JP2790195B2 - Test transmitter for gas pressure remote monitoring system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a gas pressure remote monitoring system used for gas maintenance of a communication cable, when a monitoring device is newly installed or after the installation. The present invention relates to a test transmitter for checking whether or not a supply voltage, a calling signal transmission, and the like of a monitoring device are proper and operate properly during maintenance and inspection of the device.

[Conventional technology]

In a gas pressure remote monitoring system as part of maintenance of a gas-filled communication cable, a pressure transmitter, a flow transmitter, an alarm transmitter, and the like are used.

The pressure transmitter measures the pressure of the charged gas in the gas-filled communication cable, and sends an output current signal corresponding to the gas pressure value to a monitoring device provided in a telephone office or the like,
The flow transmitter measures the flow rate of the pressure sealed in the gas-filled communication cable, and sends an output current signal corresponding to the gas flow rate value to the monitoring device. And a plurality of receiving terminals for transmitting output current signals corresponding to these various contacts, and when one or more of the alarm contacts in the group of alarm contacts are activated, the corresponding contact is activated. The output current signal is set in advance so as to be sent to the monitoring device, and the monitoring device can determine which alarm contact has been activated based on the output current signal.

That is, as shown in FIG. 1, the gas pressure remote monitoring system includes a monitoring device 1 installed in a telephone office and the like, a pressure transmitter, a flow transmitter, an alarm transmitter, and the like, or a single unit. A plurality of transmitters 11 installed at remote locations are connected via power supply lines 7 and 7 'and signal lines 8 and 8' via a U-link 10 or a main switchboard 9 which is a broken piece 10 ', The monitoring device 1 includes a power supply 2 for supplying power to each transmitter 11 and signal lines 8 and 8 ′ from a transformer 4.
An address call signal generating unit 3 for sending a call signal S1 set for each transmitter 11 through a resistor, a resistor 5 for converting an output current signal sent from each transmitter 11 into a voltage signal, A voltmeter 6 for displaying a voltage drop value at the resistor 5 is provided.

Each of the transmitters 11 identifies the called address based on the frequency of the calling signal S1 from the address calling signal generator 3, and the called transmitter 11 is activated by the input of the calling signal S1 to generate a pressure signal. The device converts the gas pressure value, the flow transmitter converts the flow value of the gas body, and the alarm transmitter converts the operating state of the alarm contact into an output current value corresponding thereto, and outputs the output current signal to the monitoring device 1 as an output current signal. The data is sent out along the dotted line in FIG.

[Problems to be solved by the invention]

As described above, in the gas pressure remote monitoring system, each of the plurality of transmitters 11 is installed at each monitoring location while being connected to the monitoring line (hereinafter simply referred to as a line) of the gas-filled cable. , The gas supply state is measured, and the measurement result is sent to the monitoring apparatus 1 as an output current signal. After the monitoring apparatus 1 and the respective transmitters 11 are newly installed and connected to the line or already installed, There are the following problems when the maintenance and inspection of the monitoring device 1 is performed.

Monitors the output current signal from the called transmitter 11
When reading in the data, a data abnormality occurs due to a defect in the reading timing of the monitoring device 1 itself.

An abnormal phenomenon occurs due to erroneous connection between the monitoring device 1 and the line and breakage of the connection point.

Due to the poor balance of the signal line, it is affected by the state of pulse transmission etc. on other lines, and each transmitter
Abnormal phenomenon occurs in the operation of 11 and output current signal.

An abnormal phenomenon is caused by poor insulation of the line.

Conventionally, based on the assumption that these problems do not occur, the supply voltage from the monitoring device 1, the confirmation of the ringing signal, etc. are not performed,
Of course, there is no tester for confirming these, and usually, it is determined whether or not the gas pressure remote monitoring system is normal based on the output current signal of each transmitter 11 called by the calling signal S1 for each address.

For this reason, every time any abnormal phenomenon is caught by the monitoring device 1, it is determined that an abnormal phenomenon has occurred in the transmitter 11. Divided into the transmitter 11 connection side and the monitoring device 1 side,
A simple transmitter operation tester is connected to the line on the connection side of 11 to check the operation of each transmitter 11 and the like.
In the line on the side, the work of checking and confirming the supply voltage from the monitoring device 1, the frequency and the potential level of the address calling signal, and the observation of the waveform was performed.

