JPH10200632A - Line test equipment - Google Patents

Abstract

(57) [Summary] In a line test apparatus, an actual line switching state by a line switching circuit for switching and connecting a telephone line between a test unit and a receiving unit is surely monitored. SOLUTION: A reception unit for receiving an incoming call via a telephone line, a test unit ATP for testing a communication path to the reception unit, and a telephone line are connected to the test unit ATP from a connection state with the reception unit. Line switching unit SWP for switching to connection state
And a control unit CCP. The line switching section SWP performs line switching by relays LA and L having a plurality of switching contacts.
This is performed by using some of the switching contacts a0 and b0 of B. Control unit C
The CP receives instruction information for switching the line switching circuit 210 to the test section ATP side through a line different from the telephone line, controls switching of the line switching circuit 210, and switches contact points a0 of the relays LA and LB. , Bo, the switching state of the other switching contacts a1, b1 is detected via the monitoring port 222, and the line switching circuit 210 is detected.
Check the switching status of.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a line test apparatus suitable for use in testing special lines such as police lines and fire lines.

[0002]

2. Description of the Related Art Police and fire lines (Police and fire)
Fire Line) is also called a PF line, and is a special line from an exchange to a reception desk of a police station or a fire station.
When a general subscriber dials 110 or 119, the fire and police trunks of the exchange (Fire and Police)
(Police Trunk: abbreviated as FPT) is connected to the PF line, and a call is received at the nearest police reception desk or fire reception desk, and if a response is made, a telephone call is made.

[0003] A fire and police trunk (hereinafter referred to as FPT) is a one-way trunk to a police and fire reception desk or the like, and uses this FPT.
No.) and the following features that are not found in calls between general subscribers. -Even if the other party (reception desk) responds, analog subscribers do not receive reversal information. That is, since a single call is usually made from a public telephone or the like, a call can be made by pressing a button or the like. -Even if the subscriber ends the call (on-hook) from the call state, the line is maintained if the reception desk does not end the call. At this time, the line is not disconnected. -A subscriber can be called from the reception desk from the above line holding state (recall).

[0004] Police and fire lines have two lines: A line and B line.
It is a line type, and serves as both a communication line and a control line like an analog line of a telephone. The police and fire lines are classified into the following four systems depending on the difference in the signaling system.

[0005] Telephone system (AC system) This is similar to a normal analog subscriber, and the calling signal is C
It uses R (16Hz) and is used by both police and fire departments. The reception side is a general telephone and the earth (or battery:
(For recall), the function can be satisfied.

[0006] Police (DC) system This is used only by the police.

[0007] Fire (DC) method This uses only firefighting, and is different from the police (DC) method described above.

Fire ID system This is a system in which only firefighting is used, and in which a caller's identification number is transmitted as an ID from an exchange to a reception desk by an MF signal. The MF signal is used for inter-station use, and is used as a PB signal / D
Different from TMF signal.

In the case of a police or fire line as described above, the intended purpose cannot be achieved in the event of a failure in an emergency, so it is important to conduct a line test periodically as appropriate. . For this reason, conventionally, an actual telephone call was made to a police station or a fire reception desk for an appropriate test, and a test was performed to determine whether or not a normal operation was performed.

[0010]

However, actually performing a test by making a telephone call requires an operator on each of the test side and the reception desk side, and the test is time-consuming and troublesome. there were.

Therefore, an automatic line test system for automatically performing a test of a police / fire line has been considered. In this system, a line test apparatus equipped with a line switching circuit that switches from a reception desk side to a test unit side when performing a test is installed at a terminal of a police station or a fire station,
An automatic test control terminal for performing an automatic line test by remotely controlling this line test apparatus via a telephone network is provided.

When the test is actually executed by the automatic line test system, an automatic test control terminal
Instruct the line test equipment to start the test through a line separate from the police and fire lines. Then, the line test apparatus switches the police / fire line from the reception desk to the test section by the line switching circuit. Then, the test is performed between the test section and the automatic test control terminal through the police / fire line.

In this line test system, the line switching circuit normally performs switching using a relay. However, the actual contact operating state of the relay due to malfunction such as when a failure occurs in the drive circuit of the relay. May be incorrect. In such a state, the line test cannot be correctly performed, and the reception desk may not be correctly connected to the police / fire line after the test.

