JPS62274824A - Swiching device for communication line - Google Patents

Abstract

PURPOSE:To reduce remarkably the memory capacity and to improve the reliability at core line switching by providing a static characteristic measuring means measuring the static characteristic of the 1st and 2nd variable resistive elements, a dynamic measuring means and a switching CONSTITUTION:The titled device consists of the static characteristic measuring means 12 with simple circuit constitution measuring each currentresistance characteristic of 1st and 2nd photocoupler type variable resistive elements 6b, 10b discretely in a spot way at a proper measuring interval and storing it in a prescribed memory 2 under the control of a CPU 1, a dynamic characteristic measuring means 13 checking whether or not the specific control function to the variable resistive elements 6b, 10b obtained by the result of the static characteristic measurement is used for the actual core line switching, and a core wire switching means connecting the core wire switchingly to the variable resistive elements 6b, 10b while adjusting the resistance according to the control function after the end of check. Since the expected resistance between spot current-resistance characteristic data stored in the memory is realized while the resistance is calculated minutely and smoothly by a CPU based on the said data, the memory capacity is reduced remarkably.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention [Field of Industrial Application] This invention provides a method for switching communication lines without affecting communication on the existing communication line to be switched. The present invention relates to a multi-pair communication line switching device that can switch one or more communication lines from an existing line to a new line.

[Prior art] Conventional fiber switching involves, for example, cutting off the existing core after confirming that the existing core to be switched is not in use.
There have been methods of connecting a new core wire, and methods of connecting a new core wire directly to an existing core wire and then connecting the existing core wire when electrical continuity is established.

However, the previous method cannot be applied when the core wire is in use. In addition, in the latter method, the transmission characteristics such as the balance of the communication line will be greatly disrupted the moment the existing core wire is connected to the new core wire, so if it is a data line such as a non-telephone digital line, the code An error occurs, which becomes a data error and causes communication to be interrupted.

Therefore, when switching data line fibers, a work standard has been established in which communication is temporarily stopped, then the newly installed fiber is switched, and the condition of the communication line after switching is monitored. The difficulty of implementing such a switching method has increased as the number of devices has increased.

In view of these problems, as a means of switching from the existing core to the newly installed core without affecting the communication of the existing core in use, a communication line system described in JP-A-60-180223 has been developed. Many-to-continuous switching systems have been proposed.

This multi-pair continuous switching system uses a connector with a structure that allows electrical continuity with the communication line to be extracted from the outside, the connector is installed on the communication line, and the continuity probe is connected to the connector. A method is used to obtain electrical continuity from the communication line through the connector.

Based on the configuration diagram of FIG. 4 and the configuration diagram of the core switching section in FIG. air circuit p
V, and the first switching circuit has a first . A second core switching section is connected to the second switching circuit, and a third core switching section is connected to the second switching circuit. A fourth core switching unit is installed, and the first, second and third . Each of the fourth resistance conversion sections has a terminal group (T+, T2) connected to the existing line.

(T+', T2') and (T5, T6 >,
(Ts'.

■6') and the terminal group (T3) that connects to the new line.

(T3'), (T4>, (T4'>) are provided, and the terminal groups (T, T+'), (T2, T2') and (T
s, Ts'), (T6, Te') on both sides of the switching point of the existing communication line (T3.T3'>).

Connect (T4, T4') to both ends of the new line,
Said 3rd. The fourth core switching unit, the existing and newly installed communication lines, and the first. The reference signal from the signal transmitter is connected to the signal receiver via the second fiber switching unit and the air circuit, and the first control unit and the second control unit are operated. In a communication line switching device for switching a newly constructed line, each of the core switching units is connected to one of the plurality of core pairs of the existing line.
A first switch that selects a fiber pair, a second switch, a third switch that selects one fiber pair from a plurality of fiber pairs on the new line, and a third switch that selects one fiber pair between the cutting points of the existing line. A fourth switch that can short-circuit (ON) or open (OFF) a pair of wires, a fourth switch that can short-circuit (ON) or open (OFF) any one core pair between the existing line and the new line, and the existing line. Any single wire pair short-circuit between newly installed lines (
A fifth switch that can be turned ON) or open (OFF>OFF), and a sixth switch that can be switched to the second switch or the third switch.
A switch, a seventh switch that switches a signal from an external circuit to the first switch and the sixth switch, and a resistance converter that can reduce the resistance value from a high resistance value to a low resistance value are provided between the first switch and the sixth switch. , the fourth switch is short-circuited, the fifth switch is opened, and an arbitrary single-core wire pair is selected from the existing line and the new line, and the switch is inserted between the first switch and the third switch. The resistance converter is reduced from a high resistance 1ift to a low resistance value, and then, in the fifth switch, the contact that is electrically connected to the arbitrary core wire pair is short-circuited, and the fourth switch is
3, the contact point electrically connected to the arbitrary one-core wire pair is opened, and the resistance converter inserted between the first switch and the second switch that selected the arbitrary one-core wire pair is increasing the resistance value from a low resistance value to a high resistance value, and transmitting the signal to a single core wire pair that is electrically connected to the first switch and either the second or third switch, and is electrically connected to the first switch and either the second or third switch. transmits an alternating current signal from the signal transmitting section, performs synchronous detection using the alternating current signal and a reference signal from the signal transmitting section in a synchronous detector of the signal receiving section, displays the detected output on a display, and displays the detected signal on the selected one. While monitoring the fiber pairs, the detection output is input to the first control section, and the above-mentioned control is carried out for the plurality of fiber pairs of the existing line and the new line, and the plurality of fiber pairs of the communication line are controlled. The automatic switching and the change in the resistance values of the plurality of core wire pairs are realized by a resistance change circuit using a photocoupler as shown in FIG.

