JPH0766020B2 - Circuit check device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a circuit check device.

[Conventional technology]

In buildings, factories, etc., local equipment such as pumps and air conditioners and a central monitoring panel are connected by a control line to form one system, and the local monitoring panel controls the local equipment.

As shown in FIG. 4, there are six possible connection relationships between the central monitoring board and local equipment. In the same figure, the left side of the broken line 1 shows the circuit corresponding to the central monitoring board, and the right side shows the circuit corresponding to the local equipment. And S is a signal input contact,
Ry is a relay, VR is a variable resistor, R is a resistor, and V _CC is a power supply voltage. Further, (A) to (D) of the same figure show a digital system whose system is controlled by a digital signal, (E) and (F) show an analog system which is controlled by an analog signal, and arrows indicate The direction of signal flow in each system is shown.

Therefore, if these systems cannot perform the predetermined functions, is the location of the trouble on the central monitoring board side?
In many cases, it is not immediately obvious whether it is on the side of the local equipment or on the wayway.

[Problems to be solved by the invention]

As a method of specifying the occurrence location, it is conceivable to replace the central monitoring board, the local equipment, and the line with one by one and perform an operation check.

Now, as shown in FIG. 5, two pumps A and B, which are local devices, are provided for one central monitoring panel C and are connected to lines L _A and L _B , respectively.
In a system connected via the above, it is assumed that one pump A can be started and stopped as prescribed by a command from the central monitoring board C, and the other pump B cannot be performed as prescribed.

In this case, the pump A was disconnected at the connection point P _A , the pump B was connected to the connection point P _A instead, and the start and stop of the pump B could be performed according to a command from the central monitoring panel C as prescribed. Then, the central monitoring board C or the connection point from the central monitoring board C
It can be considered that trouble has occurred in the line L _B of up to P _B. If you cannot start / stop even if you connect pump B to connection point P _A , consider that there is a problem with line L _B from connection point P _B to pump _B or pump B. You can In addition, L _A is from the connection point P _A to the pump A
Shows the tracks up to.

As described above, when there are at least two on-site devices that can start and stop independently, the trouble occurrence point can be relatively easily identified, but such a case is extremely rare. Also, as shown in FIGS. 4 (E) and 4 (F),
When the control of the system is performed by an analog signal, it is often difficult to reliably grasp when the value of the analog signal is slightly deviated.

The present invention has been made with the above matters in mind, and an object of the present invention is to provide the system as described above,
An object of the present invention is to provide a circuit check device which can be used in a simulated manner for both the central monitoring panel and local equipment and which is easy to handle.

[Means for solving problems]

In order to achieve the above-mentioned object, the circuit check device according to the present invention has an analog / digital changeover switch connected to one of the test terminals, and a first input / output changeover switch connected to one terminal side of the switch. A current measuring circuit formed by connecting an ammeter and a variable constant current circuit in series is provided, and a second input / output changeover switch operated in association with the first input / output changeover switch is provided on the other terminal side. , A first signal confirmation circuit is connected to one terminal side of the switch via a first voltage / non-voltage changeover switch, a rectifying circuit is provided on the other terminal side, and an output side of the rectifying circuit is provided. A second voltage confirming circuit and a third signal confirming circuit provided in parallel with each other through a switching element, and a second voltage confirming circuit operated in association with the first voltage / non-voltage changing switch. Via the non-voltage changeover switch It is characterized in that to connect the source circuit.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

FIG. 1 is a circuit diagram showing a configuration example of a circuit checking device according to the present invention. In FIG. 1, 1A and 1B are test terminals connected to a test circuit. An analog / digital changeover switch 2 (hereinafter referred to as switch 2) is connected to one test terminal 1A, and the other test terminal 1B is grounded via a fuse 3.

On one terminal 2A side (analog side) of the switch 2, a current measuring circuit 6 including an ammeter 4 and a variable constant current circuit 5 connected in series is provided. That is, the one terminal 2A,
A rectifying circuit 7 composed of _four rectifying elements D ₁ , D ₂ , D ₃ , D _{4 such as} diodes is provided, and a connection point P of the rectifying elements D ₁ , D ₂ is provided.
A digital ammeter 4 as an ammeter is provided between ₁₂ and the connection point P ₃₄ of the rectifying elements D ₃ and D ₄ . The ammeter 4 is constructed so that it can read, for example, three or more significant digits. 8 is the first connected to the connection point P ₂₃ of the rectifying elements D ₂ and D ₃ .
Input / output changeover switch (hereinafter referred to as switch 8)
The other end is connected to the terminal 8A (output side) with the 18 V power supply E ₈₁
Connected variable constant current circuit 5 is connected, the other terminal 8B side (input side), the resistance value, for example, via a 1k _Omega resistor of about 9 is grounded.

