JP2003141674A - Multi-channel signal-switching device for measuring- system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a common of a signal not used commonly, to compactify a size, and to reduce a cost. SOLUTION: This switching device is provided with a plurality of relays for switching concurrently a signal line for inputting an analog signal from a measuring object and a reference signal line in each relay circuit, in a plurality of relay circuits, an insulated signal converter connected to the relays, a relay driving circuit for controlling opening and closing timing of the plurality of relays, a measuring and control part for converting the analog signals received from the plurality of relays via the signal converter into digital signals, and for controlling the relay driving circuit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an analog signal switching device having multiple channels, and more particularly to a multi-channel analog signal switching device having one insulating signal converter and having no common signal common.

[0002]

2. Description of the Related Art Conventionally, there has been a signal switching device that obtains analog measurement data signals from a plurality of measurement objects, converts them into digital signals, and supplies them to a signal processing device, a signal display device, and the like. There is.

Some of such devices are configured so that the reference potential (common) of the measurement signal is common and the use of an insulating signal converter is not necessary. However, if the common is used in common, the reference potential may not match the reference potential of the measurement target and may shift depending on the measurement target, so that an accurate voltage may not be measured.
Therefore, there is a device that uses an isolation converter for each channel without making the common common. According to such an apparatus, since the common is not shared, the common can be adjusted to each reference potential for each measurement target, and accurate measurement can be performed.

[0004]

However, the device not having a common common is provided with an isolation converter for each channel so that the difference in reference potential between the channels does not affect the signal processing device or the like. ing. As a result, the device becomes large and the cost increases.

[0005]

SUMMARY OF THE INVENTION Therefore, the present invention provides a multi-channel signal switching device for a measurement system in order to solve the conventional drawbacks. The device is a plurality of relay circuits, and in each relay circuit, a plurality of relays that simultaneously switch a signal line for inputting an analog signal from a measuring instrument and a reference signal line, and an insulation signal conversion in which the relays are connected. And a relay drive circuit that controls the opening and closing timings of a plurality of relays, and an analog signal received from a plurality of relays via an insulation signal converter, and a measurement that controls the relay drive circuit while converting the analog signal to a digital signal. And a control unit.

A transformer can be used as the isolated signal converter.

Further, the relay drive circuit can sequentially switch the relays without simultaneously turning on two or more relays.

The measurement and control unit is provided with storage means and can store the converted digital signal.

[0009]

1 is a block diagram of an embodiment of a multi-channel signal switching device for a measuring system according to the present invention. The switching device is a two-circuit relay R1, R2,
... Rn, and these relays are respectively connected to ports for signal and common channels Ch1, Ch2, ... Chn. Those relays operate so as to switch the signal line and the common line at the same time to turn them on or off. The reference potential to be measured is input to the common channel. The number of channels can be changed according to the number of relay circuits, for example, 64 channels, 96 channels,
It can be 128 channels, 256 channels or 4096 channels.

Those two circuit relays R1, R2, ... R
n is connected to a single isolated signal converter 2. It is composed of a transformer, for example, and functions to separate the signal from each channel from the external signal processing device or the like on an electric circuit. The isolated signal converter 2 is a measurement and control unit 3
It is connected to the. The measurement and control unit 3 receives the analog signal from the insulation signal converter 2 and converts it into a digital signal. Then, the converted digital signal is stored as data or is output as a data signal to a device connected to the outside via the line 3a. The output data signal can be edited and displayed as needed by a signal processing device (not shown). Measurement and control unit 3
A relay drive circuit 4 for a channel selector is connected to. The relay circuit is a two-circuit relay R1, R2, ...
.. Connected to Rn and open / close (OFF / ON) those relays at a predetermined time. For example, a drive signal is output to open and close each relay at 0.01 second intervals, 1 second intervals, or 1 day intervals or 1 month intervals. However, do not turn on multiple relays at the same time.

If it is not necessary to electrically separate the measurement object and the measurement and control unit, the insulation signal converter may be bypassed.

Using the device according to this embodiment, for example,
An example of the case where the voltage of each cell of the fuel cell is regularly measured will be described. In that case, two-circuit relay R1, R
2, ... Rn signal and common channel Ch1, Ch2,
... The Chn ports are connected to the positive and negative electrodes of each cell, respectively. Since the common channels are independent of each other, the reference potential corresponding to each cell can be used even in the actual use state where the cells of the fuel cell are connected in cascade. For example, when measuring the individual voltages of six cells connected in series at intervals of 1 second, the signal and common channels Ch1, Ch2, ...
Connect the line connected to the 6 port.

During operation of this device, the relay drive circuit 4
However, by switching the two-circuit relays R1, R2, ... R6 in order,
Connect the signal and common channels Ch1, Ch2, ... Ch6 to the isolated signal converter 2 at intervals of 1 second. Switching of the relay is performed so that both the signal line and the common line are switched at the same time.

Specifically, first, the two-circuit relay R1 is turned on by the drive signal from the relay drive circuit 4, and the signal line Ch1 and the common line Ch1 are connected to the isolated signal converter 2. As a result, the voltage signal of the cell to which the channel is connected is sent to the measurement and control unit 3 via the insulation signal converter 2. The two-circuit relay R1 is switched off immediately. Next, when 1 second elapses after the two-circuit relay R1 is switched off, the relay drive circuit 4 becomes
Outputs a relay drive signal to switch circuit relay R2 to ON. As a result, the signal line Ch2 and the common line Ch2 are connected to the isolated signal converter 2. As a result, the voltage signal of the cell to which the channel is connected is sent to the measurement and control unit 3 via the insulation signal converter 2. The two-circuit relay R2 is immediately switched off. This operation is performed until the two-circuit relay R6 is turned on and off, and if necessary, the operation is repeated again from the relay R1.

The measurement and control section 3 converts an analog signal supplied each time the relay is driven into a digital signal. Those data are stored in the storage device therein. When a personal computer is connected to the line 3a of the measurement and control unit 3, necessary data is sent from the storage device to the personal computer, and the data is displayed in an appropriate form by the function of the application software of the personal computer. , Can be displayed as statistical data.

[0016]

According to the present invention, since a plurality of relays are controlled by the relay drive circuit and connected to one insulation signal converter in order, the device can be downsized and the cost can be greatly reduced. Can be made.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of a multi-channel signal switching device for a measurement system according to the present invention.

[Explanation of symbols]

R1, R2, ... Rn 2 circuit relay 2 Isolated signal converter 3 Measurement and control unit 3a line 4 Relay drive circuit

Claims (4)

[Claims] 1. A plurality of relay circuits, wherein in each relay circuit, a plurality of relays for simultaneously switching a signal line for inputting an analog signal from a measuring device and a reference signal line, and an insulation to which the relays are connected. A signal converter, a relay drive circuit that controls the opening and closing timings of the plurality of relays, and an analog signal received from the plurality of relays via the insulating signal converter into a digital signal, and the relay drive A multi-channel signal switching device for a measurement system, comprising a measurement and control unit for controlling a circuit. 2. The device of claim 1, wherein the isolated signal converter comprises a transformer, an analog photocoupler or a capacitor coupled coupler. 3. The device according to claim 1, wherein the relay drive circuit sequentially switches the relays without simultaneously turning on two or more relays. 4. The apparatus according to claim 1, wherein the measurement and control unit includes storage means for storing the converted digital signal.