Next, the above-mentioned conventional embodiment will be explained in more detail.

FIG. 4 is a block diagram of an embodiment of the multi-pair continuous switching system for communication lines according to the present invention.

In the figure, the same reference numerals as in Fig. 5 indicate the same parts, the same parts,
Compatible parts are shown.

In the figure, l-1oj (j = 1 to 6) is a continuity probe, which has the function of providing electrical continuity between multiple core pair switching devices MC+ + MC2 of the existing line PO or the new line PN. The core switching unit RT+ (RT+'
) and RT2 (RT2') terminal group 4-1 to T
6 (T+' to T6').

In this invention, in particular, by using a connector having a structure that allows electrical continuity with a communication line to be taken out from the outside, attaching the connector to the communication line, and connecting a front conduction probe to the connector, A method of obtaining electrical continuity from the communication line through a connector is used.

It is also possible to use a method in which the conduction probe has a needle or a blade portion (2) and a method in which a communication line coating is connected to the side or the blade to obtain electrical continuity directly from the communication line.

Here, the terminal groups T1 to T6 and T+' to Ts' are capable of electrically connecting a plurality of core wires, and Tj and Tj' (j=1 to 6) constitute a pair.

In this embodiment, 1-b l-1gj is used for the conduction
(j-1 to 6) can obtain electrical continuity with n pairs of core wires, and each terminal group Tj (, j=1 to 6) is composed of n terminals.

Core switching parts RT+, RT+' and RT2, RT2
' is composed of a mechanical contact and a resistance converting section that controls the resistance value, and the resistance value between the terminal groups of each core switching section changes over time.

To perform switching, first connect continuity probes Hgj (j-1 to 4) at two locations d3 across the switching point x of the existing line PO.
) to establish electrical continuity with the existing line 1]0, and to establish electrical continuity with the new line PM using the continuity probe 1-ICIj (j=5 to 6).

In the switching device MC2, the signal transmitting unit Qc is a general oscillator, and transmits an AC signal A c and a reference signal R for synchronous detection.
outputs a balanced output. The level of the AC signal Ac is the same as that of the existing line P.
Although it is desirable that the culm be as small as possible so as not to affect the communication of O, a culm degree of 150 dbm is sufficient in practice.

Prior to switching, it is desirable to transmit and receive the alternating current signal AC between the switching points and check the line number comparison, that is, the electrical continuity and polarity of the communication line. -For example, alternating current signal AC
The transmission/reception route is the wire switching unit RT2, R2'→terminal group Te+T6'→continuity probe 1'g4→continuity probe H (1+→terminal group T++T1'→core wire switching unit RT+, RT+') →An explanation will be given of the case where it becomes the signal receiving section RV.

The alternating current signal AC is transmitted and received by selecting one fiber pair of the existing line PO, and the transmission and reception is repeated for a plurality of fiber pairs. Selection and repetition of core pairs for transmitting and receiving alternating current signals AC are performed by core switching units RT+, RT2', and RT2. R-cho 2'
The core switching unit is controlled by control units CT+ and C7.
It is controlled by the drive signal SC output by 0. Here, when the control unit CT+ of the switching device MC+ outputs the drive signal SC, it also outputs the control signal CR, and the control signal CR is sent to the empty line PV via the transmitter S, and the switching device fW,
In MC2, the receiver R receives the control signal OR' from the transmitter S, and the control signal CR is input to the control section CT2. Here, since the reference signal RF is also transmitted and received along with the control JI3CR' on the empty line Pv, the receiver R has a function of receiving only the control signal CR'.