Here, the 18V power supply E ₈₁ is composed of two 9V dry batteries 10 and 10 and a power switch 11 which are connected in series, as shown in FIG. 2 (A). This configuration is
The same applies to the V power supplies E _{82 to} E ₈₆ . Further, as shown in FIG. 3, the variable constant current circuit 5 includes a regulator IC 12 connected to an 18V power source E ₈₁ , capacitors 13 and 14, resistors 15 to 1
7, variable resistance 18-22, changeover switch 23 and terminals 24-26
It consists of and. The resistance 15 and the variable resistances 18 to 20 are, for example, 200Ω, 1500Ω, 500Ω, and 25Ω, respectively, and the resistance 16 and the variable resistance 21 are 1200Ω and 50, respectively.
Ω is also used as a resistor 17 and a variable resistor 22, respectively.
230Ω and 20Ω can be used.

Then, when the terminal 24 is selected by the changeover switch 23, an appropriate current in the range of 4 to 20 mA can be obtained. In this case, the fine adjustment around 4 mA is performed by operating the variable resistor 19, and the fine adjustment around 20 mA is performed by operating the variable resistor 20. When either the terminal 25 or 26 is selected by the changeover switch 23, a current of 4 mA or 20 mA, which is the end value of 4 to 20 mA, can be obtained.

Referring again to FIG. 1, 27 is the other terminal 2B of the switch 2.
A second input / output changeover switch (hereinafter referred to as switch 27) provided on the side (digital side) is configured to interlock with the switch 8. One terminal of this switch 27
A first signal confirmation circuit 29 is connected to the 27A side (output side) via a first voltage / non-voltage changeover switch 28 (hereinafter referred to as switch 28).

The first signal confirmation circuit 29 is a light emitting element 30 such as an LED.
And a push switch 31 having normally-open contacts 311 and 312 interlocking with each other, and a 12V power source E _21, and the light emitting element 30 has one terminal 28A of the switch 28 via a resistor 32.
Side (voltage side). The 12V power supply E ₂₁ is connected to the voltage side terminal 2 via the normally open contact 311 of the push switch 31.
Connected to 8A. One end of normally open contact 312 is switch 28
Is connected to the other terminal 28B side (non-voltage side) and the other end is grounded.

Here, the 12V power supply E ₂₁ is, as shown in FIG. 2B, an 18V power supply E ₈₂ , a regulator IC 33, and a capacitor 3
It is composed of 4,35 and. This configuration is
The same applies to the 12V power supply E ₂₂ .

36 is a rectifier circuit consisting of the other four rectifying elements D ₅ such as a diode which is provided to the terminal 27B side (input _{side), D 6, D 7,} D 8 of the switch 27, the rectifying element D _5, D ₈ A photocoupler 37 as a switching element is provided between the connection point P ₅₈ and the connection point P ₆₇ of the rectifying elements D ₆ and D ₇ . 37D and 37T are a photodiode and a phototransistor, respectively. or,
The connection point P ₇₈ of the rectifying elements D ₇ and D ₈ is the second linking with the switch 28.
Is connected to the voltage / non-voltage changeover switch 38 (hereinafter referred to as switch 38). One terminal of this switch 38
38A (voltage side) is grounded, and the other terminal 38B (non-voltage side) is connected to a 12V power supply E ₂₂ .

Reference numerals 39 and 40 denote a second signal confirmation circuit and a third signal confirmation circuit, which are provided in parallel with each other on the output side of the rectifier circuit 36 via the photocoupler 37.

