JP2742845B2 - Subscriber line test method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention is used for maintenance of telephones and other wired communication lines. The present invention is used for a subscriber line in which a station and a subscriber are connected by a pair of lines. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to test monitoring of a communication line using a subscriber protector that is inserted at a demarcation point between an outdoor wiring and a home wiring of a subscriber line and includes a lightning arrester for short-circuiting and grounding an abnormally high voltage generated in the line. . BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protector for a subscriber having a built-in relay contact capable of remotely separating outdoor wiring and home wiring by remote control, and a test and monitoring apparatus for the remote control.

[0002]

2. Description of the Related Art A subscriber can freely connect a device to a telephone or a terminal of a communication line or change a home wiring. A maintenance company manages outdoor wiring, and a home wiring is subscribed. The maintenance and management on the part of the user is now determined by the line usage contract. In this case, separation at the maintenance demarcation point is required. That is, when a failure occurs in a communication line, it is necessary to determine whether the failure location is an outdoor wiring or a home wiring. If a maintenance worker is dispatched to the outside wiring entry point for this separation, the number of man-hours increases. For this purpose, a circuit for separation is mounted inside the subscriber protector including the lightning arrester inserted at the demarcation point between the outdoor wiring and the house wiring, and the separation circuit is operated and remotely controlled from the station by the station. A subscriber protector that can be monitored is used, and a test monitoring device provided at the station side remotely controls the subscriber protector to perform test monitoring.

[0003] As an example of this, a subscriber security provided with a pair of central office terminals, a ground terminal, a lightning arrester connected between the pair of local office terminals and the ground terminal, and a pair of home extension terminals. The terminal has a built-in termination circuit that is connected between the central office terminals when it is connected between a pair of local office terminals, and a relay contact is provided, usually connecting the central office terminal and the home terminal to a closed circuit. The closed state is opened by a disconnection control signal sent from the station by remote control, and the office line terminal is connected to this termination circuit. In order to remotely control this relay contact, a test monitoring device installed in the station is used to send a cut-off control signal to this office line, and after performing a loop return test or the like in the cut-off state, the cut-off control signal is sent to the station. Line to return the relay contacts to their normal closed state. A control circuit that detects the disconnection control signal sent between the office line terminals to set the open state, detects the return control signal, and sets the closed state is installed in the subscriber protector. ing.

[0004]

On the other hand, in the line maintenance work of the subscriber line, it is necessary to connect the line on the office side and the line on the subscriber side correctly so as not to be interchanged with other subscribers. In order to confirm the connection, it is necessary to perform a work procedure such as transmitting a call signal to the subscriber's line to have the subscriber's terminal respond, and asking the responding person for the subscriber's number. In such a work procedure, for example, many pairs of subscriber lines are disconnected at once due to a disaster or a traffic accident,
When restoring this, it is necessary to check all the subscriber lines, and the man-hour for this work becomes extremely large. Also, the subscriber does not always receive a response due to absence or the like. Moreover, the subscriber is a customer for the telecommunications carrier, and it is not appropriate to trouble the customer each time for maintenance work.

The present invention focuses on mounting a device capable of identifying a line in addition to simply separating the line in the subscriber protector that can be remotely controlled as described above.

That is, a subscriber protector inserted at the demarcation point between the outdoor wiring and the home wiring can be separated at the maintenance demarcation point by remote control from the station side, and even if the subscriber does not receive a response, It is an object of the present invention to provide a device capable of confirming connection of a subscriber line. It is a further object of the present invention to provide a device that is in harmony with line segmentation using existing subscriber protectors.

[0007]

SUMMARY OF THE INVENTION According to the present invention, a storage circuit in which a unique identification code is set is mounted inside a subscriber protector which can be separated by remote control, and a test monitor installed at a station side is provided. The identification code set in the storage circuit is transmitted through the relay contact according to the remote control operation from the apparatus, and the identification code is received and displayed by the test monitoring apparatus.

[0008] The identification code sent to the line can be displayed on the optical line terminal so that the connection can be confirmed without receiving a response from the operation of the subscriber unit.