As described above, in order to investigate the cause of the occurrence of the abnormal phenomenon, it is necessary to first determine whether the cause is on the transmitter 11 connection side or on the monitoring device 1 side by isolating the line. The confirmation work requires a large number of skilled persons with specialized knowledge and a long time, so that an enormous cost is required.

Further, as described above, since there was no tester for checking the supply voltage of the monitoring device 1, the calling signal S1, etc., each time the exploration investigation and the confirmation work were carried out, the inspection measuring instrument (AC / DC voltmeter, insulation measuring instrument) , Waveform observer, simple calling device, etc.) and tools must be prepared, and the work preparation is very large. In remote locations, a large amount of There was a problem that it took time.

Therefore, the present invention has been devised to solve the above-mentioned problems in the prior art, and the line is divided into the monitoring device side and the transmitter connection side by the switchboard, so that the monitoring device side can be easily and accurately. It is intended to be investigated.

[Means for solving the problem]

Means of the present invention for achieving the above object include: an input circuit section for inputting a call signal transmitted from a monitoring device installed in a telephone office or the like while maintaining the signal line balance; Comparing the frequency with a preset internal reference frequency, and having a frequency comparison unit that outputs a first drive signal when the frequency of the calling signal is within the range of the reference frequency; When the signal and the potential level are higher than a preset threshold value, a level monitor that outputs a second drive signal is provided. When a call signal is input, a preset reference output current is output. Signal
Having a reference output current generation circuit for sending out to the monitoring device; when the first drive signal and the second drive signal are simultaneously inputted, power is supplied to the reference output current generation circuit to generate the reference output current. A switch circuit section for activating the circuit; a reference output current generating circuit in which a current signal amount corresponding to a preset reference output current is written as data, and a code for outputting this data as a digital signal A D / A converter for converting a digital signal from the code converter into an analog voltage signal, and converting the analog voltage signal from the D / A converter into a current having a value proportional to the analog voltage signal value. And a voltage-current conversion unit for converting the current signal into a signal and sending the current signal as a reference output current signal to the monitoring device.

Some monitoring devices have a self-checking function, and some do not. Therefore, in order to support both monitoring devices, it is desirable to provide a switch for switching the frequency to be compared in the frequency comparison unit. .

Also, in order to check whether or not the drive power supply voltage supplied from the monitoring device to the test transmitter is higher than a certain level, the power supply voltage from the monitoring device is applied to the power supply input part from the monitoring device. It is preferable to provide a power supply voltage inspection unit for detecting whether or not the above is true.

[Action]

By connecting the test transmitter according to the present invention to the switchboard, the power supply voltage is supplied from the monitoring device,
The call signal is input to the level monitor and the frequency comparator through the signal input circuit.

In the level monitoring unit, the potential level of the input calling signal is compared with the potential level of a threshold value set in advance, and the second level is set only when the potential level of the calling signal is higher than the threshold value. A driving signal is output, and the frequency comparing unit determines whether or not the frequency of the input calling signal is within a frequency range set in advance, and when the frequency is within the range, the first driving is performed. Output a signal.

When the first drive signal from the frequency comparison unit and the second drive signal from the level monitoring unit are simultaneously input to the switch circuit unit, the switch circuit unit is activated, and the supply voltage from the monitoring device is reduced. Energize the reference output current generation circuit,
The reference output current generating circuit is driven.

In the code conversion section of the reference output current generation circuit, a digital signal as a data output which is a code combination for setting transmission of an arbitrary reference output current signal is formed in advance, and this digital signal is sent to the D / A conversion section. Output this D
It is converted to an analog voltage signal by the / A converter. The analog voltage signal from the D / A converter is input to the voltage / current converter, and is converted into a reference current signal proportional to the voltage value by the voltage / current converter. The reference current signal is used as a reference output current signal as a monitoring device. To send to.

As described above, the reference output current signal is transmitted in accordance with the code combination arbitrarily set, and the reference output current signal is read by the monitoring device, and whether or not the value of the read data and the value of the code combination exactly match. By confirming the above, an investigation by the monitoring device side of the line separated by the switchboard is achieved.

By the way, the monitoring device has an address calling signal generator separately assigned to each of the transmitters of channels 1 to n. The monitoring device calls the built-in pseudo transmitter in the n channel of the determined block. , The output current signal output from this transmitter is read as data, and the supply voltage, the calling signal, etc. are self-confirmed whether they are normal, and the output current from each transmitter without self-confirmation. There are some which use only signals as data.

