JPS633257A - System controller for multiwavelength uv detector control - Google Patents

Abstract

PURPOSE:To automate system operation by a simple system without the intervention of a host external computer by providing a multiwavelength UV detector to one of plural unit devices of an instrument for analysis and bringing signals among the devices under the control of a system controller. CONSTITUTION:The system controller SC is provided which controls the plural unit devices constituting the instrument for analysis of liquid chromatography. The controller SC is equipped with a CPU and a communication interface 5 for transferring signals among the unit devices. Further, the controller SC and the multiwavelength UV detector MUV of one unit device are connected by a BUS through interfaces 5 and 5. The controller SC sends instructions of wavelength, auto-zero mode, a marker, a range, the number of times of integration, and spectrum width as control items of a measurement condition to the detector MUV. At this time, both of them are allowed to have mutual communication, the measurement condition is set, and the setting is monitored. Thus, control is performed through the mutual communication between the system controller and multiwavelength MUV detector, so the instrument for analysis is automated efficiently.

Description

[Detailed Description of the Invention] Yuri Dansako (Field of Industrial Application) The present invention relates to a system controller used to control an automatic analysis system, and in particular to a system controller used to control an automatic analysis system, and in particular to a system controller used to control an automatic analysis system. This is a system that controls and operates analytical instruments while transmitting signals, and is related to a system controller that automatically controls a multi-wavelength UV detector.

(Prior art) Analytical instruments, such as high performance liquid chromatograph (HPLC)
The system includes a pump to deliver liquid as a mobile phase at high pressure, a preparative/injection device to separate the required amount of the sample to be analyzed and inject it into the mobile phase, and a column. A detection device such as a visible/ultraviolet absorption photometer to detect substances in the mobile phase that has flowed out, a constant temperature bath to maintain the sample in the preparative/injection device at a constant temperature, or a thermostat to record the detection signal. It has a configuration that combines a large number of devices (unit devices) such as recorders.

Recently, however, there has been a growing demand for automated analysis operations in analytical instruments such as high-performance liquid chromatographs. Autosamplers that perform fractionation and injection have been developed. Furthermore, recently there has been a demand for full automation of the entire operation of analytical instruments such as high-performance liquid chromatographs.

The present applicant has previously discovered that in various analytical instruments such as high-performance liquid chromatographs, there are multiple unit devices that make up the analytical instruments, such as liquid pumps, autosamplers, thermostats, detectors, and even system controllers. We proposed a device suitable for transmitting signals between unit devices for controlling the operation of each unit device and for data transfer, but in such an HPLC system, UV
(visible ultraviolet) detectors are used, and recently, HP has introduced multi-wavelength UV detectors that can obtain a large amount of information in one analysis.
It is becoming important as a detector for LC. However, conventional multi-wavelength UV detectors used as unit devices in such automatic analysis systems can generally only be automatically controlled from a host external computer (personal computer) connected to them. Although the multi-wavelength UV detector in the - section could operate without an external computer, measurement parameters such as wavelength, auto-zero, start marker, detection limit, data integration number, etc. could only be set by its own key human power; Linking with unit equipment,
Controls such as auto-zero, which shifts the baseline of the detector to the zero point immediately before injection, were not possible.

(Problems to be Solved by the Invention) Therefore, an object of the present invention is to provide a multi-wavelength UV detector in a cheaper manner using a hour wheel than in the past, without using a host external computer.
The object of the present invention is to provide a system controller that can be connected to a molecular system controller such as a PLC for analysis, obtain a large amount of analysis information, and fully automate system operation.

Main System Controller (Means for Solving the Problem) In order to achieve the above object, the system controller according to the present invention transmits signals between a plurality of unit devices constituting an analytical instrument such as a liquid chromatograph. A system controller used to control analytical instruments,
One of the unit devices is a multi-wavelength UV detector, and the system controller is at least a central processing unit (CPU),
It is equipped with a keyboard, a display, a storage device, and an input/output interface for communication, and it is equipped with a multi-wavelength UV light from the keyboard.
The measurement conditions of the detector are entered manually as an analysis program, and the measurement conditions are serially transferred to the multi-wavelength UV detector in the form of commands via the communication input/output interface according to the input and stored analysis program, and mutual communication is performed between the two. This is characterized by setting and monitoring measurement conditions.

The control items for the above measurement conditions include each wavelength, auto zero,
Includes marker, range, number of integrations, and spectral width.

In addition, if an operator touches the device while it is charged (which often happens in dry indoor rooms during the winter in Japan), electrical discharge may occur, which may cause noise and cause malfunctions, detection errors, and data disturbances. In a preferred embodiment of the invention, the system controller and multi-wavelength UV detector are electrically isolated from the system bus for signal communication to prevent noise from being transmitted over the system bus.

(Example) Hereinafter, specific examples of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a block diagram showing the configuration of a system controller according to the present invention. As shown in the figure, the system controller SC includes a central processing unit ff1 (cpU) 1, a keyboard 2 which is a human power device connected to the CPU 1 through a key power interface 6, and an output device connected to the CPU I through a CRT interface 7. A display 3 such as a CRT, and a storage device attached to the CPU
Communication system input/output (, SIO
) comprises an interface 5. The storage device 4 includes a memory (RAM) 8 that stores a system analysis program as a file, and a memory that stores a control program.
(ROM). In the figure, numeral 10 is an oscillator for clock input, and numeral 11 is a power supply for supplying voltages necessary for each part.

The system controller SC configured in this manner is connected to each unit device forming the analysis system through the communication SIO interface 5.

FIG. 2 shows the connection between the multi-wavelength UV detector MUV, which is one of the unit devices and is the object of the present invention, and the system controller SC. Although the specific configuration of the multi-wavelength UV detector MUV is not particularly shown in the figure, it is basically the same as the configuration of the system controller SC shown in FIG. , 5 are connected via a system bus BUS so that they can communicate with each other. In the system controller SC, the measurement conditions of the multi-wavelength UV detector, such as 4 wavelengths, detection sensitivity, number of data integrations, spectrum width, and baseline zero suppression, are inputted interactively to the CRT 3 via the keyboard 2, and the time program Settings are also possible. The program contents are stored in the storage device 4 as a system analysis program file and sent to the multi-wavelength U through the SIO interface 5.
It is serially transferred to the V detector in command format. - Conversely, the operating status of the multi-wavelength UV detector is also returned in the same format and displayed on the SC's CRT3.

Next, system controller SC and multi-wavelength UV detector M
A method of communication between UVs will be explained.

Communication is performed by serial transfer of commands under microcomputer control. An example of the command format is shown in FIG. The parts of the command and their functions are listed below: Ileadder: This specifies the nature of the command. For example, it indicates command transfer, status command, normal transmission/reception confirmation (ACK), abnormal transmission (NACK), etc.

Destination (D, Device): Specify the destination device by code number.

Sender (S, Device): Specify the source device using a code number.

Command; Indicates an instruction. This command varies depending on the device, but for a multi-wavelength UV spectrometer, there are the following commands.

(a) Wavelength setting command (b) Auto zero command (c) Start marker command (d) Status check command (e) Status content command (f) Abnormal reset command Parameters: Some commands have no parameters, some have fixed length 2 with variable length parameters. For example, wavelength data, status code, etc.

C, S: Performs 8-bit addition from the hesodar to the terminator to check whether the communication contents are correct or not. In other words, checksum.

:terminator. Indicates the end of transfer.

Next, an example of a communication procedure using such a command is shown in the fourth section.
As shown in the figure. In the figure, the left side is the system controller SC, the right side is the multi-wavelength UV detection IMUV, and the center is a command format signal that is serially transferred between the two.

For example, when setting the wavelength (four wavelengths λ1 to λ4), the wavelength setting value is entered manually on the system controller side (S1), processed by the CPU (S2), and then sent from the system controller SC to the wavelength setting value. Status check command G
ET 5TATUS uses multi-wavelength UV detector MU at regular intervals.
This is repeated until an ACK is received from MUV (S3). GET when ACK comes 5TATII
Stop S output and prepare to receive status data. In response, the status data content command 5TATUS TRANSFER is returned from the MUV to the SC (
SC). Now run the MUV status check (3
7), the wavelength setting command WLSET is output to the MUV (S8), and the MUV receives this and sets the wavelength (λ1 to λ4).
) are set (S9).

As described above, the wavelength setting, which is one of the measurement conditions for the multi-wavelength UV detector, is established through communication between the two parties, and as is clear from Figure 4, transmission and reception involve the exchange of ACK and NACK. Proceed while checking whether the equipment is normal or abnormal and the status of each other. In general, the following six control items regarding the measurement conditions of a multi-wavelength UV detector can be programmed and controlled from the system controller, including wavelength settings:
(1) Wavelength: (4 wavelengths: λ1.λ2.λ3.λ4) (
2) All TOZERO: Shift the baseline of absorption measurement data to the zero point.

(3) MARKER: Timing signal for sample injection (4) RANGE: Detection sensitivity, can be set independently for each wavelength (5) Number of integration: Number of data integration (6) Spectral width: Half width of wavelength , a more specific block configuration of the hardware for implementing communication is shown in FIG. The key input from the keyboard 2 is transferred to the SIO interface 5 through processing by the CPUI, and after being converted into serial data,
The first photo isolator 14 is operated by the first buffer 12.
and is transmitted via the output signal line in the system bus Bus (SIG 0UT). The receiving side is configured in exactly the same manner, and the received signal SIG IN enters the 310 interface 5 through the second photo isolator 15, is converted into parallel data, and is then sent to the CPU 1 for processing.

Note that the SIO interface and the system bus are isolated by an independent power supply 16 and a photo-isolator.

In the above embodiment, the multi-wavelength U used in the HPLC system
Although the system controller for controlling the V detector has been explained, it is also possible to use multi-wavelength UV as a unit device in other systems.
The present invention is also applicable to various analytical instruments in which detectors are used.

(Effects of the Invention) Abnormalities As stated above, according to the present invention, a system controller can be obtained which can control a multi-wavelength UV detector without using a host external computer and by a method that is simpler and cheaper than using an external computer. Analytical aliquot system mobilization such as HPLC can be carried out even more efficiently. In other words, since an external computer is not used, it is easy to link units, and it is also possible to automatically apply auto-zero just before injection.Furthermore, since a time program can be set for each wavelength, the detection wavelength can be adjusted for each peak. It is also possible to change.

Of course, control by an external computer is also possible. -Generally, when both are connected, priority is given to external computer control, but it may be the other way around, or selection may be made with a switch.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing the configuration of the system controller according to the present invention, Fig. 2 is a diagram showing the connection relationship between the system controller and the multi-wavelength UV detector, and Fig. 3 shows the format of commands used in communication between the two. FIG. 4 is a diagram showing an example of a communication procedure between the two, and FIG. 5 is a diagram showing an example of a specific hardware configuration for communicating between the two. SC...System controller, MUV...Multi-wavelength UV detector, BUS...System path, 1...
Central processing unit (CPU), 2...Keyboard, 3
... Display (CRT), 4... Storage device, 5... Communication input/output (SIO) interface,
14.15...Photo isolator.

Claims (3)

[Claims] (1) A system controller used to control an analytical instrument while transmitting signals between multiple unit devices that make up an analytical instrument such as a liquid chromatograph, one of which is a multi-wavelength UV detector. A system controller for controlling a multi-wavelength UV detector, characterized in that measurement conditions are set and monitored through mutual communication between the two. (2) The control items for the above measurement conditions are each wavelength, auto zero,
The system controller according to claim 1, characterized in that the system controller includes a marker, a range, a number of integration times, and a spectrum width. (3) The system controller according to claim 1, wherein the system controller and the multi-wavelength UV detector are electrically isolated from a system bus for signal communication.