The second signal confirmation circuit 39 includes an 18V power supply E ₈₃ , E ₈₄ , and an inverting element 4
1, a transistor 42, a light emitting element 43 such as an LED, etc., and the 18V power source E ₈₃ is connected to the collector of a phototransistor 37T via a resistor 44. The emitter of this phototransistor 37T is grounded. One end of the inverting element 41 is connected to the collector and the other end is connected to the resistor 45.
Is connected to the base of the transistor 42 through.
A light emitting element 43 is connected to the collector of the transistor 42 via a resistor 46.
Power supply E ₈₄ is connected. The emitter of the transistor 42 is grounded.

Further, the third signal confirmation circuit 40 includes a flip-flop (for example, RS type) 47, a transistor 48, and a light emitting element 4 such as an LED.
9, normally open push switch 50, 18V power supply E ₈₅ , E ₈₆ , capacitor 51, etc.
The S terminal of 47 is connected between the inverting element 41 and the resistor 45,
The Q terminal is connected to the base of the transistor 48 via the resistor 52. This transistor 48 has a resistor on the collector side.
A light emitting element 49 is connected via 53, and this light emitting element 49
18V power supply E ₈₅ is connected. The emitter of transistor 48 is grounded. Further, a push switch 50 is connected to the R terminal of the flip-flop 47, a capacitor 51 is connected in parallel to the push switch 50, and a 18 V
Power supply E ₈₆ is connected in series.

Next, the operation of the circuit checking device having the above configuration will be described.

(1) When the device of the present invention is used as the central monitoring panel of FIG. 4 (A) or the local equipment of FIG. 4 (C), switch 2 is switched to the digital terminal 2B side and switch 8
And switch 27 to the output terminal 8A, 27A side,
Further, the switches 28 and 38 are respectively provided with voltage terminals.
Switch to 28A, 38A side.

In this state, when the push switch 31 is turned on, + 12V (signal) is output between the test terminals 1A and 1B by closing the normally open contact 311 and the light emitting element 30 is turned on. You can see that

(2) When the device of the present invention is used as the on-site equipment of FIG. 4 (A) or the central monitoring board of FIG. 4 (C), switch 2 is switched to the digital terminal 2B side, and switch 8,
Switch the switches 27 to the input terminals 8B and 27B, respectively, and switch the switches 28 and 38 to the non-voltage terminals 28, respectively.
Switch to B, 38B side.

In this state, when a signal is input to the test terminals 1A and 1B, the output of the inverting element 41 is at the "H" level while the signal is being input, so that the transistor 24 is turned on and light is emitted. The element 43 lights up. At this time, the flip-flop 47 is also set at the same time, so that the transistor 48 is turned on and the light emitting element 49 is also turned on. When the signal disappears, the light emitting element 43 is turned off, but the light emitting element 49 continues to be turned on until the push switch 50 is turned on and the flip-flop 47 is reset.

(3) When the device of the present invention is used as the central monitoring panel of FIG. 4 (B) or the on-site equipment of FIG. 4 (D), switch 2 is switched to the digital terminal 2B side, and switch 8,
Switch the switches 27 to the output terminals 8A and 27A respectively, and further switch the switches 28 and 38 to the non-voltage terminals 28
Switch to B, 38B side.

When the push switch 31 is turned on in this state,
This is the same as when the test terminals 1A and 1B are short-circuited, a signal is output, and the light emitting element 30 is turned on. Therefore, it is possible to confirm that the signal is output.

(4) When the device of the present invention is used as the on-site equipment of FIG. 4 (B) or the central monitoring board of FIG. 4 (D), switch 2 is switched to the digital terminal 2B side, and switch 8,
Switch the switches 27 to the output terminals 8A and 27A respectively, and further switch the switches 28 and 38 to the non-voltage terminals 28
Switch to B, 38B side.

When the test terminals 1A and 1B are short-circuited, the light emitting element 43 is lit during that time. When the short circuit ends, the light emitting element 43 is turned off, but the light emitting element 49 continues to be turned on until the push switch 50 is turned on and the flip-flop 47 is reset.

(5) When the device of the present invention is used as the central monitoring panel of FIG. 4 (E) or the local equipment of FIG. 4 (F), switch 2 is switched to the analog terminal 2A side, and switch 8 and switch 27 are output respectively. Switch to terminals 8A and 27A.

In this state, 3 to 21mA by the variable constant current circuit 5.
A variable and stable current can be output between the test terminals 1A and 1B. Further, the current value at that time can be read with high accuracy by the digital ammeter 4.