That is, according to the present invention, a pair of local line terminals (L
1, L2), a ground terminal (E), and a lightning arrester (AR) connected between the pair of local line terminals and the ground terminal.
A pair of home extension terminals (I1, I2), a terminal circuit (T) connected between the local line terminals when connected between the pair of local line terminals, and the local line terminal when the circuit is closed. A relay contact (r1, r2) is connected to each of the home extension terminals to disconnect the central office terminal from the home extension terminal at the time of opening and connect the terminating circuit between the pair of local extension terminals, and control the relay contact. A control circuit (CONT) for detecting the disconnection control signal between the pair of local line terminals to be in the open state and detecting the return control signal to be in the closed state, and storing a unique identification code. Circuit (MEM)
And an identification code transmission circuit (IDG) for transmitting the identification code set in the storage circuit between the pair of office terminals via the relay contact. Then, a test monitoring device is connected to the station side, the switching control signal and the switching back control signal are transmitted to the subscriber protector, and the identification code transmission circuit (ID
The identification code transmitted by G) is received and displayed. The control circuit responds to the arrival of the separation control signal.
Equipped with a first photocoupler light emitting element (PIS)
I have.

The identification code sending circuit (IDG) includes a means for generating an identification code set in the storage circuit (MEM) as a serial pulse, a second photocoupler (PH2) driven by the serial pulse, and a control circuit. First
Conducted by the light emission of the light emitting element of the photocoupler and its light emission disappeared
If there is a current exceeding the predetermined value,
A thyristor-type light-receiving element for maintaining, the light-receiving element of the second photocoupler is connected in a DC loop of a line that is folded back and connected by a subscriber protector, and a receiving circuit of the test monitoring device is provided. And a means for receiving an identification code from the fluctuation of the DC loop current of this line.

[0011] The identification code sending circuit (IDG) shall be the structure in which the power supply current is branched from the DC loop current of the folded connected line in protector for the subscriber.

[0012]

In the normal communication line utilization state, the relay contact (r
1, r2) are a local line terminal (L1, L2) and a home terminal (I
1, I2). This relay contact is remotely controlled by a test monitoring device installed on the station side. That is, when the test monitoring device installed at the station side cuts out the control signal to the station line and sends a control signal, the relay in the subscriber protector of the present invention is activated, and the relay contact disconnects the home terminal and the station line terminal (L1, L2). And the termination circuit (T). The direct current is maintained in its connection via the termination circuit (T). In this case, the separation control signal is the reversal of the DC polarity of the local line.

When this switching connection is made, a part of the current is shunted and supplied as a power supply current to the identification code sending circuit (IDG), and the identification code stored in the storage circuit (MEM) is transmitted to the central office terminal (ID). L1 and L2) are serially transmitted as a change in DC current. The test monitoring device provided at the station receives and displays this identification code. The identification code set on this subscriber protector does not necessarily correspond to the subscriber number, but can be translated into the subscriber number in another correspondence table. This identification code can be used as it is without taking the above correspondence.

After execution of the test, a switchback control signal is sent from the station-side test monitoring device, and the relay contacts (r1, r2)
Set to normal use. The switchback control signal here is to restore the DC polarity of the office line to the normal use state.

A test monitoring device (TS) provided on the station side for performing remote control and displaying an identification code is provided in the station where the exchange is installed, and is designed as a simple portable monitoring device (Q). It can also be used at track maintenance sites.

[0016]

FIG. 1 is a block diagram of a protector for a subscriber according to an embodiment of the present invention. This subscriber protector is installed in the same manner as a normal subscriber protector at a maintenance demarcation point where the office line is drawn into the subscriber's house, for example, under a house eaves. This device includes a pair of local line terminals L1, L2, a ground terminal E, and a pair of home extension terminals I1, I2. Terminals L1 and L2 are connected to the central office exchange via a subscriber line. The terminals I1 and I2 are connected to terminals installed in the house via in-house wiring.

The subscriber protector has a pair of central office terminals L.
1, a lightning arrester AR connected between L2 and a ground terminal. Further, this apparatus is provided with fuses F1 and F2 for connecting the office line terminals L1 and L2 and the home extension terminals I1 and I2. These are known circuits provided on the outdoor line so that abnormal high voltage generated by contact with a power line or the like or lightning strike does not flow into the in-home device.

Further, at the time of closing, the station line terminals L1, L
2 and the home extension terminals I1 and I2, respectively, and, when open, disconnect the local office terminals L1 and L2 from the home extension terminals I1 and I2 and terminate the terminal circuit T between the pair of local office terminals L1 and L2.
Are provided with relay contacts r1 and r2. Further, by controlling the relay contacts r1 and r2, a pair of local line terminals L1,
A disconnection control signal between L2 (in this example, the reversal of the DC polarity between the office line terminals) is detected, the state is opened, and a return control signal (in this example, the restoration of the DC polarity between the office line terminals) is detected. Control circuit CONT for bringing the circuit into the closed state
And