SUMMARY OF THE INVENTION In view of the above, an object of the present invention is to enable the above-described line test apparatus to reliably monitor an actual line switching state by a line switching circuit.

[0015]

In order to solve the above-mentioned problems, a line test apparatus according to the present invention includes a receiving unit for receiving an incoming call through a telephone line, and a test unit for testing a communication path to the receiving unit. And switching the telephone line from the connection state with the reception unit to the connection state with the test unit, and the switching is performed using a part of the relay contacts having a plurality of switching contacts. A line switching circuit, through a line different from the telephone line, receives instruction information for switching the line switching circuit to the test section side, and controls switching of the line switching circuit, and a part of the relay. A control unit for confirming a switching state of the line switching circuit based on a switching state of another switching contact that is driven in conjunction with the switching contact.

[0016]

According to the line test apparatus having the above-described structure, when the relay for switching between the telephone line and the receiving section or the test section is driven, the other switching contact driven in conjunction with the line switching contact is driven. The switching unit is monitored by the control unit to confirm the actual switching state. Therefore, it is possible to reliably monitor a malfunction state, such as when the relay of the line switching circuit is defective, and to surely perform the line test, and also to surely monitor the switching from the test state to the reception table. .

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a line test apparatus according to the present invention will be described below with reference to the drawings.
The example described below is a case where the present invention is applied to the above-described system for performing a line test on a police / fire line.

FIG. 2 is a diagram for explaining a system including the line test apparatus. In FIG. 2, reference numeral 1 denotes a terminal unit provided at a police station or a fire station, to which a plurality of police / fire lines 2 (hereinafter referred to as PF lines) are connected. The PF line is connected to an exchange 4 connected to a telephone network 5 via the aforementioned fire and police trunk (hereinafter referred to as FPT) 3.

On the other hand, P through a modem (modulation / demodulation circuit) 8
An automatic test control terminal 9 of the F line is connected to the telephone network 5 through the general line 7. The modem 8 also has a built-in NCU (network controller).

In the terminal unit 1, the PF line 2 is connected to the external connection terminal unit 11. This external connection terminal 11
Is connected to an external connection terminal unit 13 through a line test device 12 having a line switching circuit as described later. The external connection terminal 13 is connected to the manual reception board 14.

The line test apparatus 12 is connected to the modem 15
Is connected to the telephone network 5 via a general line 6 which is not a PF line. This modem 15 also has a built-in NCU (network controller).

The line test apparatus 12 normally connects the manual reception table 14 to the P by a line switching circuit provided therein.
The state is switched to a state of connecting to the F line 2. As will be described later, the line test apparatus 12 is transmitted from the automatic test control terminal 9 through the modem 8, the line 7, the telephone network 5, the line 6, and the modem 15.
Then, when the test start instruction arrives, the PF line 2 is disconnected from the reception board 14 and switched to the test unit in the line test apparatus 12. When the test is completed, the PF line 2 is switched from the test section of the line test apparatus 12 to the manual reception board 14 side.

Then, when the PF line 2 is switched to the test section of the line test apparatus 12, as described later,
Various line tests are executed between the automatic test control terminal 9 and the line test device 12 of the terminal unit 1 of the police station or fire department via the PF line 2. The test result is sent from the line test apparatus 12 to the automatic test control terminal 9 through the modem 15, the line 6, the telephone network 5, the line 7, and the modem 8, contrary to the test start instruction.

In this example, the line test apparatus 12 is configured as shown in FIG. That is, the line test device 12
Is composed of a line switching unit SWP, an automatic test unit ATP, and a control communication unit CCP.

The line switching unit SWP has a function of drawing a line under test in response to a test instruction from the automatic test control terminal 9 via the control communication unit CCP.

The automatic test unit ATP has a processing function of a called incoming / answering test, a call recalling test, a called destination restoration test, and a series of call connection tests.

The control communication unit CCP controls automatic test control such as a called incoming / answering test, a call recalling test, a called destination restoration test, a series of call connection test controls, test instructions, and transmission and reception of test results. It has a function of controlling communication with the terminal 9.