When a monitoring device having the capability of self-checking is connected to the monitoring device side, the output current signal of the built-in pseudo transmitter is used as data only for the n-channel of the corresponding block, so that it may be overlapped data. In order to avoid the above problem, the threshold value of the frequency is switched and set by the changeover switch so that the test transmitter of the present invention does not operate with respect to the paging signal of the n channel. On the other hand, if a monitoring device that does not have the capability of confirming itself is connected to the monitoring device,
In the test transmitter of the present invention, the setting of the frequency threshold is changed by the changeover switch so as to operate for all calling signals from the monitoring device. It does not respond to signals outside the 1- (n-1) channel range and signal inputs such as external leads.

The level monitoring unit checks whether the signal level of the paging signal input from the monitoring device is equal to or higher than a predetermined threshold value, thereby inspecting the monitoring device side line for erroneous connection, insulation failure, and the like. .

The signal input circuit keeps the balance of the line on the monitoring device side, preventing abnormal operation from occurring in the operation of the test transmitter and the output current signal due to electromagnetic influences from other lines. I have.

By providing the power supply voltage inspection unit, it is possible to check the power supply function itself of the monitoring device, and thereby it is possible to know the failure of the monitoring device or the monitoring device side line.

〔Example〕

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

In FIG. 1, a power supply line 7 from the monitoring device 1
7 'and signal lines 8 and 8'
Each of the transmitters 11 is connected via a link 10 or a disconnection piece 10 '. In normal gas pressure remote monitoring, one of the U-link 10 and the disconnection piece 10 'of the switchboard 9 is always used, and the test transmitter 12 can be electrically connected to any of them. Therefore, when conducting a confirmation test, the monitoring device 1 and the transmitter 11 are connected to each other at the switchboard 9 and the test transmitter 12 is connected to the line on the monitoring device 1. Power supply voltage and call signal from monitoring device 1
Perform S1 confirmation test.

A stabilizing power supply unit 15 is provided at a connection end of the test transmitter 12 with the power supply lines 7 and 7 ′.
The input power to the inside is set to a constant value. On the input terminal side of the stabilized power supply unit 15, there is provided a power supply voltage inspection unit 13 for checking the power supply from the monitoring device 1 and for checking whether the power supply is equal to or more than a set fixed value. Yes,
The power supply voltage inspection unit 13 is configured by inserting and connecting a fixed resistor 14 ′ and an indicator lamp 14 in series between a positive pole and a negative pole. Is confirmed. Also, the signal lines 8, 8 '
A signal input circuit section 21 is provided at the connection end with
The balance of the signal lines 8, 8 'is properly maintained.

The call signal S1 input to the frequency comparison unit 17 is any one of 23 frequencies divided every 30 Hz, with one channel being 382.5 Hz and n channels (for example, 23 channels) being 1042.5 Hz. . If the calling signal S1 is equal to or higher than the frequency of the first channel, the comparison portion Fs outputs a signal of positive logic H if the frequency is lower than the frequency of the first channel, and the comparison portion Fs outputs a signal of the positive logic L if lower than the frequency of the channel. A comparison part Fx that outputs a signal of positive logic L if higher than the frequency of positive logic H and (n-1) channels, and a positive logic H if it is lower than the frequency of n channels and positive if higher than the frequency of n channels. A comparison section Fn for outputting a signal of logic L is provided, and the paging signal S1 is always input in parallel and compared with the frequency of the paging signal S1. A reference frequency generator 18 for setting and generating a reference frequency as a threshold to be compared with the input calling signal S1 is connected to these comparison parts Fs, Fx and Fn. Are reference frequencies F1, F2, and F3 for constantly comparing the frequency of the input calling signal S1 with the frequency comparing unit 17.
Are oscillated independently and transmitted to the frequency comparison unit 17. That is, it is the comparison part Fs that compares the frequency of the input call signal S1 with the reference frequency F1, the reference frequency F2 is compared in the comparison part Fx, and the reference frequency F3 is compared in the comparison part Fn. Therefore, when the output signals resulting from the comparisons at the comparison portions Fs, Fx, and Fn are respectively ANDed as input signals, they become positive logic H or positive logic L, and are output from the frequency comparison section 17 to the switch circuit section 20 from the frequency comparison section 17. One drive signal S2 is transmitted or not transmitted. The frequency comparing unit 17 is provided with a changeover switch 19 having a contact 19a and a contact 19b, and switches the test transmitter 12 depending on whether the monitoring device 1 has the self-checking capability or not. It works. That is, the contact 19a is a contact for the monitoring device 1 having a self-check function, and the changeover switch 19
Is set to the contact 19a, the comparison part Fx of the frequency comparison part 17 is set.
Is short-circuited to the output side and the input side for ANDing, and the output signal of the comparison portion Fx is used. This comparison part Fx
Is a positive logic H at the frequency of the call signal S1 up to the 1- (n-1) channel, and is a positive logic L at the frequency of the n-channel. The vessel 12 is brought into an operating state. Even when the n-channel calling signal S1 is input, the frequency comparison unit 17 does not send the first drive signal S2 to the switch circuit unit 20 and the switch circuit unit 20 remains in the normally open state. The transmitter 12 is in a non-operating state to prevent overlapping data. On the other hand, the contact 19b is a contact for the monitoring device 1 having no self-confirmation function, and when the changeover switch 19 is set to the contact 19b, the output side of the comparison part Fx of the frequency comparison unit 17 and the input side for ANDing are provided. Is in a cut-off state, and without using the output signal of the comparison part Fx, the signal of the positive logic H is always input to the input side for ANDing, and the other comparison parts Fs,
The first drive signal S2 is sent from the frequency comparing unit 17 to the switch circuit unit 20 from the 1st to (n-1) channels with both Fn being in the positive logic H state.

