and to determine whether the channel to be tested meets the accuracy requirements according to the expected response signal.

In this embodiment, the power supply connects an external power supply (generally 220V 50Hz AC) to the input terminal of the UPS, the UPS supplies power to the distribution box, and the power supply box supplies power to each device in the chassis.

Please refer to Fig. 5. In this embodiment, the analog output module can be set in the cabinet in the form of the following clips. The first clip in the cabinet can be used for signal selection of various types of signals, through hard wiring and process Connect to the AI (voltage and current are the same terminals) port, RTD output port, and TC output port of the calibrator (CL3001). The second to ninth slots of the chassis are correspondingly installed with the second card to the ninth card. Each card includes a relay, and the relay in the card is controlled by software to open or close to select the second card. Different types of signals of a card are correspondingly input to the channel to be detected. A tenth card is installed in the tenth card, and the tenth card outputs the active voltage and passive/active current signals through hard wiring. An eleventh card is installed in the eleventh slot for selecting the active voltage and passive/active current signals in the tenth card and inputting them to the tenth card. The twelfth slot to the fifteenth slot are installed corresponding to the twelfth card and the fifteenth card. The fifteenth card includes a relay inside, and the signal input of the tenth card is controlled by controlling the opening and closing of the relay. to different devices to be tested.

When it is necessary to collect voltage/active current/passive current, the software controls the internal relay of the first card in the first slot, and selects the AI signal to conduct with the output port. The output terminals are respectively connected to the input terminals of the second card to the ninth card, and the control unit collects 64 voltages/active currents/passive signals (non-simultaneous acquisition, only one channel can be collected at a time).

When the TC signal needs to be output, the software controls the internal relay of the first card, and selects the TC signal to conduct with the output port. The output terminals are respectively connected to the input terminals of the second card to the ninth card, and can output 64 channels of TC signals to the CU. For TC output, the voltage loss on the prefabricated cable is compensated by calibrating each range. The output thermocouple signal indicators are shown in the table below.

In the above embodiment, the preset accuracy may be the accuracy required by the technical specification in the above table. When the RTD signal needs to be output, the software controls the relay inside the first card to select the RTD signal to be connected to the output port. The output terminals are respectively connected to the input terminals of the ninth card of the second card, and can output 64 channels of RTD signals to the CU.

When outputting RTD, the relay inside the card can be controlled by software to control its conduction or disconnection to realize four-wire or three-wire output.

Of course, this embodiment can also test the thermocouple, and the following table shows the TC signal index of a certain thermocouple.

The test design of the above three signals can realize that AI, TC, and RTD share the same set of cables.

When the active voltage/active current/passive current signal needs to be output, the internal relay of the eleventh card is controlled to select the active voltage/active current/passive current signal to conduct with the output port. The output ends are respectively short-circuited with the input ends of the twelfth card to the fifteenth card, and 64 channels of active voltage/active current/passive current signals can be output to the CU.

In an optional embodiment, the test method of the DCS channel also includes the following steps:

If it is determined that the channel to be detected fails the accuracy test, a compensation signal is sent to the channel to be detected according to the error accuracy.

In this embodiment, for example, the channel to be detected is a thermocouple, and the detection range required in the technical specification is 400-1600°C. At this time, a type B thermocouple can be selected to meet the requirements of the technical specification. At this time, the accuracy required by the technical specification is less than or equal to 0.25°C. At this time, if the difference between the preset value and the output value of the actual response signal is less than or equal to 0.25°C (for example, the difference is 0.1-0.25°C), it can be determined that the channel to be detected meets the accuracy required by the technical specification.

In this embodiment, if the output value of the expected response signal is 1500°C, but the output value of the actual response signal is 1501°C, then the error is 1°C, but the error required by the preset accuracy is less than or equal to 0.25°C. When the time error exceeds the error corresponding to the preset accuracy, the accuracy of the channel to be detected does not meet the requirements at this time, and a corresponding compensation signal can be sent to the channel to be detected to inform that the output of the channel to be detected is reduced by 1°C (to achieve output 1500°C), so that the accuracy of the channel to be detected meets the requirements again.