These configurations are conventionally known circuits which enable separation by remote control.
No. 4354). Here, a feature of the present invention is that a storage circuit MEM in which a unique identification code is set, and an identification code transmission circuit IDG connected to the termination circuit T and transmitting the identification code set in this storage circuit through the relay contact. And where it is. Further, the present invention is characterized in that a power supply current (indicated as POW in the figure) used in the identification code sending circuit IDG and the storage circuit MEM is branched from a DC holding current flowing through the termination circuit T (in FIG. Is denoted by D), the separation control circuit CONT includes a light emitting element P1S that conducts and emits light in a state of polarity inversion, and the branching circuit includes the light emitting element P1
A thyristor-type light receiving element P1R that receives the S output light and conducts is connected in series. This thyristor type
The optical element P1R was once turned on by receiving light.
After that, the conduction state is maintained as long as the current exceeding the specified value continues
Element.

A drive circuit for the light emitting element P1S is connected to a time constant circuit (a capacitor indicated by C1 in the figure) having a time constant longer than the chattering duration of the relay contacts r1 and r2.

The operation of the circuit thus constructed will be described. In a state where this line is normally used, that is, in a call state, a communication state, a call waiting state, etc., the relay contacts r1 and r2 are shown in FIG. In a state where
The office line terminals L1 and L2 are connected to the home extension terminals I1 and I2. At this time, the control circuit CONT is not operating. That is, considering the call waiting state, as an example, since a zero potential is applied to the local line terminal L2 and a DC voltage of +48 V is applied to the local line terminal L1, no DC current is generated in the control circuit CONT. In the call state or the communication state, since the home terminal device connected between the home extension terminals I1 and I2 connects the DC circuit, the voltage between the terminals decreases, but the local line terminal L is still connected.
1 is a positive potential with respect to the local line terminal L2, and in this case, no DC current is generated in the control circuit CONT.

In the state where the remote control is performed, the DC voltage polarities of the local line terminals L1 and L2 are inverted as a separation control signal. In this embodiment, not only the above-mentioned +48 V is changed to -48 V, but also a voltage having a somewhat large absolute value is applied. This is because in the polarity inversion state, a part of the holding current is shunted to be used as the power supply current by the identification code sending circuit, and the operation of the relay RL is ensured.

When the DC polarities of the local line terminals L1 and L2 are reversed, a DC current flows through the control circuit CONT and the relay RL operates. This relay RL allows the relay contacts r1 and r
2 is switched, the home extension terminals I1 and I2 are disconnected, and a terminating circuit T is connected between the local line terminals L1 and L2 via a fuse F2. The termination circuit T has a photocoupler P
Although the light receiving element of H2 is inserted, this light receiving element is set to be conductive in a non-light emitting state and non-conductive in a light emitting state. That is, when the photocoupler PH2 is not operating, the conduction state is established and the direct current is conducted to the terminal circuit T. Note that the relay RL is a latch relay.

In this state, from the branch point D in FIG.
The power supply current is branched and supplied to the OW, and the identification code sending circuit I
DG starts. The detailed description of the power supply circuit of the identification code transmission circuit IDG is omitted. The clock signal generation circuit CLK is activated by the power supply current, and the clock signal generation circuit CL is activated.
A clock signal is transmitted from K, and the identification code set in the storage circuit MEM appears at the terminal SIG as a serial pulse. This is supplied to the base of the transistor TR1 via the resistor R4, and opens and closes the transistor TR1 according to the serial pulse of the identification code. In response, the photocoupler PH2 operates and the identification code is transmitted to the local line terminals L1 and L2 as a DC current strength signal.

This serial pulse is monitored and displayed by the station side device. After receiving the serial pulse, the station-side device can execute a loop-back test and other tests with the relay contacts r1 and r2 connected to the termination circuit T.

When these tests are completed, a switchback control signal is transmitted from the optical line terminal.

In the circuit of this embodiment, the light emitting element P1S is connected in series to the relay RL, and the light generated by the light emitting element P1S is inserted in series to the power supply current branch point of the identification code sending circuit IDG. Moreover, the light receiving element P1R is of a thyristor type. That is, the conduction state is maintained even when the light emission of the light emitting element P1S is extinguished, and becomes non-conductive when the current of the light receiving element P1R disappears after the light emission is extinguished. Another reason is to surely cut off the power supply current by other line test and switchback control signals.

When a current flows through the relay RL due to the DC polarity reversal of the local line terminals L1 and L2, the relay RL starts operating. At this point, the light emitting element P1S emits light, and the light receiving element P1R is turned on. Relay contacts r1 and r2
Is switched, a current flows through the termination circuit T, so that the DC voltage between the local line terminals L1 and L2 decreases. Therefore, the light emission of the light emitting element P1S becomes weak. Even in this state, once the current starts to flow through the light receiving element P1R, the power supply current is not interrupted even if the light emission of the light emitting element weakens.