The setting switch 23 is connected to the code conversion unit 25 via a surge protection unit 24 that absorbs an intruding surge voltage and protects an internal circuit. The setting switch 23 is for setting the transmission of an arbitrary reference output current signal S4. According to the setting of the setting switch 23, a data output signal which is a code combination is formed. The signal is converted into a digital signal by the unit 25 and output. The analog voltage signal from the D / A conversion unit 26 is
The signal is input to the voltage-current converter 28 via.

The code conversion unit input 5 is a storage element, and is encoded by a binary-coded decimal code, a binary-coded hexadecimal code, or the like. For example, 0000 is 0, 0001 is 1, 0010 is 2, 0011 is 3 ...
1101 is set to 13, 1110 is set to 14, and 1111 is set to 15.

The threshold value in the frequency comparison unit 17 is determined by the reference frequency generated by the reference frequency generation unit 18,
When the frequency of S1 is Fo, a frequency lower than the frequency of one channel (a noise source generated for some reason) is _FL ,
The frequency of one channel is changed from F _S0 and two channels to (n
-2) The frequency up to the channel is F _X0 , the frequency of the (n-1) channel is F _X1 , the frequency of the n channel is F _N0 , n
If a frequency higher than the channel and F _H, the frequency comparison unit
17, as described above, there are comparison parts Fs, Fx, Fn,
When the call signal S1 is input, the frequency is compared with the frequency from the reference frequency generation unit 18 by each of the comparison parts Fs, Fx, and Fn which are always input in parallel, and are set to the positive logic H or the positive logic L.

The reference frequency generation unit 18 has reference frequency F1, F2, and F3, each of which has an independent generation unit.The frequency comparison unit 17 compares the frequency F1 with Fo by comparing the frequency F2 with the frequency F2. The comparison is performed by the comparison part Fx, and the comparison between the frequencies F3 and Fo is performed by the comparison part Fn.In this frequency comparison part 17, the comparison parts Fs and F are compared with the frequency Fo of the calling signal S1.
The output signals of x and Fn become positive logic H or positive logic L. The positive logic and the first drive signal S2 at the threshold of each comparison part Fs, Fx, Fn of the frequency comparison unit 17 are shown in FIG. It looks like the chart shown.

As described above, by giving the threshold value based on the frequency, it is possible to automatically confirm whether or not the calling signal S1 from the monitoring device 1 is normal.

〔The invention's effect〕

The present invention has the above-described configuration, and has the following effects.

When the monitoring device is newly installed or when the monitoring device is inspected after the installation, it is possible to easily and surely check whether or not the call signal is transmitted from the monitoring device.

When an abnormal phenomenon occurs, the line is divided into the monitoring device side and the transmitter connection side, and it is easy to check whether the cause of the abnormal phenomenon is on the monitoring device side or the transmitter connection side, and to perform a test. Therefore, it is extremely easy to investigate and examine the cause of the abnormal phenomenon.