The line switching unit SWP includes a line switching circuit unit 21
And a relay control / monitoring unit 22. The line switching circuit unit 21 includes a line switching circuit 210 for each of the plurality of PF lines 2. In FIG. 1, # 1 line, # 2 line,..., #N line indicate line switching circuits 210 corresponding to the first, second,. Is shown.

As shown in FIG. 1, each of the line switching circuits 210 connects the A line and the B line of the PF line to each other.
Switching contacts a0 and b0 for switching between a state of connection to the external connection terminal unit 13 side to which the reception board 14 is connected and a state of connection to the automatic test unit ATP side of the line test apparatus 12.
It has. As these switching contacts a0 and b0, some of the contacts of relays LA and LB described later, each having a plurality of contacts, are used.

The relay control / monitoring unit 22 includes:
As shown as # 1, # 2,..., #N lines, a drive control / monitoring circuit 220 corresponding to each of the n line switching circuits 210 is provided.

Each of the drive control / monitoring circuits 220 is provided with two relays LA and LB having switching contacts serving as the switching contacts a0 and b0, and simultaneously driving these two relays LA and LB. A relay drive circuit 221 for performing the operation is provided. Relay drive circuit 221
Is supplied with a relay drive control signal from the control communication unit CCP.

In the case of this example, the switching contact a0 is connected to the relay L
A, and the switching contact b0 is a contact of the relay LB. When these relays LA and LB are not driven, the switching contacts a0 and b0 are connected to the external connection terminal 13 as shown in FIG. Side (break contact). When a drive current flows through the relays LA and LB through the drive circuit 221, the switching contacts a0 and b0 are switched to the automatic test section ATP side (make contact).

The relays LA and LB are provided with other switching contacts a1 and b1 which are switched in conjunction with the switching contacts a0 and b0.
The switching state of b1 and b1 is supplied to the control communication unit CCP through the monitoring port 222. In this example, as shown in FIG. 1, the monitoring port 220 is grounded via the switching contacts a1 and b1 in the switching state (break contact side) when the driving current is not supplied to the relays LA and LB. In the switching state (make contact side) when is supplied, the free end is set.

Therefore, if the relays LA and LB operate normally, when the line switching circuit 210 is switched to the reception board 14, the monitoring signal SVA at the contact a1 and the monitoring signal SVB at the contact b1 are both low. Level (“0”), and these are sent to the control communication unit CCP through the monitoring port 220. The line switching circuit 21
When 0 is switched to the automatic test section ATP side, the monitoring signal SVA on the contact a1 side and the monitoring signal SVB on the contact b1 both become high level (“1”), and these are sent to the control communication section CCP through the monitoring port 220. Sent.

The control communication unit CCP communicates with the monitoring port 22
The switching state of each line switching circuit 210 is monitored by the signals SVA and SVB from 0.

The automatic test section ATP includes a construction setting section 23,
And a line test unit 24. The construction note setting unit 23
This is for performing the work setting according to the above-described four methods for the F line. In the case of this example, the type of the PF line drawn into the terminal device 1 of the police station or the fire department is registered in the automatic test control terminal 9, and
From the automatic test control terminal 9, the line 6 and the modem 15
, The control communication unit CCP sends an instruction as to which type of PF line it is. The control communication unit CCP controls the work setting unit 23 according to the instruction, and controls the work setting according to the test instruction so as to perform the work setting according to the type of the PF line to be tested.

The line test section 24 performs a called incoming call / response test,
It has a trunk circuit that performs a call recall test, a called party restoration test, and a series of call connection processing. Further, in response to a command from the control communication unit CCP, the control unit generates various control signals in the automatic test unit ATP and returns an answer to the control communication unit CCP.

Next, with reference to FIG. 3, an operation sequence of a PF line test by the line test system having the above configuration will be described. FIG. 3 shows an automatic test sequence when the PF line system is a telephone system. In the following description of the sequence, a signal that is not particularly described through the modem is an FPT and the line test apparatus 12 or the FP
It is exchanged between the automatic test control terminal 9 and the line test apparatus 12 through T.