In an optional embodiment, the preset requirement is that the voltage value of the expected response signal is less than a preset threshold;

Wherein, the step of determining whether the channel to be detected passes the test according to the preset requirements and the actual response signal includes:

judging whether the voltage value of the actual response signal is less than a preset threshold;

If so, it is determined that the channel to be detected passes the clamp test;

If not, it is determined that the channel to be detected has not passed the clamp test.

In this embodiment, clamping voltages can be set for certain channels to be detected. For example, the clamp voltage can be set to 5V, and a voltage of 6V can be sent to the channel to be detected. If the output value of the actual response signal returned is less than or equal to 5V, it can be determined that the channel to be detected has passed the clamp test.

In an optional embodiment, the preset requirement is that the output value of the expected response signal is within a preset dead zone;

Wherein, the step of determining whether the channel to be detected passes the test according to the preset requirements and the actual response signal includes:

Judging whether the output value of the actual response signal is within the preset dead zone interval;

If so, it is determined that the channel to be detected passes the dead zone test;

If not, it is determined that the channel to be detected has not passed the dead zone test.

In this embodiment, for example, the preset dead zone interval is between -0.5V-0.5V, and a signal of 0.4V is sent to the channel to be detected. At this time, if the actual response signal is 0V, then it is determined that the channel to be detected has passed the dead zone. zone test, otherwise it is determined that the channel to be detected has not passed the dead zone test.

In an optional embodiment, the test method of the DCS channel also includes the following steps:

If the actual response signal sent by the channel to be detected in response to the test instruction is not received, it is determined that the channel to the channel to be detected is disconnected.

In this embodiment, the zeroth card in the cabinet can supply power to the equipment in the cabinet, and the first card and the second card respectively transfer the DI signal and the DO signal for output. The third card is an active DI, passive DI, active DO, and passive DO signal type selection card, which is connected to the second card and the third card through hard wiring. The fourth card to the fifteenth card are channel conversion cards. By controlling the conduction of the internal relay of each switch card, the signal input by the third card is selected to be output to each channel to be detected. When it is necessary to collect active DO/passive DO or output active DO/passive DO signal, control the relay in the third card to connect the required signal to the output port. The output end is connected to the input end of the fourth card to the tenth card respectively, and can collect 128 active DO/passive DO signals or output 128 active DO/passive DO signals to the CU.

In an optional embodiment, the step of sending a test instruction to the channel to be detected in the DCS system includes:

In response to the input login information, determine the corresponding test authority;

Send corresponding test instructions to the channel to be tested in the DCS system according to the test authority.

In this embodiment, the input login information includes account number and account password. The logged-in account has security protection functions to ensure that only legally authorized personnel can operate the device.

In the above embodiment, the following steps can also be implemented:

In this embodiment, user rights can be divided into multiple levels. For example, the lowest level user account can only test a certain type of channel to be detected (for example, the channel to be detected is a thermocouple) or a certain test case. .

The above test records can be stored in each table in the database. The names and corresponding functions of each table in the database are shown in the following table:

In the above embodiment, LABVIEW can be selected as the development platform to run the software for the test method of the DCS channel in Embodiment 1, and MySQL can be used as the database server. Realize the data storage, management, display and other functions of the test process and results.

Example 2

Referring to Fig. 6, this embodiment provides a test device for a DCS channel, including:

The sending module 201 is configured to send a test instruction to the channel to be detected in the DCS system; wherein, the test instruction is used to instruct the channel to be detected to send an expected response signal that meets the preset requirements;

The testing module 202 is configured to determine whether the channel to be tested passes the test according to the preset requirements and the actual response signal when receiving the actual response signal sent by the channel to be tested in response to the test instruction.

In an optional embodiment, the testing device of the DCS channel is connected to the channel to be tested through a relay.

In an optional embodiment, in order to ensure that the input/output signal of the test device of the DCS channel, the power supply or the system equipment itself has a problem, the effective grounding can withstand the overload current and can quickly lead the overload current to the ground. Provide a shielding layer for the test device, eliminate electronic noise interference, and provide a common signal reference point (ie, reference zero potential) for the entire control system. When there is a problem in the grounding system (grounding resistance is too large, multi-point grounding, grounding wire is broken or the grounding wire is in contact with high-voltage, high-current equipment, etc.), it will cause electric shock injury to personnel and damage to equipment. Therefore, it is perfect and reliable. , Correct grounding is the key to the safe, reliable and good operation of the test system.