The alternating current signal AC is connected to the terminal FJTs, T5' → continuity probe HO3 → continuity probe 1''g2 → pancreatic group T
2. T'2' and terminal group Ta, T4' → Continuity probe H (Is → Continuity probe t-1 (Is → Terminal group T3.13'), transmission and reception is performed between switching device MC+ and MC2 in the same manner as above. be done.

When the alternating current signal AC is input to the signal receiving section RV, the signal receiving section RV converts the alternating current signal AC to the synchronous detector shown in FIG. The SD performs synchronous detection and outputs a detection output signal 01. For example, control to automatically transmit and receive the alternating current signal AC to a plurality of core pairs is possible by inputting the detection signal 01 to the control unit CT+.

Here, the route for transmitting and receiving the alternating current signal AC can be set arbitrarily.

Next, the process moves to core wire switching. The terminal group T+ to T2. T
I'~T2', T5~T6, TS'~T6'
short circuit (ON), T+~T3, T+'~T3',
T4-T6. ■ Connect the core switching sections RT+, RT+', RT so that the state between 4' and T6' is open (0 "1:").
2, control RT2'. Thereafter, at the switching point X, electrical continuity of the existing line po is interrupted and covered.

Here, if a transmission signal is flowing from A to B on the existing line Po, the flow of the transmission signal is A → Continuity probe Hg+ → Terminal group T+, T+ ' → Core wire switching section RT+
, RT+'→terminal group T2, T2'→continuity probe H (12→continuity probe H(]3→terminal group Ts
, Ts'→core switching section RT2, RT2'→terminal group T6. T6'→continuity probe Hg4→B.

After that, the core switching parts RT+, RT+', RT2
, RT2' is operated. Each core switching section RT+
.

The operations of RT+', RT2, and RT2' must be the same so as not to deteriorate the balance of the existing line PO. Each core switching unit RT+, RT+' RT2
, RT2' after the operation is completed, the flow of the transmission signal is as follows: A→continuity probe HO+→terminal group T+, T
+ '→Core switching section RT+, RT+'→Terminal group T3
, T3' → Continuity probe l-1 (is → Continuity probe HQ6 → Terminal group Ta, T4' → Core wire switching section RT2, RT2' → Terminal group Te, Te' →
Continuity probe H (+4'B roars.

The fiber switching is performed one fiber pair at a time, and selection of the fiber pair to be switched and repetition for a plurality of fiber pairs are automatically and sequentially performed under the same control as the transmission and reception of the target signal AC. Ru.

Further, even during and after the operation of the core switching section, the alternating current signal AC is transmitted and received along the same route as the transmission signal, so the detection output signal 01 of the signal receiving section RV determines the path of the transmission signal. It is possible to monitor

FIG. 5 shows an embodiment of the core switching section RT+.

However, the core switching parts RT+, RT+', RT2,
Since the configuration and operation of RT2' are all the same, the description will be given below by taking the core switching unit RT+ as an example.

In FIG. 5, SR is a terminal, which is connected to the signal receiving section RV in the switching device MC1 and to the signal transmitting section OC in the switching device MC2.

Before switching, when transmitting and receiving the control signal AC, each contact of the switches SWa and SWs is opened 1.
-ru. For example, terminal t11 of terminal group T1 (1≦i≦n
) to receive the alternating current signal AC, the terminal tri
→Switch SW+(f)→Switch 5W7(1)→Terminal SR route is selected. By changing the contact point of the switch S W + from 1 to n, n paths can be selected. Similarly, in the case of the terminal t21 of the terminal group T2, the terminal t21 → switch SW2 (i) → switch 5W6 (1) → switch 5W7 (2) → terminal SR, and in the case of the terminal t3i of the terminal group T3, the terminal t31 → Switch SW3 (i) → Switch 5We (2) → 5W7 (2
) route is selected. Here, switch SWj (
j=1 to 5) can be configured with general relays.

By selecting the above-mentioned routes, it is possible to confirm the electrical continuity and polarity of the route through which the transmission signal flows within the communication line, conductive clip, and switching device. However, this confirmation operation is an operation for increasing the reliability of fiber switching, and can be omitted.