Since the investigation and investigation of the cause of the abnormal phenomenon can be performed only with a portable transmitter for testing, the minimum necessary amount of portable equipment for investigating the cause of the abnormal phenomenon can be extremely reduced, and as a result, The transportation of necessary equipment when investigating the cause of the abnormal phenomenon becomes extremely easy, and the cause investigation work can be accomplished efficiently.

Confirmation of the supply voltage of the monitoring device and the quality of the ringing signal by the test transmitter is automatically achieved by the test transmitter, and thus does not require skilled skills, thereby sufficiently improving the work efficiency. It is possible to reduce labor costs and the like related to the cause investigation work.

In the case where the power supply voltage inspection unit is provided, not only the call signal from the monitoring device but also the supply voltage can be inspected, so that a comprehensive function and state inspection of the monitoring device can be performed.

When the changeover switch is provided, the test can be performed on all the monitoring devices regardless of the difference in the functions of the monitoring devices.

[Brief description of the drawings]

FIG. 1 is an electric circuit diagram showing an outline of a gas pressure remote monitoring system including a monitoring device, a power supply line and a signal line having the switchboard, and each transmitter. FIG. 2 is a block diagram showing an embodiment of the test transmitter according to the present invention. FIG. 3 is a table showing the positive logic of each comparison portion with respect to the frequency of the input signal and the positive logic of the first drive signal. DESCRIPTION OF SYMBOLS 1; monitoring device; 2; power supply for power supply; 3; call signal generator for address; 4; transformer; 5; resistor; 6; voltmeter, 7, 7 '; power supply line, 8, 8'; Signal line, 9; main switchboard, 10; U link, 10 '; disconnection piece, 11; transmitter, 12; test transmitter, 13;
Power supply voltage inspection unit, 14; indicator light, 14; fixed resistance, 15; stabilized power supply unit, 16; level monitoring unit, 17; frequency comparison unit, 18; reference frequency generation unit, 19; changeover switch, 19a, 19b; Contacts, 2
0; switch circuit section, 21; signal input circuit section, 22; reference output current generation circuit, 23; setting switch, 24; surge protection section, 2
5; code converter, 26; D / A converter, 27; amplifier, 28; voltage-current converter, S1; calling signal, S2; first drive signal, S3; second drive signal, S4; reference Output current signal.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Yoshiaki Mechin 7-31, Omorinishi, Ota-ku, Tokyo Sumiden Opcom Corporation (56) References JP-A-61-136333 (JP, A)

Claims (3)

(57) [Claims] 1. An input circuit section (21) for inputting a call signal (S1) sent from a monitoring device (1) installed in a telephone office or the like while maintaining a signal line balance, and the call signal (S1). A frequency comparison unit (17) that compares the frequency of S1) with an internal reference frequency and outputs a first drive signal (S2) when the frequency of the calling signal (S1) is within the range of the reference frequency; A level monitor (16) for outputting a second drive signal (S3) when the calling signal (S1) and the potential level are higher than a preset threshold value; As a result, a reference output current generating circuit (22) for sending a preset reference output current signal (S4) to the monitoring device (1), the first drive signal (S2) and the second drive The signal (S3) and the signal (S3) are input simultaneously, so that the reference output current generation circuit (22) And a switch circuit unit (20) that is turned on by supplying power to the reference output current generation circuit (22). A current signal amount corresponding to a preset reference output current is written as data in the reference output current generation circuit (22). A code converter (25) for outputting the data as a digital signal; and a code converter (2).
5) a D / A converter (26) for converting the digital signal from the D / A converter into an analog voltage signal, and a current signal having a value proportional to the analog voltage signal value from the analog voltage signal from the D / A converter (26) And a voltage-current converter (2) that sends the current signal as a reference output current signal (S4) to the monitoring device (1).
8) A test transmitter for a gas pressure remote monitoring system having a configuration including: 2. A test transmitter for a gas pressure remote monitoring system according to claim 1, wherein the frequency comparison section (17) is provided with a changeover switch (19) for switching a frequency to be compared. 3. A power supply voltage inspection section (13) for detecting whether or not a power supply voltage from the monitoring device (1) is equal to or higher than a predetermined value is provided at a power supply input portion from the monitoring device (1). Item 1
Or a test transmitter for the gas pressure remote monitoring system according to 2.