In this embodiment, a capacitor C1 is connected as a time constant circuit to the drive circuit of the light emitting element P1S. This avoids the effects of relay chattering. The relay RL is activated and the relay contacts r1 and r
Even if 2 is switched, chattering occurs in the relay contact for a short time. When chattering occurs, the light receiving element P
When the direct current flowing through 1R fluctuates in a complicated manner, the conduction state may be interrupted. Therefore, after the relay RL starts operating, the relay contacts r1 and r2
Until the time during which the chattering occurs, the light emitting state of the light emitting element P1S is continued by the capacitor C1. As a result, even when chattering has occurred, the light receiving element P1R can maintain the conductive state continuously.

These are all techniques obtained as a result of tests under various conditions performed for the present invention.

Next, the identification code sending circuit IDG which is a main part of the present invention will be described in more detail. FIG. 2 shows a circuit configuration diagram of a storage circuit MEM for storing a unique identification code and a clock signal generation circuit CLK for reading out the stored contents of the storage circuit MEM and making it a serial pulse. The storage circuit MEM is configured by a plurality of (five in this example) cascaded programmable shift registers. The programmable connection of each shift register indicated by the symbol x in FIG. 2 is set in advance according to a unique identification code assigned to the subscriber protector. The clock signal generation circuit CLK includes a crystal oscillation element XTAL. The oscillation frequency is divided by a flip-flop circuit and supplied as a clock signal to a clock signal terminal CK of each shift register. Further, a control signal to be supplied to each shift register is generated according to the clock signal.

The identification code has a 32-bit structure, and is 2 32
Assignments can be made on the fly. This identification code sending circuit I
The signal output SIG of the DG was designed such that a signal of 32 bits + command bit was repeatedly transmitted twice for 0.13 seconds. FIG. 3 shows this signal waveform diagram. FIG. 3 shows a current waveform passing through the local line terminal L1 or L2.

The above embodiment is merely a design example.
The storage circuit can be similarly designed using a ROM, a digital switch, or other storage circuits without using a programmable shift register. In addition, the bit configuration and transmission form can be freely designed according to the number of lines to be handled and the like. The clock signal generation circuit also has a characteristic that can be freely designed according to the purpose of use of a suitable line.

In the above example, the power supply current is divided from the DC current. However, a configuration in which a small power supply is built in or a configuration in which the power supply current is supplied from the home terminal device is also possible.

In the above example, the simple example of using the forward / reverse polarity of the DC polarity of the local line has been described for the cut-off control signal and the cut-back control signal. is there.

Next, a test performed using the apparatus of this embodiment will be described.

FIG. 4 is a diagram showing an example of the configuration of a test monitoring apparatus provided on the station side for remotely controlling the subscriber protector. This test monitoring apparatus is connected to a station line to which a subscriber protector of the present invention is connected, and a control signal generating circuit 20 for sending a control signal and a switchback control signal to the station line.
And a receiving circuit 2 for receiving and storing the identification code arriving at the office line
1 and a display circuit 22 for numerically displaying the accumulation result of the receiving circuit 21.

FIG. 5 is an overall configuration diagram for explaining how the apparatus of the present invention is installed between a telephone station and a subscriber terminal. The subscriber protector according to the present invention is denoted by the symbol P in FIG.
Installed as The station-side test monitoring device TS described in FIG. 4 is mounted on a test stand. The station-side test monitoring device described with reference to FIG. 4 is configured to be portable and used as the test monitoring device Q. The portable test monitor Q operates on its own battery power supply and can be used on utility poles or in manholes.

Next, the test monitoring operation of these devices will be described with reference to FIG. When it is desired to check the connection between the exchange and the terminal from the test stand, the subscriber number of the terminal is dialed and the terminal is connected (reference numeral 40). If the other party responds by transmitting a call signal, the connection can be confirmed. However, if a response from the terminal cannot be obtained due to some reason, the connection cannot be confirmed by this method.

In the case where the subscriber protector of the present invention is provided on the terminal side, when the control signal generation circuit 20 of the test monitoring apparatus of FIG. The subscriber protector P operates the relay contact as described above to disconnect the office line from the terminal, and at the same time, connects to the termination circuit T (reference numeral 41). At this time, the line is connected to the demarcation point (here, the subscriber protector), and immediately after the connection, the subscriber protector P sends the set unique identification code (reference numeral 42). The station-side test monitoring device receives this in the receiving circuit 21 and displays it on the display circuit 22. As a result, it is possible to confirm that the line on which the test bench is to execute the test is the intended subscriber line even if there is no response from the terminal.

After the subscriber line has been confirmed and a normal line test (reference numeral 43) has been performed, when a return control signal is sent from the control signal generation circuit 20, the relay contact is restored and the operation is completed. (Reference numeral 44).

[0042]

As described above, according to the present invention, a subscriber protector inserted at a demarcation point between an outdoor wiring and a home wiring can be separated at the maintenance demarcation point by remote control from an office. , Without having the subscriber respond,
The connection of the subscriber line can be confirmed. The present invention can be implemented by adding a small additional circuit to an existing remote control monitoring device.

In the present invention, since the identification code sending circuit is connected to the termination circuit of the subscriber protector after the separation relay contact operates, the identification code sending circuit is used during line communication and other normal states. The circuit is completely isolated and has no effect on communication. In addition, an identification code is transmitted immediately after the operation of the isolation contact by a test similar to the existing line isolation test at the maintenance demarcation point, and the transmission of the identification code is terminated.
In Since power to the identification code sending circuit is Ru is supplied, can be prevented mistake due misidentification harmony well line with the conventional system. Further, when the identification code is transmitted due to a change in the DC current, the present invention can be implemented without affecting normal communication and existing communication line tests.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a protector for a subscriber according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a storage circuit and a clock signal generation circuit of the protector for a subscriber according to the embodiment of the present invention.

FIG. 3 is a diagram showing an identification code waveform according to the embodiment of the present invention.

FIG. 4 is a diagram showing a configuration example of a test monitoring device installed on the station side according to the present invention.

FIG. 5 is an overall configuration diagram illustrating an embodiment of the present invention.

FIG. 6 is a sequence diagram illustrating a procedure of test connection and remote control according to the present invention.

[Explanation of symbols]

 TS Test monitoring device Q Portable test monitoring device P Subscriber protector L1, L2 Central office terminal I1, I2 Home extension terminal E Ground terminal AR Lightning arrestor element CONT Cutting and switching back control circuit F1, F2 Fuse RL Relay r1 , R2 relay contact T termination circuit IDG identification code transmission circuit MEM storage circuit CLK clock signal generation circuit D power supply current branch point P1S light emitting element P1R light receiving element PH2 photocoupler POW power supply circuit for identification code transmission circuit

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Shigeru Fukushima 3-12-15 Chuo, Warabi City, Saitama Prefecture Nikko Electric Works Co., Ltd. (72) Inventor Mitsuo Hattori 1-1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation (72) Inventor Masao Oba 1-6-1, Uchisaiwai-cho, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation (56) References Patent 2626911 (JP, B2) JP 6-36523 (JP) , B2)

Claims (1)

(57) [Claims] 1. A relay contact for connecting a central office terminal and a home extension terminal when the circuit is closed, and disconnecting the central office terminal from the home extension terminal when the circuit is open and connecting a terminating circuit (T) between the pair of the local office terminals. (R1, r2), a control circuit (CONT) for controlling the relay contact, detecting a control signal for separating the pair of local line terminals, setting the open state, detecting a return control signal, and setting the closed state. An office line terminal of a subscriber protector having the following is connected to a subscriber line, and sends out the above-described cut-off control signal and the above-mentioned switch-back control signal to the station side of the subscriber line, and performs a test of this subscriber line. In a subscriber line test system to which a test monitoring device to be performed is connected, a storage circuit (MEM) in which a unique identification code is set in advance in the subscriber protector, and an identification set in the storage circuit An identification code sending circuit (IDG) for sending a signal between the pair of office line terminals via the relay contact, and a receiving circuit for receiving the identification code sent from the identification code sending circuit to the test monitoring device. And a display circuit for displaying a reception result of the reception circuit, wherein the control circuit is activated by the arrival of the separation control signal.
A light emitting element (PIS) of a first photocoupler that emits light, and the identification code sending circuit (IDG) includes the memory circuit (M
Means for generating the identification code set in (EM) as a serial pulse, and driven by the serial pulse
A second photocoupler (PH2) and the first photocoupler
Conduction due to light emission of the light emitting element
When there is a current exceeding the
The first photoreceptor (PIR) of the irista type first photocoupler
Wherein the light receiving element of the second photo coupler are connected to the DC loop of the folded connected line in protector for the subscriber, the receiving circuit of the test monitoring device from fluctuation of the DC loop current of the line The apparatus further includes means for receiving the identification code, wherein the identification code transmission circuit (IDG) is configured such that its power supply current is branched off from a DC loop current of a line that is looped back and connected by the subscriber protector. Subscriber line test method.