JP3176971B2 - Instrumentation system with maintenance function - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an instrumentation system for controlling a system by processing an analog signal from a sensor, and more particularly to an instrumentation system with a maintenance function having a maintenance and inspection function.

[0002]

2. Description of the Related Art Generally, the following two methods are used to calibrate such an instrumentation system.

One is to provide a calibration signal generation circuit in a sensor or a signal processing system, input a calibration signal from an appropriate signal line in the signal processing circuit, and monitor the signal processing output. In this method, calibration is performed by comparing an input calibration signal with a signal processing output, or an operation for calibration is performed by an arithmetic unit of the signal processing system, and the calibration result is displayed and output.

The other is, as shown in FIG. 2, a signal generator having a traceability, that is, a simulated signal generating external device 1 having a function of generating a simulated signal which reproduces an analog signal from a sensor with high accuracy. , A simulation signal is input to the signal processing system 2. And the signal processing system 2
Is monitored by an external instrument 3 connected to the signal processing system 2 from the outside. In this method, the simulated signal generating external device 1 and the external instrument 3
Is controlled by the control computer 4.

[0005] In the above technical means, since the calibration signal generation circuit is included in the control signal processing system, there is an advantage that the calibration signal generation circuit can be controlled by the signal processing system.

However, since the calibration signal generation circuit is incorporated in the signal processing system, there is a limit in generating a simulation signal with high traceability. In addition, the minute analog signal output from the sensor often cannot satisfy the requirements of accuracy and stability unless it is a dedicated meter of a type connected from the outside. Further, the technical means described later satisfies the requirements for accuracy and stability since the external device 1 for generating the simulated signal with high accuracy is used.

However, in order to automatically perform maintenance and inspection of the signal processing system 2, the signal processing system 2
The external instrument 3 for monitoring the output of the
It is necessary to provide a number of outputs corresponding to each of the above, which increases the cost and increases the size of the apparatus.

[0008]

As described above, in the conventional instrumentation system with a maintenance function, when the control of the calibration signal generation circuit is simplified, the accuracy and stability of the simulation signal are reduced and the calibration is highly reliable. In addition, there is a problem that the cost is increased and the size of the apparatus is increased if the calibration accuracy is improved.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides an instrumentation system with a maintenance function capable of realizing highly reliable calibration, reducing costs and miniaturizing the apparatus. Aim.

[0010]

In order to achieve the above object, the present invention provides an instrumentation system in which one or more types of input signals are input to a signal processing unit to obtain predetermined measurement data. A calibration signal generating means provided outside the unit and for inputting a calibration signal to the signal processing unit based on a first control signal given from the outside ; and one or more calibration signal generation means provided inside the signal processing unit.
Measurement signal output and calibration signal output for several types of input signals
Switching between maintenance for input and output of inspection data
Means, and maintenance / inspection data provided in the signal processing unit for the calibration signal of the signal processing unit.
A transmission means for transmitting the output of the calibration signal to the outside based on a second control signal supplied from the outside, and the calibration signal generation means, and the signal processing unit is connected to the signal processing unit via the transmission means. Applying the first control signal to a signal generating means to generate a calibration signal;
Giving the second control signal to the transmission means,
Steps for maintenance of calibration signal input and output of inspection data
And a control computer for collecting maintenance and inspection data from the signal processing unit .

[0011]

According to the present invention, by taking the above-described means, a first control signal is supplied from the control computer to the calibration signal generating means, and the calibration signal is input to the signal processing unit. Then, a second control signal is given from the control computer to the signal processing unit via the transmission means. As a result, the result signal obtained by processing the calibration signal is transmitted again to the control computer via the transmission means, and the maintenance and inspection data is collected by the control computer.

Therefore, since the calibration signal generation means is externally connected to the signal processing unit, a dedicated instrument having high traceability can be used as the calibration signal generation means. In addition, since the measurement data is sent to the control computer via the transmission means provided in the signal processing unit, each type of output of the signal processing unit can be easily taken out by one transmission means, and the output of the signal processing unit can be easily obtained. It is no longer necessary to provide external instruments according to the number of outputs.

[0013]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an instrumentation system with a maintenance function according to one embodiment of the present invention. In the instrumentation system of the present embodiment, a signal processing result (measurement data) of the entire system or a predetermined area is provided at an output stage of a signal processing unit 10 which controls the system by inputting an analog signal from a sensor.
Is connected. Also, a simulated signal generating external device 12 is provided at the input stage of the signal processing unit 10.
And a control computer 14 for controlling maintenance and inspection operations is connected to a transmission interface 13 provided in the signal processing unit 10.

