JP5479288B2 - Instrumentation system - Google Patents

Description

  Embodiments of the present invention relate to an instrumentation system.

  Conventionally, a plurality of measuring instruments for monitoring and control are installed in an industrial plant, and a wired cable is laid between these measuring instruments and a control device, and a measurement signal from the measuring instrument is transmitted to the control device. Thus, monitoring and control of industrial plants have been performed. However, in recent years, a wireless system is being adopted in which a wired cable is omitted and signal transmission is performed using radio waves for the purpose of rationalizing the construction work cost and the construction period. In order to fully enjoy the merits of this wireless method, it is necessary to review the power supply method.

  That is, conventionally, the control device supplies power to the measurement instrument through a wired cable. However, the wireless system is configured to supply power by incorporating a battery in the measurement instrument. The problem here is the battery life, and it is necessary to systematically replace the battery (or charge the battery to the battery) before the battery life is exhausted. Monitoring and control will be interrupted.

  In addition, normally, among measuring instruments used in industrial plants, those that make the continuous operation of the plant extremely difficult when the instrument fails are handled as important measuring instruments, which makes redundancy in instrumentation system design redundant. Is planned. For example, the measurement instrument used for main control is duplicated (two instruments are installed), and when one instrument fails in the control device, the signal is sent to the other healthy instrument. Measures such as line switching are performed, and it is planned that there is no hindrance to continuation of control even if one instrument fails.

  In addition, the measurement instrument related to the protection function that is more important is tripled (three instruments are installed), and the intermediate value selection of three measurement values and 2 out of 3 processing are performed in the control device. Thus, even if one instrument breaks down, it is planned that the protection function is not hindered by two healthy instruments. In this way, even if one measuring instrument is lost, a redundant design that maintains control and protection functions and continues operation of the plant is adopted. When adopting redundancy as described above, it is a general rule that measurement instruments have the same design (same specifications, same model) and are duplicated or tripled.

JP 2007-67829 A

  However, when a measuring instrument with a battery built in the instrument is duplicated or tripled by the wireless method as described above, the following problems may occur if the same battery is used in each measuring instrument. For example, the battery life of two or three measuring instruments may be exhausted at the same time, and control and protection functions will be lost and the plant will continue to operate despite the redundant installation of the instruments themselves. May become impossible.

  It is also conceivable to manage the battery life, to estimate the timing before the designed battery life is exhausted, and to sequentially replace the batteries (or charge the battery to the battery) for each redundantly installed instrument. However, the design battery life has an error, and there is no denying the risk that the battery life will be exhausted before the battery replacement is scheduled.

  The present invention has been made in order to solve the above-described problems of the prior art, and an object of the present invention is to provide an instrumentation capable of preventing the battery life included in each of the redundant measuring instruments from being exhausted at the same time. To provide a system.

In order to solve the above-described problems, the instrumentation system of the first embodiment includes a battery, and in the instrumentation system in which measurement instruments that operate by receiving power supply from the battery are multiplexed and installed, the multiplexing and installation are performed. The design life of the batteries incorporated in each of the measured measuring instruments is different from each other. More specifically, the design life of each battery has a prime relationship with each other.

It is a figure which shows the structure of the instrumentation system of Example 1. FIG. It is a figure which shows the structure of the instrumentation system of Example 2. FIG.

  Hereinafter, an embodiment of an instrumentation system and a battery life setting method in the instrumentation system according to the present invention will be described with reference to the drawings.

(1-1) Configuration of Example 1 FIG. 1 shows an example of an instrumentation system according to the present example and a battery life setting method in the instrumentation system. That is, in FIG. 1, the tank 1 forms a part of an industrial plant, and it is essential for the operation of this industrial plant to maintain this internal pressure appropriately. Therefore, the tank 1 is provided with a first measuring instrument 2 and a second measuring instrument 3 which are made redundant (here, duplicated).

  The first measuring instrument 2 is provided with a first wireless transmitter 4 and a first battery 7, and the second measuring instrument 3 is provided with a second wireless transmitter 5 and a second battery 7. A battery 8 is installed. The batteries 7 and 8 are configured so that power is supplied to each of the first measuring instrument 2 and the second measuring instrument 3. The batteries 7 and 8 need to be replaced (or charged to the battery) when a certain battery life is reached.

  In this case, in this embodiment, the design battery lifetimes of the first battery 7 and the second battery 8 have a relatively prime relationship of 13 months and 17 months, respectively. Here, “a coprime relationship” means that the greatest common divisor of the lifetime of two batteries is 1. By designing in this way, there is a difference of 4 months between the lifespans of both batteries, so even if there is an error in the design battery life, the battery life of the two measuring instruments 2 and 3 may run out simultaneously. Can be virtually eliminated.

  The dual measuring instruments 2 and 3 equipped with the batteries 7 and 8 as described above both measure the internal pressure of the tank 1, and the radio transmitter 4 installed in each measuring instrument 2 and 3 receives the measurement signal. 5 to the control device 6 wirelessly. The control device 6 is configured so as to receive these measurement signals and to control the inside of the tank 1 at an appropriate pressure by a control circuit or a control valve (not shown).

  In this embodiment, for example, when one of the duplicated measuring instruments fails, the control device 6 is switched to use a measurement signal transmitted from the other healthy measuring instrument by a switching circuit (not shown). This is done so that there is no hindrance to the continuous operation of the plant.

