JPH063464B2 - Multipoint input measuring method and device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention is used for carrying out a method for sequentially switching and measuring a large number of inputs of a large-capacity electric signal requiring high insulation in an electrolytic cell or the like, and for implementing the method. Regarding the device.

[Conventional technology]

In the voltage measurement of a multi-point signal source with a large current capacity and a lot of induced noise, etc., which has a poor SN ratio, in a conventionally known electrolytic cell,
The measurement is generally performed by a combination of an insulation circuit including a switching element such as a relay and a capacitor and an insulation type measurement amplifier.

The second example of the device used for this conventional multi-point input measurement
This will be described with reference to the circuit shown in the figure.

In FIG. 2, 1-1, 1'-1, 1-2, 1'-2, ...
... 1-n, 1'-n are input terminals, 2-1, 2'-1, 2
-2, 2'-2, ... 2-n, 2'-n are security fuses 3-1, 3'-1, 3-2, 3'-2, ... 3
-N, 3'-n are input switching relay contacts, 4, 4 are high frequency noise cutting coils, 5 is a capacitor, 7 is a discharging relay contact, 11 is the above-mentioned relay contacts 3-1, 3'-1,
A sequence control circuit for controlling 3-2, 3'-2, ... 3-n, 3'-n and 7, 8 is a discharging resistor, and 10 is a measuring amplifier.

Thus, one of the input switching relay contacts, for example, 3-1
When 3'-1 is turned on, a signal current flows from the signal input terminal 1 as shown by an arrow →, the capacitor 5 is charged through the high frequency noise cutting coil 4, and the voltage across the capacitor 5 is used as a signal voltage by the measuring amplifier 10. To be measured.

Next, the input switching relay contact 3-1 which was ON,
3'-1 is turned off, the circuit is cut off from the signal source,
After the discharge relay contact 7 is temporarily turned on to discharge the capacitor 5 through the resistor 8, the input switching relay contact of the next signal source, for example, 3-2, 3'-2 is turned on and the signal voltage is measured. The voltage of the signal source is sequentially measured.

In this conventional multi-point input measurement, input switching relay contacts 3-1, 3'-1, 3-2, 3'-2, ... 3-
A rush current (inrush current) flows to the n, 3'-n contacts each time it is turned on and off. For this reason, a general-purpose small contact relay or the like has input switching relay contacts 3-1,
3'-1, 3-2, 3'-2, ... 3-n, 3'-n
Since it was necessary to install a large number of expensive large capacity relays such as mercury relays according to the number of measurement points,
There is a problem that the device becomes too expensive and uneconomical.

This applies not only to the case where the input switching switch is the relay as described above, but also to the case where it is a non-contact type switching element such as a thyristor.
There is a risk that switching elements such as thyristors may be damaged by the rush current at the time of FF, so that there is a disadvantage that many expensive and large-capacity switching elements must be used.

[Problems to be solved by the invention]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems in the conventional method and to provide a novel method with a cost-effective, economical and simple apparatus for multipoint input measurement.

[Means for solving problems]

Therefore, in order to achieve the above object, the feature of the present invention resides in that in the multi-point input measurement using the above-described capacitor charging type insulation circuit, the capacitor charging circuit for charging the capacitor is used. While the switching element is inserted in series, during the charging operation of the capacitor, the input switching switching element is turned on first with the capacitor charging switching element turned off according to the preset program, and then the input switching switching element is turned on. In this ON state, the switching device for charging the capacitor is turned on to charge the capacitor, and after the completion of charging, these switching devices are operated in sequence so that the switching device for input switching is turned off. Is substantially the same as the capacitor charging switch In point configured to perform only by quenching element.

[Action]

By configuring as above, no current flows through the switching element for input switching when it is turned on and off, and the consumption load due to rush current is exclusively for this capacitor charging when switching the switching element for capacitor charging. Since the switching element will be borne, and therefore a large-capacity switching element will suffice with only this one capacitor charging switching element,
It is possible to provide an economical and miniaturizable multipoint input measuring method and apparatus.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is an explanatory view showing an embodiment of a multipoint input measuring device according to the present invention.

In FIG. 1, 1-1, 1'-1, 1-2, 1'-2, ...
... 1-n, 1'-n are input terminals, 2-1, 2'-1, 2
-2, 2'-2, ... 2-n, 2'-n are security fuses 3-1, 3'-1, 3-2, 3'-2, ... 3
-N, 3'-n are input switching relay contacts, 4 and 4 are high frequency noise cutting coils, 5 is a capacitor, 6 is a charging relay contact, 7 is a discharging relay contact, 8 is a discharging resistor, and 9 is A measurement relay contact, 10 is a measurement amplifier, and 12 is a sequence controller for each of the above relays.

Thus, for example, when the input switching relay contacts 3-1 and 3'-1 are turned on, the signal inputs to the input terminals 1-1 and 1'-1 are the security fuses 2-1, 2'-1, and the input switching. The current is not passed through these circuits while the capacitor charging relay contact 6 is turned off though it is guided to the capacitor 5 through the relay contacts 3-1, 3'-1 and the high frequency noise cutting coil 4, but the charging relay When the contact 6 is turned on, the capacitor 5 is charged through the above circuit.

Measurement relay contact 9 is a circuit and measurement amplifier 10 only during measurement
Connect. In other words, the measurement relay contact 9 is fully charged with the capacitor 5, and the input switching relay contact 3-
After 1 and 3'-1 are turned off, they are turned on, whereby the charging voltage of the capacitor 5 is measured. However, this measurement relay contact 9 is not essential, and a measurement amplifier is used.
It can be omitted if 10 is a high input impedance such as an insulation type.

