JPH0718857B2 - Controller with program for liquid chromatograph system protection - Google Patents

Description

The present invention relates to a controller having a program for system protection of a liquid chromatograph, and in particular, when trouble occurs, various kinds of appropriate measures can be taken according to the situation at that time. The present invention relates to a controller having a system protection program.

2. Related Art Liquid chromatograph (hereinafter abbreviated as LC) system configurations are roughly divided into two. One is a dedicated machine with a specific purpose, and the other is a combination of component types with no particular restrictions.

The purpose of the special-purpose machine represented by an amino acid analyzer is naturally limited, but since the movement of each unit such as the solvent switching valve, liquid transfer pump, oven, reaction tank, and detector is fixed, fine control is possible. is there. Even in an actual device, various sensors are built in to detect troubles that cannot be done with the component type. However, the actual situation is that nothing is done about the control after the occurrence of trouble. That is, when a trouble occurs, all the functions are stopped or only the function where the trouble is generated is stopped.

On the other hand, the center of control in the combination of component types is what is called a system controller. Normally, this system controller controls each of the above units. When a trouble occurs in a certain unit, the signal is transmitted to the controller, and the controller performs necessary control. However, when trouble occurs in a unit under the control of the system controller, even if the unit is naturally stopped, it is not possible to finely control the operation of other units. In other words, the other units either continue to operate as they are, or all of them including the trouble occurrence unit are stopped.

Problems to be Solved by the Invention The conventional control as described above has the following disadvantages. For example, a reaction chromatograph typified by amino acid analysis has a system in which a plurality of pumps feed liquid. With this configuration, if all pumps stop when trouble occurs, if any pump stops during analysis, the remaining pumps also stop. As a result, the reaction coil is clogged with deposits.

On the other hand, if the system in which only the troubled unit is stopped is used, the above-mentioned deposition in the reaction coil does not occur, but the detector continues to operate and the light source is wasted.

Even in a simpler system, if the pump stops due to a trouble during high-sensitivity analysis, it takes time for the system to recover to a stable state again.

Therefore, an object of the present invention is to provide a controller having a system protection program for a liquid chromatograph capable of performing various appropriate and appropriate measures depending on the situation at the time of occurrence of trouble.

Means for Solving the Problems In order to achieve the above object, a controller having a system protection program according to the present invention has a liquid feed pump, a solution switching valve, an oven, a reaction tank after a trouble occurs in a liquid chromatograph. , The operation of each unit such as detector,
It is possible to separately control by selecting any one of (a) immediate stop of occurrence of trouble; (b) stop after a certain period of time; and (c) operation without stopping.

Further, depending on the type of trouble, each unit is forcibly stopped after the trouble occurs.

More preferably, even if the limiter of the liquid feeding pump is activated and stopped based on the control, the liquid feeding can be continued by changing the flow rate or changing the liquid feeding mode.

In a preferred embodiment, the type of trouble and each unit are displayed in a matrix, and the operator can specify the operation after the trouble occurs by inputting a numerical value.The type of trouble is a pump and an auto sampler, and each unit is a pump. , An oven, a detector, a switching valve and an external device, and it is desirable that the operating time of each unit after a trouble occurs can be arbitrarily set.

Example In the component type combination LC, as shown in FIG. 1, the system controller SC and the illustrated pump 1 (P1), auto sampler, oven (OVEN), detector (UV), and switching valve (VALVE, A) , B & C), pumps 2, 3 (P2,
3), Each unit of LC such as external outlet (AC OUT) is connected by mutual interconnection wiring, and during normal operation, control signals are sent from the controller to each unit via this wiring.

If you have a problem with one of your units,
This is detected by the system controller, and control for system protection is performed. As a method of detecting a trouble, a method in which the unit in which the trouble has occurred notifies the system controller immediately, and a system controller sequentially monitors the state of each unit,
There is a method of detecting during that cycle.

The system controller that has detected the occurrence of a trouble then determines the content of the trouble. If the trouble that occurs is a danger related to safety such as overheating of the oven, immediately stop the operation of all units. On the other hand, in the case of a trouble not related to safety (for example, the overpressure state of the pump 1), refer to the program (here called system protection program) setting built in the controller, The operation is separately controlled according to any one of (a) immediately stopping when trouble occurs; (b) stopping after a certain period of time; and (c) operating as it is without stopping (this specific example will be described later). The following process is shown collectively in the flow chart of FIG.

By the way, it is the best for the purpose of protection of the device and shortening the recovery time to be able to program for all troubles and all units, but the trouble of setting (the number of key operations increases, but more than that) Considering that it takes time to assume the operation of the unit for each trouble), the type of trouble and the number of units to be targeted must be restricted to some extent. Since the restriction facilitates the setting, there is a merit that the operator can easily utilize it.

In the case of LC, pump trouble is one of the most important problems. That is, whether or not the eluent is flowing has a great influence on the protection of the device and the shortening of the recovery time.
The next problem after the pump is the trouble of the auto sampler. Trouble with the detector, data processor, and oven has almost no effect on the protection of the device and shortening the recovery time. Thus, in a preferred embodiment of the present invention,
Trouble used for control is 2 of pump and auto sampler.
Let's make it a kind. Of course, it is of course possible to control for all the troubles that may occur if the trouble of setting is ignored.

Next, considering the units whose operations should be controlled, similar to the types of troubles, if you ignore the trouble of setting, all units may be targeted, but the units that need to be actually processed can be limited, and (P1,2,3), oven (OVEN), detector (UV), switching valve (VALVE, A, B &
C), external outlet (equipment) (AC OUT) is sufficient. Since the data processor and auto sampler are units that do not operate unless there is a sample injection command, it is not necessary to consider the processing in particular. In other words, if trouble occurs, the injection command will not be issued.

These processing units are controlled according to any of the three options as described above. For example, the pump stops the one in which the trouble has occurred, and the rest continues to operate. After the trouble occurs, the oven is kept on for a certain time and then stopped. The detector should be turned off to reduce lamp exhaustion or left on to reduce recovery time. Depending on the case, the switching valve is switched so that the washing solvent flows.

In order to make such settings, in the preferred embodiment, the type of trouble and each unit are displayed in a matrix, and the operator inputs numerical values. A display example of this program format is shown in FIG. The first line in the format is the program name. The safety time on the second line is the set time on the right side of the slash (1), and the unit programmed to stop after a certain time stops after this set time.
The left side of the slash (1) is the elapsed time from the occurrence of trouble, and is counted up until the operator stops the controller by key operation.

Below that is a matrix for inputting numerical values. The type of trouble (pumps 1 to 3 and auto sampler) is in the row direction, and the unit (P1,2,3, OVEN, UV, VALVE,
A, B & C, AC OUT) are arranged side by side in the column direction. The operator inputs a numerical value while moving the cursor.
One concrete input example is shown in FIG. When the pump (P1) has a trouble of overpressure (OVER PRESS), in the example shown in the figure, the liquid feeding mode can be switched without stopping the pump to feed the liquid.

On the other hand, if the pressure is underpressure (UNDER PRESS), stop the pump. Causes of underpressure may be running out of solvent, defective operation of pump head, defective operation of solvent selection valve, etc. Regardless of whether the pump runs dry or air is sent to the column, the system is seriously damaged. May give. Therefore, unlike the case of overpressure, the operation of the pump is disabled.

That is, in the example of FIG. 4, when the pump (P1) has an overpressure, the pump intermittently sends the liquid, the oven stops after 10 minutes of the set safety time, and the UV detector continues to operate. Also, if the pump is underpressure, the pump and oven will shut down immediately and the VU detector will continue to operate.

As a specific example, if a pump is stopped due to overpressure when a solvent that easily precipitates is used, precipitation tends to occur more easily than when the solvent is flowing. In the present invention, the pump is programmable so that it can continue to deliver liquid, so less damage is done to the device.

Further, in reaction chromatography, if the reaction liquid pump continues to operate with the main pump (eluent liquid feeding pump) stopped, the reaction coil may be clogged. In this case, in the present invention, the solvent selection valve can be switched to program the cleaning solution to flow into the reaction solution pump.

Furthermore, it is also possible to perform self-diagnosis after stopping the operation of the unit in which a trouble has occurred.

EFFECTS OF THE INVENTION As described above, according to the present invention, each unit after the occurrence of a trouble was either completely stopped or continued to operate. It can be finely controlled. That is, the operator can program whether to immediately stop in consideration of the loss of the solvent or consumables, or to continue the operation as it is in consideration of shortening the start-up time when restarting. Further, since the type of trouble and the operation of each unit can be designated, there is an advantage that it can be applied to various systems.

[Brief description of drawings]

FIG. 1 is a schematic block diagram showing the configuration of a component type combination LC, FIG. 2 is a flowchart, FIG. 3 is a matrix display format, and FIG. 4 is an input example of the same format. SC: System controller, P1-3, UV, OVEN, VALVE, AC OUT ... Each unit.

Claims (7)

[Claims] 1. After a trouble occurs in a liquid chromatograph, a liquid feed pump, a solution switching valve, an oven, a reaction tank,
The operation of each unit such as the detector can be controlled separately by selecting either (a) immediate stop when trouble occurs; (b) stop after a certain period of time; or (c) continue operation without stop. A controller with a system protection program for the characteristic liquid chromatograph. 2. A controller having a system protection program according to claim 1, wherein each unit is forcibly stopped after the trouble has occurred depending on the kind of the trouble. 3. Even if the limiter of the liquid feed pump operates and stops based on the control, the liquid feed can be continued by changing the flow rate or changing the liquid feed mode. A controller having the system protection program according to the range (1). 4. The system protection program according to claim 1, wherein the type of trouble and each unit are displayed in a matrix, and the operator can specify the operation after the trouble occurs by inputting a numerical value. With a controller. 5. The type of trouble is a pump and an auto sampler, and each unit is a pump, an oven, a detector, a switching valve, and an external device, according to claim (4). A controller with a system protection program. 6. A controller having a system protection program according to claim 1, wherein the operating time of each unit after a trouble has occurred can be arbitrarily set. 7. A controller having a system protection program according to claim 1, wherein self-diagnosis of a unit having a trouble is performed.