(1-2) Operation and Effect of Example 1 In the present example having the above-described configuration, the design battery life of the first battery 7 and the second battery 8 is 13 months and 17 months, respectively. Since they are in a coprime relationship, it is possible to prevent the battery replacement timings of the first battery 7 and the second battery 8 from occurring at the same time. That is, in practice, maintenance personnel manage and record the time for battery replacement to replace the battery before the end of the battery life. In this case, for example, the first battery 7 and the second battery are replaced. If the battery life of the battery 8 is 10 months and 15 months, respectively, the life of both batteries will be exhausted at the 30th month which is a common multiple.

  On the other hand, as in this embodiment, the battery life of the first battery 7 and the second battery 8 is 13 months and 17 months, respectively. It becomes possible to set the time in the very far future of the 221th month (= 13 × 17).

(1-3) Modification of Embodiment 1 In this embodiment as described above, the battery voltage of one instrument is transmitted by wirelessly transmitting the battery voltage of each measuring instrument to the control device and monitoring each battery voltage. However, when it is detected that the battery voltage of the other instrument has significantly decreased, it is possible to manage the replacement time of each battery by determining that the battery life has expired.

(2-1) Configuration of Example 2 This example is a modification of Example 1 and shows a case where the measuring instrument is tripled. That is, as shown in FIG. 2, the tank 9 forms a part of an industrial plant, and when the internal pressure deviates greatly from an appropriate value, it is necessary to stop the operation of the industrial plant. To do. Therefore, the tank 9 is provided with a redundant first measuring instrument 10, second measuring instrument 11, and third measuring instrument 12.

  The first measuring instrument 10 is provided with a first wireless transmitter 13 and a first battery 17, and the second measuring instrument 11 is provided with a second wireless transmitter 14 and a second battery 18. The third measuring instrument 12 is provided with a third wireless transmission device 15 and a third battery 19. These batteries 17, 18, 19 are configured to supply power to the first measuring instrument 10, the second measuring instrument 11, and the third measuring instrument 12.

  These tripled measuring instruments 10, 11, and 12 measure the internal pressure of the tank 9, and transmit the measurement signal to the control device 16 wirelessly via the wireless transmitters 13, 14, and 15. . And the control apparatus 16 receives these measurement signals, and when the intermediate value selection process of a measurement signal is performed by the protection circuit which is not shown in figure, and it detects that the value deviated from the appropriate value largely, a plant operation will be stopped. It is configured as follows.

  In this case, in this embodiment, the design battery lifetimes of the first battery 17, the second battery 18 and the third battery 19 are relatively prime, 3 years, 5 years and 7 years, respectively. It is said that. By designing in this way, it is possible to prevent two of the three batteries from being replaced at the same time. That is, there is a difference of two years in the life of each battery, so even if there is an error in the design battery life, two measuring instruments can virtually eliminate the possibility that the battery life will run out at the same time. it can.

  In the present embodiment, for example, when the first measuring instrument 10 fails, since the intermediate value selection is given, based on two normal measurement signals of the measuring instrument 11 and the measuring instrument 12 It is planned to be monitored and controlled so that the protection function is not hindered.

(2-2) Operation and Effect of Example 2 In the present example having the above-described configuration, the design battery life of the first battery 17, the second battery 18, and the third battery 19 is as follows. Since the three-year, five-year, and seven-year relationships are relatively prime, it is possible to prevent the two batteries from being replaced at the same time among the three batteries. In other words, in practice, maintenance personnel manage and record the time for battery replacement to replace the battery before the end of the battery life. In this case, for example, the first battery 17 and the second battery When the battery lifetimes of the battery 18 and the third battery 19 are 2 years, 4 years, and 6 years, respectively, the lifetimes of the first battery 17 and the second battery 18 are exhausted at the same time in the fourth year, which is a common multiple. Things happen.

  On the other hand, as in the present embodiment, the battery life of the first battery 17, the second battery 18, and the third battery 19 is assumed to be a relatively prime relationship of 3 years, 5 years, and 7 years, respectively. Thus, it is possible to set the shortest time when the lifetimes of the two batteries are exhausted at the very far future of the 15th year.

(2-3) Modification of Embodiment 2 In this embodiment as described above, the battery voltage of each measuring instrument is wirelessly transmitted to the control device, and the battery voltage of one instrument is monitored by monitoring each battery voltage. When it is detected that the voltage has significantly decreased with respect to the battery voltages of the remaining two meters, it is possible to manage the replacement time of each battery by determining that the life of the battery has been exhausted.

  As described above, some examples of the present invention have been described in the present specification. However, these examples are presented as examples and are intended to limit the scope of the invention. Not. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These examples and modifications thereof are included in the scope of the invention and the gist thereof, and are also included in the invention described in the claims and the equivalent scope thereof.

DESCRIPTION OF SYMBOLS 1 ... Tank 2 ... 1st measuring instrument 3 ... 2nd measuring instrument 4 ... 1st radio | wireless transmitter 5 ... 2nd radio transmitter 6 ... Control apparatus 7 ... 1st battery 8 ... 2nd battery 9 DESCRIPTION OF SYMBOLS ... Tank 10 ... 1st measuring instrument 11 ... 2nd measuring instrument 12 ... 3rd measuring instrument 13 ... 1st wireless transmitter 14 ... 2nd wireless transmitter 15 ... 3rd wireless transmitter 16 ... Control Device 17 ... first battery 18 ... second battery 19 ... third battery

Claims (2)

In an instrumentation system that has a built-in battery and multiplexes and installs measurement instruments that operate by receiving power from the battery
An instrumentation system characterized in that design lifetimes of batteries built in each of the measurement instruments installed in a multiplexed manner are different from each other. 2. The instrumentation system according to claim 1, wherein a design life of a battery built in each of the measurement instruments installed in a multiplexed manner is a coprime relationship.

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