First, in a line test, a test start instruction command is generated from the automatic test control terminal 9. This test start instruction command is transmitted from the modem 8, the line 7, the telephone network 5-
The signal is sent to the control communication unit CCP of the line test apparatus 12 through the line 6-modem 15 and received. Control communication unit CCP
Analyzes the information in the instruction command regarding any one of the above-mentioned four methods for the PF line 2 from which the test is to be started, and then sets the work setting unit 2 of the automatic test unit ATP.
The control signal is sent to the third node, and the work setting according to the line type is performed.

Next, the control communication unit CCP sends a PF line designated by an instruction command of the plurality of PF lines 2 to the line test apparatus 12 side, so that the line switching unit S
The relay drive circuit 2 is connected to the relays LA and LB of the line switching circuit 210 corresponding to the designated PF line of the WP.
A drive current is passed through 21. Thereby, the relay L
If A and LB are driven normally, the switching contacts a0 and b0 of the line switching circuit 210 are switched to the automatic test section ATP side, respectively.

When the relays LA and LB are normally driven and the switching contacts a0 and b0 of the line switching circuit 210 are switched to the automatic test section ATP, respectively, the monitoring signal SVA from the monitoring port 222 and the monitoring signal SVA from the monitoring port 222 are switched. SVB becomes "1", and the line switching unit SWP
Sends this to the control communication unit CCP.

In response to this, if the monitoring signals SVA and SVB are both "1", the control communication unit CCP determines that the PF line to be tested has been correctly pulled in, and is provided in the control communication unit CCP. The line to be tested is displayed on a display unit (not shown). A display signal is also sent to the line switching unit SWP, and a line to be tested is displayed on a display unit (not shown) provided in the line switching unit SWP.

Although not shown in FIG. 3, if
As a result of reading the monitoring signals SVA and SVB by the control communication unit CCP, the monitoring signals SVA and SVB are not both at “1” and the PF to be tested
If the line cannot be correctly pulled in, the control communication unit C
The CP is connected via the modem 15 to a line 6 different from the PF line 2.
Is transmitted to the automatic test control terminal 9 through the terminal. As a result, for example, the test is interrupted.

As described above, when the line under test has been correctly pulled in, the automatic test control terminal 9
Make a call through the line. Then, FPT3 and P
If the F line is in the correct state, CR
(16 Hz) is detected by the control communication unit CCP through the automatic test unit ATP. If the call is not correctly detected, a command to that effect is sent to the automatic test control terminal 9 through the modem 15, and the test is interrupted there.

When the control communication unit CCP detects the CR correctly, the control communication unit CCP outputs a signal (RA = 1) of the stand response to the automatic test unit A.
It is sent to the automatic test control terminal 9 through the TP. Then, after transmitting the test circuit connection signal (TN = 1) to the automatic test unit ATP, the control communication unit CCP transmits a response signal to the automatic test unit AT.
It sends to the automatic test control terminal 9 through P.

Upon receiving this response signal, the automatic test control terminal 9 sends a PB signal representing the symbol [C] as a test call identification signal through the automatic test unit ATP to the control communication unit CCP.
Send to The control communication unit CCP transmits the reception result to the modem 1
5 and to the automatic test control terminal 9 through the line 6. For example, if the reception of the test call identification signal is erroneous, the test is stopped.

When the test call identification signal is correctly received, the control communication unit CCP sends a PB signal meaning a number "1" to the automatic test control terminal 9 through the automatic test unit ATP as a level measurement signal.

The automatic test control terminal 9 which has received this level measurement signal sends a PB signal meaning a symbol [D] to the control communication unit CCP through the automatic test unit ATP as a level measurement signal. The control communication unit CCP sends the reception result to the automatic test control terminal 9 through the modem 15 and the line 6. The automatic test control terminal 9 receives this and determines whether to continue or stop the test.

If the measurement level is correct and the test is to be continued, the control communication unit CCP sends a PB signal meaning the number "2" to the automatic test control terminal 9 through the automatic test unit ATP as a disconnection request signal.

When the caller performs a line disconnection operation,
The busy tone BT is sent to the control communication unit CCP through the automatic test unit ATP. The control communication unit CCP sends the reception result to the automatic test control terminal 9 through the modem 15 and the line 6. In this case, the automatic test control terminal 9 continues the test even if the reception result is NG.