It is a protective measure taken to prevent the accumulation of electrostatic charges on the equipment casing and avoid personal injury. All test devices in this test system (such as CL3001, chassis, etc. in Embodiment 1) should be connected to the protective ground. The test device is connected to the insulator at the bottom of the chassis, one side is connected to the surface of the side cabinet, and the two sides of the insulator are connected with wires, including analog signals or digital signals with weak energy, which are susceptible to power fluctuations or interference from external factors, resulting in The signal-to-noise ratio (SNR) of the signal decreases. Especially for analog signals, the drift of the signal ground will lead to a decrease in the signal-to-noise ratio; the error or error in the measurement value of the signal may lead to the failure of the system design. Therefore, the requirements for the signal ground are relatively high, and special treatment is also required in the system to avoid direct connection with high-power power supply ground, digital ground, and ground wires that are prone to interference. Especially for the measurement of small signals, the signal ground usually needs to adopt isolation technology.

Example 3

This embodiment provides a test system for a DCS channel, including a DCS system and the test device as in Embodiment 2.

Although the specific implementation of the present invention has been described above, those skilled in the art should understand that this is only an example, and the protection scope of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principle and essence of the present invention, but these changes and modifications all fall within the protection scope of the present invention.

Claims (10)

1. The testing method of the DCS channel is characterized by comprising the following steps of:

sending a test instruction to a channel to be detected in the DCS system; the test instruction is used for indicating the channel to be detected to send out an expected response signal meeting preset requirements;

if an actual response signal sent by the channel to be detected in response to the test instruction is received, determining whether the channel to be detected passes the test according to the preset requirement and the actual response signal.

2. The DCS channel test method of claim 1, wherein said predetermined requirement is that the output value of said desired response signal be a predetermined value;

wherein, the step of determining whether the channel to be detected passes the test according to the preset requirement and the actual response signal includes:

judging whether the difference between the preset value and the output value of the actual response signal accords with preset precision;

if yes, determining that the channel to be detected passes the precision test;

if not, determining that the channel to be detected does not pass the precision test.

3. The DCS channel test method of claim 2, further comprising the steps of:

and if the channel to be detected does not pass the precision test, sending a compensation signal to the channel to be detected according to the error precision.

4. The DCS channel test method of claim 1, wherein said predetermined requirement is that the voltage value of said desired response signal is less than a predetermined threshold;

the step of determining whether the channel to be detected passes the test according to the preset requirement and the actual response signal comprises the following steps:

judging whether the voltage value of the actual response signal is smaller than a preset threshold value or not;

if yes, determining that the channel to be detected passes the clamp test;

if not, determining that the channel to be detected does not pass the clamping test.

5. The DCS channel test method of claim 1, wherein said predetermined requirement is that the output value of said desired response signal is within a predetermined dead zone;

the step of determining whether the channel to be detected passes the test according to the preset requirement and the actual response signal comprises the following steps:

judging whether the output value of the actual response signal is positioned in the preset dead zone interval or not;

if yes, determining that the channel to be detected passes the dead zone test;

if not, determining that the channel to be detected does not pass the dead zone test.

6. The DCS channel test method of claim 1, further comprising the steps of:

and if the actual response signal sent by the channel to be detected in response to the test instruction is not received, determining that the channel between the channel to be detected and the channel to be detected is disconnected.

7. The method for testing a DCS channel of any one of claims 1 to 6, wherein the step of sending a test instruction to a channel to be tested in the DCS system comprises:

responding to the input login information, and determining the corresponding test authority;

and sending a corresponding test instruction to a channel to be detected in the DCS according to the test authority.

8. A test device for a DCS channel, comprising:

the sending module is used for sending a test instruction to a channel to be detected in the DCS system; the test instruction is used for indicating the channel to be detected to send out an expected response signal meeting preset requirements;

and the testing module is used for determining whether the channel to be detected passes the test according to the preset requirement and the actual response signal under the condition that the actual response signal sent by the channel to be detected in response to the test instruction is received.

9. The DCS channel test device of claim 8, wherein said DCS system test device is connected to said channel to be tested by a relay.

10. A test system for a DCS channel, comprising a DCS system and a test device for a DCS channel as claimed in claim 8 or 9.

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