KR0131995B1 - Auto line fault detection device in the full electronic - Google Patents

Abstract

The present invention relates to an automatic line monitoring device for an electronic switchboard that automatically detects a line fault condition due to a ground or cross condition of a line and notifies an operator whether a hook-off of a predetermined channel is caused by a fault line condition. To this end, the present invention provides an electronic switching system for constructing a telephone circuit using a tip line and a ring line in an exchange period with each subscriber; Voltage difference detecting means for detecting a difference between the voltage of the first predetermined section on the tip line and the voltage of the second predetermined section on the ring line corresponding to the first predetermined section for each subscriber; Discriminating means for comparing the voltage difference detected by the voltage difference detecting means with a predetermined bias voltage to determine whether there is an abnormal state of a corresponding line for each subscriber, and outputting a discrimination result signal to the exchange side; A subscriber line interface circuit for outputting a hook-off status signal to the exchange side that detects whether the corresponding subscriber channel is normally hooked off by using the amount of current flowing on the tip line and the current flowing on the ring line for each subscriber. It is composed.

Description

Automatic line monitoring device of electronic exchange

1 is a block diagram of an automatic track monitoring apparatus according to the present invention.

2 is a detailed view of the line fault detection circuit shown in FIG.

* Explanation of symbols for main parts of the drawings

100, 110, 120: track monitoring unit 130: buffering means

191,111,121: Subscriber Line Interface Circuit (SLIC)

102,112,122: Line fault detection circuit (LFDC)

23: comparator 140: SHD data read control unit

150: LFD data read control unit 21: differential amplifier

22: low pass filter

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for monitoring a line of a subscriber circuit in a full electronic switching system, and particularly for automatically monitoring a hook-off due to an abnormal state on a line and informing a switch operator. It relates to an automatic line monitoring device.

To date, testing of the circuits of subscriber circuits has been carried out using an out test relay operated by the line tester. As a result, it was not possible to monitor the abnormality of the track in real time, and after receiving the failure report of the subscriber, the abnormality of the track was checked, so it took a long time for the repair to be completed. there was.

That is, the ground or cross state that may occur on the track of the subscriber circuit may occur from time to time according to the track, and in particular, the ground or cross state on the track frequently occurs due to poor insulation of the track in rainy weather, making the real-time test more difficult. In addition, when the system is installed, the interfacing or cross with other lines frequently occurs.In this case, the system checks whether the dial tone generated by the hook-off is caused by a normal arc or an abnormal track. Can't. However, when it is detected that the hook is off due to a line error, unnecessary load is generated on the system.

Accordingly, the present invention has been made to solve the above-mentioned problems, and automatically detects a track abnormality caused by a ground or cross condition of a track and notifies the operator whether a hook-off of a predetermined channel is caused by a track abnormality. It is an object of the present invention to provide an automatic line sensing device for an electronic exchange.

In order to achieve the above object, the automatic track monitoring device according to the present invention is a tip switch for each subscriber in an all-electronic switch that forms a telephone circuit using a tip line and a ring line during an exchange period with each subscriber. Voltage difference detecting means for detecting a difference between the voltage of the first predetermined section on the line and the voltage of the second predetermined section on the ring line; Discriminating means for comparing the voltage difference detected by the voltage difference detecting means with a predetermined bias voltage to determine whether there is an abnormal state of a corresponding line for each subscriber, and outputting a discrimination result signal to the exchange side; Subscriber line interface circuit for outputting the hook-off status signal to the exchange after detecting whether the corresponding subscriber channel is normally hooked off by using the amount of current flowing on the tip line and the current flowing on the ring line for each subscriber. Characterized in that.

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

FIG. 1 is a block diagram of an automatic line monitoring apparatus according to the present invention, which is applied to an electronic switch that forms a call line between a channel and a channel of each subscriber using a tip line and a ring line.

The automatic line monitoring device shown in FIG. 1 detects a hook-off state by the amount of current on the tip line and the ring line connected to each subscriber channel (CH 1 to CH N). (Switch Hook Detection Subscriber line interface circuit (hereinafter abbreviated as SHD) (hereinafter abbreviated as SLIC (Subscriber Line Interface Circuit) (101, 111, 121)), line fault detection by detecting a line fault condition (hereinafter abbreviated as LFD (Line Fault Detection)) SHD and LFD output from the line monitoring unit (100, 110, 120) and the line monitoring unit (100, 110, 120) consisting of a line fault detection circuit (hereinafter abbreviated as LFDC) (102, 112, 122) for outputting a signal in units of 8 channels, respectively Buffering means 130 for buffering and transmitting the same to the switch (not shown) through the same data bus, and the mode select signal and address signals (Address 0 to 1) applied from the switch (not shown). n) To a mode selection signal and an address signal applied from the SHD data read control unit 140 and an exchanger (not shown) to output a control signal for reading the SHD data stored in the buffering means 130 in units of eight channels. By the LFD data read control unit 150 for outputting a control signal for reading the LFD signal stored in the buffering means 130 in units of eight channels.