Thereafter, the control communication unit CCP sends a recall signal to the automatic test control terminal 9 through the automatic test unit ATP.
When the caller, that is, the automatic test control terminal 9 side responds to this recall, a PB signal of the number “0” is sent to the control communication unit CCP via the automatic test unit ATP as a response signal. The control communication unit CCP sends the reception result to the automatic test control terminal 9 through the modem 15 and the line 6. The automatic test control terminal 9 receives this and determines whether to continue or stop the test.

When the test is continued, the control communication unit CCP
Sends the PB signal of the number “3” as a completion notification to the automatic test control terminal 9 through the automatic test unit ATP. Then, an instruction to release the test circuit is sent to the automatic test unit ATP, and thereafter, the control communication unit CCP sends a table disconnection (RA = 0) to the FPT 3 through the PF line 2.

Then, the control communication unit CCP stops energizing the relays LA and LB in order to switch the line switching circuit 210 from the automatic test unit ATP side to the reception board 14 side. As a result, when the relays LA and LB operate correctly, the switching contacts a0 and b0 return to the illustrated state, and the line switching circuit 210 switches to the manual reception board 14 side.

If the relays LA and LB operate correctly, the switching contacts a1 and b1 also return to the states shown in the figure, so that the switching state signals SVA and SVB both become "0". The control communication unit CCP receives and reads this, and confirms the release of the pull-in of the test circuit. And the control communication unit CCP
Sends a test line display release to the line switching unit SWP to release the display. Thereafter, the control communication unit CCP sends information on whether or not the line switching unit SWP has been correctly switched, and the test result to the automatic test control terminal 9 through the modem 15 and the line 6 and transmits the information of the one PF line. The test ends.

The above operation is performed for each of a plurality of PF lines that are drawn into the fire department or police station, and each PF line is checked.

[0056]

As described above, according to the present invention, in the novel automatic line test system as described above, the switching of the line switching circuit 210 for switching the connection between the receiving unit and the test unit for the line. As a contact, it is driven by using a part of contacts of a relay having a plurality of contacts,
By monitoring the switching state of the other contacts that are driven in conjunction with the partial contacts of the relay, it is possible to detect whether or not line switching has been performed reliably.

Therefore, it is possible to monitor so that the test is executed reliably and the line switching to the receiving unit is also executed reliably.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a line test apparatus according to the present invention.

FIG. 2 is a block diagram showing an overall outline of a line test system to which a line test apparatus according to the present invention is applied.

FIG. 3 is a diagram showing a test operation sequence of an embodiment of the line test apparatus according to the present invention.

[Explanation of symbols]

 2 Police / fire line 3 Fire / police trunk 6,7 Telephone line 8,15 Modem 9 Automatic test control terminal 12 Line test device 14 Manual reception desk 21 Line switching circuit 22 Relay control / monitoring unit 23 Work setting unit 24 Line Test unit 210 Line switching circuit 220 Drive control / monitoring circuit 221 Relay drive circuit 222 Monitoring port SWP Line switching unit ATP Automatic test unit CCP Control communication unit

Continued on the front page (72) Inventor Sugawara Upper 6-10-13 Nakanobu, Shinagawa-ku, Tokyo Inside Daiko Electric Manufacturing Co., Ltd. (72) Inventor Masaharu Hirano 3-9-1-2 Nishishinjuku, Shinjuku-ku, Tokyo Telephone Co., Ltd. (72) Inventor Akira Kaneko 3-2-1-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo Nippon Telegraph and Telephone Co., Ltd.

Claims (1)

[Claims] A test section for testing a communication path up to a reception section for receiving an incoming call via a telephone line; and changing the telephone line from a connection state with the reception section to a connection state with the test section. A line switching circuit for performing the switching by using a part of switching contacts of a relay having a plurality of switching contacts; and Receiving the instruction information for switching to
A control unit that controls switching of the line switching circuit and checks a switching state of the line switching circuit based on a switching state of another switching contact that is driven in conjunction with some of the switching contacts of the relay. A line test apparatus characterized by the above-mentioned.