After the confirmation operation is completed, the electrical continuity of the existing line between the terminal group T1 and the lower terminal group 2 is cut off. At this time, all the contacts of the switch SW4 are shorted (ON>), all the contacts of the switch SWs are opened (OFF), and the resistance converter RC between 8 and 5 is opened as shown in Figure 3. Therefore, the path of the transmission signal flowing on the existing line is terminal group T1 → switch SW4 → termination group T2.
It is.

Next, switching of the communication line connected to the i-th terminal of the terminal group will be specifically explained. The state of the switch contacts before the start of the switching will be described. In the switch SW4, contacts #1 to #1-1 are open (OFF) and contacts #1-4tn are short-circuited (ON>).
For s, contacts #1 to #i-1 are shorted (ON), and contacts #1 to #i-1 are shorted (ON).
#n is open (OFF). In addition, switch SW+
, SW2 and SW3 are set to i, and the contact of switch SW6 is set to 2. a- of resistance converter RC
Since the terminal between b is currently open, the transmission signal path is from terminal tri to switch SW4 (tti) to terminal tr.
It becomes i.

Thereafter, as will be described later, the resistance value between a and b of the resistance converter RC decreases from infinity to near 00, and after the resistance value changes, the contact #i of the switch SW s is short-circuited (ON). Thereafter, the contact of the switch SWs is set to 1, and then the contact #1 of the switch SW4 is opened. At this time,
The resistance value between 8 and 5 of the resistance converter Rc is around OΩ,
After the operation of switch SW4 ends, it increases to infinity. Here, it is desirable that the decrease and increase in the resistance value between a and b change continuously in order to reduce the influence on the transmission signal.

As a result, the existing line p
□-+terminal t+i-+switch SW4 (#t) → The transmission signal that took the route of terminal t21 is the existing line P.

→Terminal t+ i → Switch 5Ws (#i) → Terminal t3
i→The route is switched to the newly constructed line PN.

Furthermore, if the contact point of SW y is set to 1 while the resistance converter RC is in operation, it is possible to always receive the reference signal AC, so there is no electrical continuity with respect to the communication line to be switched. and polarity monitoring.

FIG. 6 shows an embodiment of the resistance conversion section Rc.

In Fig. 6, PC is a F,tl'' coupler, which causes a current to flow through the light emitting diode LED on the input side to cause it to emit light, and when the light beam hits Cds on the output side, the resistance value of Cds changes.PS is a constant voltage source and always supplies constant voltage VB. Also, VS is a voltage generator and supplies voltage ES to resistor R3. The voltage generator vS can be configured with a counter circuit or a ROM circuit. It is possible.

The photocoupler requires control because the relationship between the current value flowing through the light emitting diode LED and the resistance value of Cds differs from element to element.

First, in order to perform control, the contact points of the switch SW s and the switch SW 9 are set to 1. The X point is the virtual ground point of the operational amplifier OP and x=OV, so if the current value flowing through Cds is ls, and the resistance values of Cds and resistor Rs are ROM and rS, respectively, then R is as follows: ROM=VB/ l Is 1=VB/(IEs
l/rs)=VB-rB/lEs1. Therefore, the resistor ROM on the output side of the photocoupler PC can be completely controlled by the voltage Es.

In the circuit shown in Fig. 6, when ES < OV,
The output of the operational amplifier OP becomes a positive voltage. transistor l
'-r is for current enhancement, and when the output of the operational amplifier OP becomes positive, the emitter voltage 0 increases in the positive direction. Here, the voltage VO is the transition value of the resistor Rf, If the current flowing through the light emitting diode LED, and the light emitting diode L.
If the forward voltage of ED is VO, then VO=■f −rf
-+-vo, and the voltage value VO is written into the memory circuit MR. Memory circuit MR can be configured with a RAM circuit.

As shown above, depending on the voltage value ES, hook 1 to cover P
The resistance value ROM on the output side of C and the current value If flowing to the output side of hook 1 to cover PC are determined as one.

After the control is completed, the contacts of the switches S W a and S W 9 are set to 2, and the voltage value vO is read from the memory circuit MR. As a result, a current lr flows to the input side of the photocoupler PC, and the resistance value on the output side changes as set during the control. The change in the resistance value ROM can be arbitrarily set depending on how the voltage value ES is applied.

FIG. 7 shows an embodiment of the signal receiving section Rv.

In FIG. 7, DA is a differential amplifier, the reference signal R[ is inputted from ○, and the alternating current signal AC is inputted from P. f3F is a bandpass filter. Reference signal R [
The bandpass filter i! SBF is for separating the control signal CR.

Further, FS is a phase shifter. It is desirable that the phase shifter Fs is adjusted so that the detection output of the synchronous detector SD is maximized. LF is a low-pass filter, MT is a display, and display MT displays the detection output of the synchronous detector SD.