The signal processing unit 10 has an analog input section 15 for performing analog processing such as operational amplification on an analog signal input from a sensor. The signal output from the analog input unit 15 is output to the digital operation unit 1.
6, where measurement data is obtained and a control signal for system control is generated. Further, the digital operation unit 16 has a function of measuring the characteristics of the sensor from the output of the analog input unit 15. The measurement data and the characteristic data are displayed on the display device 11 via the switching circuit 17. The control signal for system control is used for controlling the system. The switching circuit 17 includes the signal processing unit 10
It is configured to be able to selectively extract various data including measurement data and characteristic data.

The simulated signal generating external device 12 is connected to a predetermined signal line to which an analog signal from a sensor of the signal processing unit 10 is input. The simulation signal generation external device 12 is composed of a pulse / function generator and has a function of generating a rectangular wave or a sine wave simulating an analog signal from a sensor. Then, it receives the first control signal from the control computer 14 and operates to input a predetermined simulation signal to the signal line.

The transmission interface 13 includes a transmission / reception unit 13a for transmitting / receiving signals to / from the control computer 14,
A calibration control unit 13b that receives a second control signal from the control computer 14 and controls switching of the switching circuit 17;
Is switched to the transmission interface 13 side, a predetermined processing output of the signal processing unit 10 (measurement data,
And a calibration output unit 13c for outputting the characteristic data) to the control computer 14.

The control computer 14 includes the signal processing unit 1
0 and transmission interfaces 18a and 18b for transmitting and receiving to and from the simulated signal generating external device 12. It has a function of collecting measurement data and characteristic data from the signal processing unit 10 and calculating input / output characteristics (calibration data) of the sensor. The calibration operation of the present embodiment configured as described above will be described below.

First, a first control signal is supplied from the control computer 14 to the simulation signal generating external device 12, and a calibration signal simulating an analog output signal of a specific sensor is sent from a signal line of the sensor to a signal processing unit. 10 is input.

The calibration signal reaches the switching circuit 17 via a normal processing path. Here, during a normal measurement operation, the information is displayed on the display device 11 via the switching circuit 17. on the other hand,
During the calibration operation, the control computer 1
4 outputs a second control signal to the calibration control unit 13b,
The switching circuit 17 is switched to the calibration output section 13c. Therefore, a signal resulting from processing the calibration signal is transmitted from the calibration output unit 13c to the control computer 14 via the switching circuit 13c.

The control computer 14 sends the calibration control unit 1
By giving the second control signal to 3b, the sensor characteristic data calculated by the signal processing unit 10 can be collected from the calibration output unit 13c to the control computer 14.

The control computer 14 calculates the input / output characteristics of the signal processing unit 10 from the measurement data transmitted from the signal processing unit 10 via the transmission interface 13 to calculate calibration data. Edit on the control computer 14. Then, if necessary, the edited result of the output characteristics of the sensor and the input / output characteristics of the signal processing unit 10 is output as a hard copy.

As described above, according to the present embodiment, the signal processing unit 10 is provided with the switching circuit 17 for selectively taking out a plurality of types of processing result signals of the signal processing unit 10, and the selected output is sent to the control computer 14. Since the transmission interface 13 for transmission is provided, it is possible to collect a result signal on an arbitrary signal path without providing an external instrument corresponding to the number of outputs of the signal processing unit, thereby reducing the size and cost of the apparatus. be able to. Moreover, since the simulated signal generating external device 12 is externally connected to the signal processing unit 10, a dedicated device with high precision can be used, and the reliability of the device can be improved.

[0024]

As described above, according to the present invention, it is possible to provide an instrumentation system with a maintenance function that can realize highly reliable calibration, reduce costs and reduce the size of the apparatus.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an instrumentation system with a maintenance function according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a conventional instrumentation system with a maintenance function.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Signal processing unit, 11 ... Display device, 12 ... Simulation signal generation external equipment, 13 ... Transmission interface, 14
... Control computer.

Claims (1)

(57) [Claims] 1. An instrumentation system in which one or more types of input signals are input to a signal processing unit to obtain predetermined measurement data, wherein a first control provided outside the signal processing unit and given from the outside Calibration signal generating means for inputting a calibration signal to the signal processing unit based on a signal , provided in the signal processing unit, one or more types
Output of measurement signal and input of calibration signal for input signal of
Switching means for switching between maintenance and inspection data output
And output of maintenance and inspection data provided in the signal processing unit and for the calibration signal of the signal processing unit.
And are connected via a transmission means for transmitting to the outside based on the second control signal supplied from the outside, the transmission means to the signal processing unit is connected to the calibration signal generation means, the calibration signal generator calibration signal giving the first control signal to means
And the second control is transmitted to the transmission means.
Signal to keep the switching means against the input of the calibration signal.
Switch to the output side of the
And a control computer that collects maintenance and inspection data from the computer.