The automatic track monitoring device configured as described above is driven as follows.

First, using the difference between the current on the tip line and the current on the ring line is such that in normal cases, the current flowing through the tip wire becomes a source and the current flowing through the ring wire becomes a sink. Since the current applied through the tip line is output through the ring line, the current flowing through the tip line and the current flowing through the ring line become the same value, and the difference between the current flowing through the ring line and the tip line becomes '0'.

Therefore, when there is an abnormality in the line, the difference in current between the tip line and the ring line described above is not zero as described above, and the current difference is generated. At this time, the current difference value for determining the abnormal state does not necessarily include all the values except for 0 as described above, and is set in consideration of a certain tolerance. As described above, the current difference value for determining the abnormal state may be a source of the ring wire, a source of the ring wire, a sink of the tip wire, or both of the tip wire and the ring wire as a source, in addition to the case where the tip wire is used as the source and the ring is synchronized. Each case is set differently. However, the present embodiment will be described with reference to a case where the current of the tip wire is used as the source and the current of the ring wire is synchronized.

As described above, in order to detect an abnormal state of the line, the current applied through the tip line of each channel and the current value applied through the ring line are detected. For this purpose, Rtf1 of the resistance applied to the tip line shown in FIG. The voltage at both ends of is connected to the input terminal of the LFDC 102, and the voltage at both ends of Rrf1 is connected to the other input terminal of the LFDC 102 among the resistors applied to the ring.

For this input signal, the LFDC 102 is composed of a differential amplifier 21, a low pass filter 22, and a comparator 23, as shown in FIG. 2, and as described above, the ring current and the tip wire current. The value is detected, and when the detected current value is equal to or greater than the bias voltage, it is operated to determine that a hook-off state due to an abnormal state has occurred.

That is, the differential amplifier 21 is a means for detecting the voltage difference between the tip line and the ring line, and one side contact TIP on the line Rtf1 and the tip side and one side contact RING on the line Rtf1 and the ring side are connected to the (-) input terminal. And a difference between the voltage applied through the two input terminals in a state in which the contact RF on the ring line between the other side of Rtf1 and the corresponding SLIC (101, 111, 121) is configured to be connected to the (+) input terminal. The difference detected at this time is hardly present at the normal hook-off. However, when hooked off due to ground or cross on the line, a difference occurs between voltages applied through the two input terminals. The voltage difference detected through the differential amplifier 21 is transmitted to the low pass filter 22.

The low pass filter 22 attenuates the AC component of the voltage difference transmitted from the differential amplifier 21 and outputs it at the voltage level of the DC component. The output signal is sent to the comparator 23.

The comparator 23 compares the bias voltage for current limit control with the voltage difference transmitted from the low pass filter 22, and outputs the result data of determining the abnormality on the line. That is, when the voltage difference transmitted from the low pass filter 22 is larger than the above-described bias voltage, the comparator 23 outputs the H level signal, which indicates that the line is in an abnormal state. On the other hand, when the voltage difference transmitted from the low pass filter 22 is smaller than the above-described bias voltage, the comparator 23 outputs the L level signal, which indicates that the line is in a normal state. The logic level of the output signal of the comparator 23 according to the steady state and the abnormal state may be set differently at design time. The bias voltage set in the comparator 23 is set in consideration of the tolerance as a threshold. The signal output from the comparator 23 is transmitted to the corresponding buffer of the buffering means 130 as LFD0 result data.

On the other hand, the SLIC (101) measures whether the current applied through the tip wire and the current flowing through the ring wire is the same as in the prior art, and if it is not the same as the measurement result, it is determined as the hook off state, if the measurement result is the same Preferred by the output through the SHD output stage. The output SHD0 signal is transmitted to the corresponding buffer 131 of the buffering means 130.

In addition, through the line monitoring unit 110 and 120 corresponding to the subscriber connected via CH 1 to CD N, the respective SHD and LFD are detected and transmitted to the corresponding buffer provided in the buffering means 130 as described above. .

The buffering means 130 has a buffer capable of storing information in units of 8 channels so as to store all N SHDs and N LFD signals transmitted from the line monitoring units 100, 110, and 120, and buffers the applied SHDs and LFDs. Do this.