Here, if there is no need to display the detected output, the display MT can be omitted.

In this example, the frequencies of the alternating current signal AC and reference signal RF are set between 3300H2 and 35001-12 (7), and the sending levels of the alternating current signal AC and reference signal R are -60 dbm and -50 dbm, respectively. The signal speed on the AC communication line is 200 Kb/s
When the digital signals are sent to the existing line port, the core switching parts RT+, RT+',
It has been confirmed that the digital signal path can be monitored before, after and during the operation of RT2 and RT2'.

[Problems that the invention attempts to solve]

(1) What is the control voltage Vo and the resistance value of the photocoupler PC?
There is a one-to-one correspondence, and in the conventional method, the photocoupler PC is controlled using the control voltage VO itself stored in the memory, so it achieves minute (smooth) and highly accurate resistance changes and reduces the impact on communication. In order to suppress this as much as possible, A/D conversion technology with high resolution and precision and an enormous memory capacity due to the increase in the number of measurement points are required.

(2) Control of the photocoupler PC depends on the characteristics of the operational amplifier OP itself, and there is no function to check the resistance value of the photocoupler PC, so if the operational amplifier OP becomes defective, it is impossible to control the resistance value. There is a risk that Furthermore, the characteristics that occur during actual switching of a photocoupler type variable resistor may differ from the values measured in advance due to the effects of transient characteristics, etc., and transmission characteristics such as line balance may often be disrupted. Therefore, there is a need to measure the current-resistance of a variable resistor by simulating the switching state during actual switching.

[Means for solving problems]

The present invention has the following features: 1. A second photocoupler type variable resistance element is provided on the sending side and a receiving side respectively, and these photocoupler type variable resistance elements are connected and inserted into the switching part of the communication line core wire, and the resistance of the variable resistance element is By changing (increasing or decreasing) the value finely and smoothly while keeping both values the same, we can gently change the transmission characteristics of the communication line, and this allows non-telephone communication such as data communication. A communication line switching device that reduces the influence on system transmission as much as possible, wherein each current of the first and second photocoupler type variable resistance elements -
Static characteristic measurement with a simple circuit configuration in which resistance characteristics are measured discretely at appropriate points, that is, at appropriate measurement intervals, and relatively coarse data is collected and stored in a predetermined memory. and to obtain a desired current-resistance characteristic that is even denser than the spot-like current-resistance characteristic data stored in the memory and obtained by the static characteristic measuring means. While calculating the control function (more continuous and smooth current-resistance characteristic) that interpolates between each point using c, p, and u,
1st. Calculation that the photocoupler type variable resistance elements each have the right resistance change rate required at the time of actual core wire switching so that the realized resistance values of the second photocoupler type variable resistance elements take the same value. The resistance value is realized according to the control function that has been set, and then the first . It is verified whether the variation in the resistance value of the second photocoupler type variable resistance element is within an allowable range that does not adversely affect the communication line, and thereby each variable resistance obtained from the static characteristic measurement results is verified. A dynamic characteristic measuring means for checking whether the element-specific control function can be used for actual fiber switching, and also under the control of c, p, and u.
A core wire switching means is provided for selecting a core wire to be switched from among the target multi-pair lines, and switching and connecting the core wire to the variable resistance element while changing the resistance according to the control function after the completion of the above-mentioned check. It is characterized by

[Effect]

According to this invention, the expected resistance value between each spot is calculated finely and smoothly using c, p, and u based on the spot-like current-resistance characteristic data stored in the memory. Compared to the method of memorizing all the current data corresponding to the resistance value to be achieved, the memory I■ can be significantly reduced. J determined by the current-resistance characteristics of each discrete variable resistance element
: It is possible to check whether the variation in the resistance value of each variable resistance element realized by the smooth characteristic, that is, the control function, is within an allowable range.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a schematic configuration of an embodiment of the present invention.

FIG. 2 is a schematic connection diagram of the same embodiment.

FIG. 3 is a time chart showing the open/close states of each relay contact during core wire switching.

First, the overall configuration of this switching device will be schematically explained.

In FIG. 1, fiber switching adapters Aa and Ab are connected to both sides of a switching point 14 that is scheduled in the middle of the pair of wires Ll and L2 in the existing fiber 10 that is to be switched among the communication lines. and provides electrical continuity to the outside. Pair L+ of newly installed line 20.

For L2 as well, a core switching adapter, Ac, is connected to the switching planned position. Eighty of these adapters.