(6) When the device of the present invention is used as the on-site equipment of FIG. 4 (E) or the central monitoring panel of FIG. 4 (F), switch 2 is switched to the analog terminal 2A side, and switch 8 and switch 27 are input respectively. Switch to terminals 8B and 27B.

The current value of the analog signal input through the test terminals 1A and 1B can be read with high accuracy by the digital ammeter 4.

As is clear from the above description of the operation, the circuit check device according to the present invention can be applied to the system of all aspects shown in FIG. By using one or more of this circuit check device in the adjustment of these systems, it is possible to accurately grasp the status of the central monitoring panel and local equipment, and therefore to accurately identify the trouble occurrence point in the system. can do.

Although the above-described embodiment was for a 12V circuit, the present invention is not limited to this, and by appropriately changing the battery voltage, the resistance value, etc., it is possible to obtain a 24V circuit or the like as appropriate. Needless to say. Also, in a system (not shown in Fig. 4) that transmits on / off of local equipment depending on the magnitude of current, the current value of the variable constant current circuit is set to 4 mA or 20 mA, and this circuit check device is It can be a pseudo-terminal device of the central monitoring board, and therefore the circuit checking device can adjust the system in various ways.

〔The invention's effect〕

As described above, in the circuit check device of the present invention, the analog / digital changeover switch is connected to one of the test terminals, and the ammeter is connected to the one terminal side of the switch via the first input / output changeover switch. A current measuring circuit formed by connecting a variable constant current circuit in series is provided, and a second input / output changeover switch operated in association with the first input / output changeover switch is provided on the other terminal side, and the switch is provided. The first signal confirmation circuit is connected to the one terminal side via the first voltage / non-voltage changeover switch, the rectification circuit is provided on the other terminal side, and the switching element is provided on the output side of the rectification circuit. A second signal confirmation circuit and a third signal confirmation circuit are provided in parallel with each other via a switch, and a second voltage / non-voltage changeover operated in association with the first voltage / non-voltage changeover switch Power supply circuit via switch Because it is constituted by continued and can also be simulated in any of the central monitor board and local devices of the system of various aspects. Therefore, it can be used not only to identify the trouble occurrence point in the system, but also to check the circuit etc. for either the central monitoring panel or the on-site equipment. When construction is carried out jointly by multiple contractors, the parts in charge can be checked independently of each other. Further, the circuit checking device of the present invention is particularly suitable for the above use because it is small and portable.

[Brief description of drawings]

1 to 3 show an embodiment of the present invention, FIG. 1 is a circuit diagram of a circuit check device, and FIGS. 2 (A) and 2 (B) are circuit diagrams showing a configuration example of a power supply. FIG. 4 is a circuit diagram showing a configuration example of a variable constant current circuit, FIG. 4 is a circuit diagram showing a connection relationship between a central monitoring panel and on-site equipment, and FIG. 5 is a circuit diagram for explaining a conventional technique. 1A, 1B …… test terminal, 2 …… analog / digital selector switch, 2A, 2B …… terminal, 4 …… ammeter, 5 …… variable constant current circuit, 6 …… current measurement circuit, 8 …… first I / O selector switch, 27 ... second I / O selector switch, 27A,
27B ... terminal, 28 ... first voltage / non-voltage changeover switch, 29 ... first signal confirmation circuit, 36 ... rectifier circuit, 37 ...
... Switching element, 38 ... second voltage / non-voltage changeover switch, 39 ... second signal confirmation circuit, 40 ... third signal confirmation circuit, E ₂₂ ... power supply circuit.

Claims (1)

[Claims] 1. An analog / digital changeover switch is connected to one of the test terminals, and an ammeter and a variable constant current circuit are connected in series to one terminal side of the switch via a first input / output changeover switch. And a second input / output changeover switch which is operated in association with the first input / output changeover switch, is provided on the other terminal side, and the first input / output changeover switch is provided on one terminal side of the switch. The first signal confirmation circuit is connected through the voltage / non-voltage changeover switch, the rectification circuit is provided on the other terminal side, and the second signal confirmation circuit is provided on the output side of the rectification circuit via the switching element. Also, the third signal confirmation circuit is provided in parallel with each other, and the power supply circuit is connected via the second voltage / non-voltage changeover switch operated in association with the first voltage / non-voltage changeover switch. Circuit check characterized by Location.