For this purpose, each input of the buffers 131, 132 and 133 for storing SHD information in units of 8 channels and the buffers 134, 135 and 136 for storing LFD information in units of 8 channels is provided with respective SHD and LFD signal output terminals of the line monitoring units 100, 110 and 120. It is connected so as to correspond one to one. That is, SHD signals corresponding to CH 0 to CH 7 are connected to be transmitted to the first buffer 131, and SHD signals corresponding to CH 8 to CH 15 are connected to be transmitted to the second buffer 132, and CH N SHD signals corresponding to -7 to CH N are connected to be transmitted to the N / 8 th buffer 133. The LFD signals corresponding to CH 0 to CH 7 are connected to be transmitted to the (N / 8 + 1) th buffer 134, and the LFD signals corresponding to CH 8 to CH 15 are connected to the (N / 8 + 2) th buffer. LFD signals corresponding to CH N-7 to CH N are connected to be transmitted to the (N / 4) th buffer 136.

The SHD information connected as described above and stored in the buffers 131 to 133 are sequentially read by the read control signal provided from the SHD data read control unit 140 and transmitted through the data bus. That is, the SHD data reading control unit 140 reads the SHD information of the eight channel units stored in the N / 8th buffer 133 sequentially from the SHD information of the eight channel units stored in the first buffer 131. Provide a read control signal.

In addition, the LFD information stored in the buffers 134 to 136 is read in units of 8 channels by the read control signal provided from the LFD data read control unit 150. The LFD data read control unit 150 provides a corresponding read control signal so that the LFD information of the eight channels stored in the buffer in which the LFD information is stored is read so that the LFD information can be transmitted through the data bus. In this case, the active state of the SHD means a hook off state.

As described above, the present invention automatically monitors the hook-off state and abnormal state of the line by using current values flowing in the ring line and the tip line of the subscriber line, and whether the hook-off state is caused by the line abnormality is normally generated by the subscriber. By notifying the operator in real time, there is an advantage in that the subscriber service can be further improved by allowing the operator to take a prompt action in case of a hook-off due to an abnormal track.

Although the present invention has been described as the above-described embodiment, those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

Claims (6)

In an all-electronic switch system in which a telephone circuit is formed by using a tip line and a ring line during an exchange period of each subscriber, the voltage of the first predetermined section on the tip line and the second on the ring line for each subscriber Voltage difference detecting means for detecting a difference between voltages of a predetermined section; Discriminating means for comparing the voltage difference detected by the voltage difference detecting means with a predetermined bias voltage to determine whether there is an abnormal state of the corresponding line for each subscriber, and outputting a discrimination result signal to the exchange side; Subscriber line interface for outputting a hook-off status signal to the switchboard by detecting whether the corresponding subscriber channel has been normally hooked off by using the amount of current flowing on the tip line and the current flowing on the ring line for each subscriber. Automatic line detection device comprising a circuit (SLIC). The apparatus of claim 1, wherein the automatic line sensing device is output from buffers for storing the hook-off state signal output from the subscriber line interface circuit SLIC allocated to each subscriber in units of 8 channels and from the discriminating means. Buffering means for storing the information output from the subscriber-specific discrimination means and the subscriber-line interface circuit (SLIC), comprising buffers for storing an abnormal state signal of a line for each subscriber in units of 8 channels; And a read control signal for sequentially transmitting a hook-off state signal of each channel stored in the buffering means to the switch in 8-channel units by a mode selection signal and an address signal transmitted from the switch. Control unit; A second read control section for providing a read control signal for transmitting an abnormal state presence signal of a line of each channel stored in the buffering means to the exchange in units of 8 channels by a mode selection signal and an address signal transmitted from the exchange; Automatic track monitoring device comprising a further. The buffer of claim 2, wherein the second read controller is configured to store an abnormal state signal of a line corresponding to a channel determined as a hook-off state when the second read control unit reads the abnormal state signal of the line stored in the buffering means. And the read control signal is provided so that the read mode is sequentially controlled. The low voltage filter of claim 1, further comprising a low pass filter for low-pass filtering the voltage difference detected by the voltage difference detecting means to a level suitable for determining by the determining means. Automatic track monitoring device characterized in that. 5. The automatic detecting apparatus as claimed in claim 4, wherein said detecting means comprises a differential amplifier for differentially amplifying a voltage of a first predetermined section on the tip line and a voltage of a second predetermined section on the ring line to obtain the voltage difference. Track monitoring device. 6. The differential amplifier of claim 5, wherein the voltage between the first predetermined section on the tip line and the ring line and the voltage of the second predetermined section on the line are applied to the voltage across the predetermined resistor on the corresponding line. Automatic line monitoring device, characterized in that for configuring the connection state of the input terminal.