The Ab and Ac mechanisms and the connection switching method using them are detailed in Japanese Patent Application No. 145087/1987, so a detailed explanation will be omitted.

Connection lines are output from each of the adapters mentioned above to the switching device 30.

The configuration of this switching device includes a relay circuit section 31, a switching section 32,
It consists of a wire number confirmation section 33, a transmission section 34, a CPU section 3, and 5.

The relay circuit section 31 has a plurality of right contact relays, and the switching section 32 has a photocoupler type variable resistance element (similar to the conventional example).
However, the circuit configuration is relatively simple), a static characteristic measurement unit for measuring the current-resistance characteristics of the variable resistance element, and a static characteristic measurement unit based on the discrete current-resistance characteristics obtained from the static characteristic measurement unit. When a fine and smooth resistance change is realized under the calculation of c, p, and u, and at the same speed as the actual switching, the variation in the reproduced resistance value of the paired variable resistance element is It consists of an unbalance measuring unit to check whether the balance is within the permissible range.

The line number confirmation unit 33 is connected to the existing line 10 and transmits and receives a minute signal that does not affect communication between stations at the other end,
Perform wire number comparison. The transmission section 34 communicates between the stations at the other end for comparing incense sticks via an empty circuit 37.

The CPU unit has the function of controlling the above-mentioned switching operation in an integrated manner, and performs static characteristic measurement, unbalance measurement, data processing necessary for these measurements, and also has the function of sequentially performing core switching connections by switching relay contacts. has.

Next, this embodiment will be explained in more detail based on FIG. In this diagram, code 1 is the CPU (central processing unit)
, 2 is a memory consisting of a ROM in which programs for control function calculations and a series of sequential operations are stored, and a RAM mainly for storing static characteristic data. 3
is a photovoltaic plastic unit, which includes a D/8 (digital/analog) converter 4 for capturing voltage data corresponding to the resistance value of the variable resistance element, and a current corresponding to the output voltage of this D/A converter 4. It is composed of a V/■ (voltage/current) conversion circuit 5 that outputs I, and a photocoupler 6 (variable resistance element) driven by this V/I conversion circuit 5. LED-6a through which the above-mentioned current
ds-6b. A photocoupler unit 7 has the same configuration and function as the photocoupler unit 3, and is composed of a D/A converter 8, a V/I conversion circuit 9, and a photocoupler 10.

SW+ ~SW7.1+, SL2.3a t, Sb
i.

3e i, SNi, Sci (where i is the switching core logarithm) are turned on/off sequentially by CPU i.
The switch is driven off, and the connection state indicated by a solid line indicates a non-energized state.

12 is a static characteristic measuring unit, which includes a resistor 12a and a Δ converter that converts the voltage across the resistor 12a into digital data.
/D (analog/digital) converter 12b. In addition, in this unit 12, the terminal T
I1. TI2 are terminals to which voltages +V and -V are applied, respectively. Reference numeral 13 denotes an unbalance measuring unit, which is composed of an amplifier 13a and a comparator 13b. In this case, the comparator 13b compares the output of the amplifier 13a with a constant voltage VK, and the absolute value of the output of the amplifier 13a is determined by the voltage VK.
If the value is smaller, the signal is ``0'', and if the value is larger, the signal is ``1''.
'output each signal. The output of this comparator 13b is outputted to the pass line 1a of the CPU 1 via the interface circuit 14. Note that VK is a value determined experimentally. In addition, the unit 13 has power supplies of -1-V and -■, and connects terminals TI3 and TI4 to connection lines, respectively.
Voltage elements V and -V are applied.

Next, the operation of the switching device having the above configuration will be explained. Prior to cable switching, wire number comparison is performed.

This means that SWe, SW+, 3a i (1≦i≦1
0) is turned on, the incense stick comparison unit l~ is connected to the existing core wire via the adapter Aa, and a minute signal is transmitted and received between the stations at the other end to perform incense stick comparison.

Once the incense stick control is completed, the SWa, SW+, Sa
i is turned off, and the characteristics of the photocoupler type variable resistance element are measured.

That is, before actual switching, this switching device goes through two modes: (1) static characteristic measurement mode and (2) dynamic characteristic measurement mode, and then shifts to cable switching mode.

Each mode will be explained in turn below.

■Static characteristic measurement mode This mode is a mode for measuring each static characteristic of the photocoupler 6.10.

In this mode, the CPU 1 first switches SW2-
+ and 5W2-2 are each turned on (state of broken line). As a result, one end of CdS 6b is connected to switch SW2-+,
Static characteristic unit 1 via SW5-+ and SW7-+
2 terminal To, the other end of CdS 6b is switch SW2
-2.8W6-+ is connected to one end of the resistor 12a in the static characteristic unit 12 via SW7-2. That is,
The CdS 6b and the resistor 12a are connected in series, and voltages +V and -V are applied to both ends thereof, respectively. Next, CPtJ
By sequentially outputting specific discrete data to the D/A converter 4, l is set to 0.05, for example, to L E D 6a.
A, 0.1 A, O, , 15 A, . Here, each data taken into the memory 2 indicates the resistance value of the CdS 6b when each of the above Ii currents is applied to the LED 6a.

The above is the process of measuring the static characteristics of the photocoupler 6.

Next, the CPU 1 turns off the switches SW2-+ and SW2-2, and then switches 5W3-1. SW3-2,
SW7-+ and SW fur are each turned on (dotted line state). This connects the CdS 10b to the static characteristic unit 12. Next, the CPU 1 measures the static characteristics of the photocoupler 10 in the same manner as described above.

■Dynamic characteristic measurement mode In this mode, CPU1 first switches switch 5W2-
++2-2+5W3-++3-2,5Ws-+,s-2
．． 3Ws-+ and e-2 are each turned on, and the other switches are turned off. As a result, CdS 6b and 10b are connected in series, one end of Cd56b is connected to terminal TI3 of unbalance measurement unit 13, and the connection point of CdS 6b and 10b is connected to the input terminal of amplifier i3a in the same unit 13.
The other ends of the CdS 10b are connected to the terminal TI4 of the unit 13, respectively. With this connection, CdS・6b.

Voltages -V and -V are applied across the series circuit 10b, and the voltage at the connection point of CdS 6b and 10b is applied to the comparator 13b via the amplifier 13a.

Next, the CPU 1 changes the resistance values of CdS 6b and 10b with the speed and smoothness required when switching cables. This resistance value change is performed while calculating a control function based on static characteristic data.

= 30- That is, first, the resistance values of CdS 6b and 10b are set to the maximum value. Specifically, CdS・6b.

Data such that the resistance value of 10b becomes the maximum value is output to the D/A converters 4 and 8, respectively. Next, CdS・6b, 10b
The value of the drive current is calculated such that the resistance value is slightly lower than the maximum value, and the resistance value is set based on this value. Similarly, the resistance values of CdS 6b and 10b are sequentially decreased. Next is CdS・6b.

The resistance value of 10b is gradually increased.

In the above process, each resistance value of CdS 6b and 10b must sequentially decrease/increase while taking the same value. When the values are sequentially decreased/increased while maintaining the same value, the output of the amplifier 13a is always O because the balance is maintained, and therefore the output of the comparator 13b is always a 110 I+ signal. However, due to reasons such as the fact that the current-resistance characteristics of photocouplers are actually nonlinear, static characteristics are determined using linear interpolation, and the response speeds of photocouplers 6.10 and 10 are different. CdS・6b.

A difference (unbalance) occurs in the resistance value of 10b.

If this unbalance increases beyond a certain level, it will cause a beep to disturb the transmission characteristics of the core wire when switching cables.
Negative effects such as errors occur.

Therefore, in the switching device shown in FIG. 1, the comparator 13b constantly compares the absolute value of the output of the amplifier 13a and the constant voltage VK, and when the absolute value of the amplifier 13a becomes larger than the voltage VK, That is, when the output of the comparator 13b becomes the "'1" signal, the CPU 1 displays this on the display section (path shown) and at the same time stops the measurement, or returns to measuring the static characteristics again.

As a result of the above measurements, if the resistance unbalance amount does not fall within a predetermined value, measures such as replacing the photocoupler 6.100 are finally taken. Note that the resistance unbalance amount is determined by data on the communication line, and is more likely to be determined experimentally.

The above is the process of measuring dynamic characteristics. Although a detailed explanation will be omitted, a function may be added to verify and overturn the resistance value itself realized by the control function during this mode.

■Cable switching mode This mode is an operation mode for actually performing cable switching, and is performed after the above-mentioned static characteristic measurement and dynamic characteristic measurement are completed.

The actual switching operation will be explained with reference to the time chart in FIG.

First, switch SW+, SW2 are OFF, Sai, S
With bi, Sc+, and SNi turned off, the switches 3ei are turned on all at once at time t1 in FIG. As a result, the switch Sei is inserted in parallel to each existing core wire at the switching point.

In this state, at time t2, the switching points 14 of all the core wires are cut at the same time. Then, the pairs of wires from No. 1 to No. + are sequentially switched to new core wires.

Note that since the connection is normally switched every 10 pairs, the number is set to 1-10.

Note that these operations are performed under the control of the 010 unit 35 while being synchronized on the A side and B side in FIG. That is, a switching device similar to that on the A side is prepared on the B side so that the same resistance change can be made.

(1) At time t3, switch Sat of pair N01 and switches SC1, SLl, and SL2 are turned on. As a result, each core wire L+ of the pair N011.

1-2, CdS 6a and 6b, which are variable resistance elements, are inserted in series between the adapter Aa and AC, that is, between the remaining side of the existing core wire 10 and one end of the new core wire 20. Become. The values of these variable resistance values are both set to the maximum value in advance.

(2) From time t3 to time t14, the resistance value of each variable resistance element is decreased. If the realized resistance values are not always equal, line balance will be disturbed.

(3) Time t when the resistance value of each variable resistance element becomes low resistance
4, turn on switch SN+ to short-circuit between adapter Aa and AC. As a result, the existing core 10 and the new core 2
0 is connected.

(4) Switch SC+ is turned OFF at time t5, while switch Sb+ is turned ON and SL + is turned ON at time t6.

Turn SL2 OFF. As a result, switch S l-1
By switching from the newly installed side to the existing side, CdS 6b and 6b are inserted between adapters Δa and Ab.

(5) In this state, turn off the switch Set at time t7.
In this case, the variable resistance element is inserted in series between the remaining side and the discarded side of the existing core wire 10.

(6) Increase the resistance value of the variable resistance element by +8 from time t7.

(7) At time t8 when the resistance value of the variable resistance element becomes high,
Turn off switches Sat and Sb+. This bundle and variable resistance element are connected to the existing core 10 and the new core ffA20.
The existing core wire 10 is separated from the remaining side and the discarded side. On the other hand, the AC adapter Δa, that is, the remaining side of the existing core wire 10 and one end of the new core wire 20 are connected to the switch S
The connection state is maintained by N+.

After the switching of the pair N01 is completed in this way, the switching of the pair N092 and subsequent ones is performed in the same manner. Then, at time t10 in FIG. 3, the existing side a5
and the newly installed multi-core wires (this connection is made by connecting connector halves (not shown) all at once), and at time t.
Switch SN+ to 5NI that connected the F center line to 11
Let O be OF I:. When the switching is completed in this way, the CPU section 35 and the like return to the initial state at time j+2, and the operation ends.

The above are details of the embodiments of the present invention. It goes without saying that in the cable switching process, it is desirable to change the resistance values of the CdS 6b, 6b as minutely (smoothly) as possible.

〔Effect of the invention〕

(1) Based on static characteristic data, c p u k:, J
:Since this method calculates a control function, it requires less memory to store data to realize minute resistance changes, compared to a method that stores all current values corresponding to the resistance value to be realized in memory. The amount can be significantly reduced.

(2) Since the circuit configuration is simpler than that of a resistance converter using an operational amplifier, the reliability of the system is improved.

(3) Before the actual wire switching, current-resistance measurement is performed using the dynamic characteristic measurement mode to eliminate premature imbalance, which improves reliability during wire switching3.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of the present invention, and FIG. 2 is a schematic diagram of the present invention.
Figure 3 is a schematic connection diagram of the embodiment; Figure 3 is a time chart showing the open/closed state of each relay contact before switching the core;
The figure shows a configuration diagram of a conventional multi-to-continuous switching system, Figure 5 is a configuration diagram of a core switching unit in a conventional example, Figure 6 is a resistance conversion unit, and Figure 7 is a signal receiving unit. L, +, l-2... Pair of wires to be switched, 1
...C, P, (J, 3.7...Photo power bra unit 1~.12...
...Static characteristic measurement unit 1, 13...Unbalance measurement unit, 6a, 10a --L
E D (light emitting diode), 6b, 10b...
...CdS (variable resistance element).

Claims (1)

[Claims] In a communication line switching device which has first and second photocoupler type variable resistance elements and which switches between an existing core wire and a new core wire by inserting these variable resistance elements into a switching section of the communication line, the first and second photocoupler type variable resistance elements 1. A static characteristic measuring means for measuring the static characteristic of a second variable resistance element, and measuring the first and second variable resistance elements so that their resistance values are equal based on the measurement results of the static characteristic measuring means. selecting a core wire to be switched from among the multi-pair lines; A communication line switching device comprising: switching means for switchingly connecting the core wire to the variable resistance element.