The discharging resistor 8 and the discharging relay contact 7 are for discharging the capacitor 5 as in the conventional method, and are turned on after the measurement of the charging voltage of the capacitor 5 is completed, and the charge of the capacitor 5 is discharged.

Thus, these input switching relay contacts 3-1, 3'-
1, 3-2, 3'-2, ... 3-n, 3'-n, charging relay contact 6, discharging relay contact 7, and measuring relay contact 9 are all sequenced by the controller 12. Controlled.

Next, the operation of the circuit will be described.

First, all relays are initially in the OFF state.

When the measurement is started, the input switching relay contacts 3-1 and 3'-1 connected to the input terminals 1-1 and 1'-1, for example, are first turned on by the setting program of the sequence controller 12, but at this time, the circuit All the other relays are OFF, and no current flows through the input switching relay contacts 3-1 and 3'-1. Therefore, the above-mentioned problem of rush current does not occur at all.

Next, the capacitor charging relay contact 6 connected in series to the capacitor 5 is turned on to charge the capacitor 5, and after charging is completed, the input switching relay contacts 3-1 and 3'-
Set 1 to OFF. At this time, since the input-side and output-side terminals of the input switching relay contacts 3-1 and 3'-1 have the same potential, the input switching relay contact 3-1 and
No electrical load is applied to the 3'-1 contacts.

Next, turn on the measurement relay contact 9 to turn on the measurement amplifier 10.
To measure the capacitor voltage, that is, the input voltage. At this point, the measurement amplifier 10 is already insulated from the signal input side, so that the measurement amplifier 10 can be used in either a non-insulation type or an insulation type.

When the measurement is completed, turn off the measurement relay contact 9 and then
The discharge relay contact 7 is turned on, and the charge of the capacitor 5 is discharged through the discharge resistor 8.

After discharging, turn off all relays and set the next input terminal 1-
2, the measurement cycle is moved to 1'-2, and the measurement cycle operation is sequentially repeated to the input terminals 1-n, 1'-n.

The above measurement cycle operation is repeated according to the setting program of the sequence controller 12 to perform measurement.

It should be noted that the configuration of the present invention is not limited to the above embodiment, and for example, in the above embodiment, relays were used for all switching elements, but these are all replaced with switching elements such as thyristors and SCRs. It is also possible to insert the switching element 6 for charging the capacitor, not limited to the position shown in the figure, as long as it is in the charging circuit of the capacitor, and other circuit configurations are also freely within the scope of the present invention. The design can be changed, and the present invention includes all of them.

〔The invention's effect〕

Since the present invention is configured as described above, according to the present invention, a single large-capacity switching element such as a conventional expensive mercury relay is sufficient, and a general-purpose small switching element or the like is used as an input switching switching element. It is possible to provide a novel multi-point input measuring method and device which is economical and simple, which can reduce the cost and the size and weight of the switching element because the small-capacity switching element can be used.

In addition, an insulating amplifier has been conventionally required as a measuring amplifier, but either an insulating type or a non-insulating type can be used in the method of the present invention.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an embodiment of a multipoint input measuring device according to the present invention, and FIG. 2 is an explanatory diagram showing an example of a circuit of a device used for conventional multipoint input measuring. 1-1, 1'-1, 1-2, 1'-2, ... 1-n, 1'-n ... Input terminals 2-1, 2'-1, 2-2, 2'- 2, ... 2-n, 2'-n ..... Security fuses 3-1, 3'-1, 3-2, 3'-2, .... 3-n, 3'-n .... … Input switching relay contacts 4, 4 …………… High frequency noise cutting coil 5 ………………… Capacitor 6 ………………… Charging relay contact 7 ………………… Discharge Relay contact 8 …………………… Discharge resistor 9 …………………… Measurement relay contact 10 …………………… Measurement amplifier 11 …………………… Sequence control circuit 12 …… …………… Sequence controller

Claims (2)

[Claims] 1. A capacitor (5), a plurality of input switching switching elements (3) for sequentially connecting the capacitors to a large number of signal sources to be measured, and at least one resistor (8) and a capacitor discharge. A capacitor discharge circuit consisting of a switching element (7) for connection to the capacitor, and a device capable of measuring the voltage of the capacitor,
In the method of sequentially measuring a large number of signal inputs using the device (12) for controlling the operation of each of the above components, a switching device (6) for charging the capacitor is provided in the charging circuit of the capacitor (5). While inserting in series, during the charging operation of the capacitor (5), according to a preset program, first the switching element for capacitor charging (6) is turned off and the switching element for input switching
Turn on (3), then switching element for input switching (3)
In this ON state, the switching device (6) for charging the capacitor is turned on to charge the capacitor (5), and the switching device (3, 6) for switching the input is switched off after the charging is completed. A multi-point input measuring method, which is characterized by operating in sequence. 2. A capacitor (5), a plurality of input switching switching elements (3) for sequentially connecting the capacitors to a large number of signal sources to be measured, and at least one resistor (8) and a capacitor discharge. A capacitor discharge circuit consisting of a switching element (7) for connection to the capacitor, and a device capable of measuring the voltage of the capacitor,
In a device for sequentially measuring a large number of signal inputs using the device (12) for controlling the operation of each of the above components, a capacitor charging switching device (6) is provided in the charging circuit of the capacitor (5). While inserting in series, the control device (12), during the charging operation of the capacitor (5),
First, the input switching switching element (3) is turned on while the capacitor charging switching element (6) is turned off, and then the input switching switching element (3) is turned on and the capacitor charging switching element is turned on.
(6) is turned on to charge the capacitor (5), and a program is set to operate these switching elements (3, 6) in sequence in order to turn off the input switching switching element (3) after charging is completed. A multipoint input measuring device characterized by comprising: