JPH08149053A - Power line signal transmitting device - Google Patents

Abstract

PURPOSE: To attain the power line communication among the branch power lines which are wired from a trunk line via a breaker contained in a distribution bord. CONSTITUTION: The power line bridges 2a to 2c consist of the circuits which eliminate the power frequency bands and make the bands including the communication signals pass and are connected among paired branch power lines L1 to L10 which are branched from a trunk line L0 via the breakers 4a to 4j. The lines L1 to L4 connected to the bridges 2a to 2c are connected together via these bridges so that the power line communication is attained among the lines L1 to L4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal transmission device in a power line communication system for performing communication using a power line.

[0002]

2. Description of the Related Art A power line communication system for performing communication in a closed area such as in a store, a house, a building, etc. without using the closed area is already known. In this power line communication system, a signal is shielded from the closed area, a transmitter and a receiver are connected to the power line in the closed area, and communication is performed between the transmitter and the receiver via the power line.

[0003]

In the above power line communication system, it is premised that all the power lines are connected in the closed area. However, the power line is branched into a plurality of paths in the closed area, and each is connected to the main line by a breaker. The breaker attenuates a certain high frequency band of a communication signal even if it passes the low frequency power supply frequency band (50 Hz, 60 Hz), and cannot sufficiently pass the communication signal, so that accurate and satisfactory communication cannot be performed. Also,
The breaker is turned off and the communication path is disconnected, and communication by the branch power line including the breaker cannot be performed. Therefore, an object of the present invention is to provide a power line signal transmission device for a power line communication system capable of communicating even between power lines connected via a breaker.

[0004]

According to the present invention, a power supply frequency band composed of a high-pass filter, a capacitor, a photocoupler and the like is removed between two sets of power lines of a pair of power lines branched from a main line via a breaker. Then, a power line bridge of a circuit that allows a certain band of a communication signal to pass is connected to enable power line communication between two sets of power lines. In particular, in one store, one house, which is branched from the main line via the breaker of the distribution board,
When performing power line communication between power lines in a closed area such as one building, the number of breakers connected to the power line to be communicated in the distribution board is 1 from the above power line bridge.
The power line bridge is connected in series, and each pair of power lines branched from the trunk line via the breaker is connected to the pair of transmission lines between the power line bridges, and the series circuit of the power line bridge is connected. The remaining power lines are connected to the pair of transmission lines at both ends to enable power line communication between the branch power lines. Alternatively, one pair of transmission lines of each power line bridge is connected to a branch power line, and the other pair of transmission lines of each power line bridge is connected to another branch power line, respectively, to enable power line communication between the branch power lines. To do.

When the breaker is a single-sided breaker, one of the two pairs of transmission lines of each of the power line braids is connected to the same conductor, and the conductor is connected to the same conductor without passing through the breaker of the power line. By connecting the transmission line of the other side of each set to the other line connected to the breaker, the power line communication between the branch power lines is enabled.

The power line bridge is arranged in a housing having a pair of plugs, a pair of receptacles and a pair of power line connecting portions, and one set of the two pairs of transmission lines is the plug and the other set is the above. The power line connecting portion is connected to a receptacle, and the power line connecting portion is composed of a first connection unit connecting to the plug or one of the sets of the receptacle, a housing including a pair of plugs, a pair of receptacles, and a pair of power line connecting portions. The power line connecting portion has at least one or more second connecting single body connected to one set of the plug or the receptacle in accordance with the connection between the power line connecting portion and the plug or the receptacle in the first connecting single body. Connect in combination Connect a single plug and receptacle to connect between power lines. Further, the second connection unit is provided with a connection terminal connected to a plug or a receptacle not connected to the power line connection unit on the outer surface of the housing of the second connection unit.

In addition, the first connection unit and the second connection unit are provided with a third plug together with a pair of plugs, and a third receptacle together with a pair of receptacles. The third receptacle is electrically connected, and when the pair of plugs of one connection unit is connected to the receptacle of the other connection unit, the third plug and the third receptacle are also connected. Further, a connection terminal connected to the third plug and the third receptacle is provided on the outer surface of the housing.

[0008]

Since the power lines branched from the main line via the breaker are connected by the power line bridge of the circuit which removes the power supply frequency band and passes a certain band of the communication signal, the communication between the power lines via this power line bridge You can If all the power lines that are going to communicate between the power lines branched from the main line via the breaker are connected by the power line bridges, the power lines connected by the power line bridges in one store, one house, one building, etc. Power line communication can be performed in the closed area. Also in the connection between the power line and the power line bridge, by connecting the first connection unit and the second connection unit in combination, the connection between the two power lines and all the power lines in the closed region can be easily performed. You can

[0009]

1 is a block diagram showing a circuit configuration of a first embodiment of the present invention. In the figure, reference numeral 1 is one store, one house,
A distribution board for distributing electric power in a closed area of one building or the like, and a main line L0 of the distribution board 1 is connected to an external power line Lout via a main breaker 3. From main line L0 to breaker 4a-
The power lines L1 to L10 are branched to respective parts in the closed region via 4j, and the inside of the closed region is divided to supply electric power to the branched power lines L1 to L10. Further, in the present embodiment, the power line signal transmission device 2 having the power line bridges 2a to 2c whose number is one less than the number of breakers 4a to 4d connected to the power lines L1 to L4 to be communicated is provided. There is. A power line bridge 2a is connected between the branch power line L1 and the branch power line L2, and power line bridges 2b and 2c are connected between the branch power line L2 and the branch power line L3 and between the branch power line L3 and the branch power line L4, respectively.

That is, the power line bridges 2a to 2b of the power line signal transmission device 2 are connected in series, and both ends of the series circuit of the power line bridge and the transmission lines connecting the power line bridges are connected to the breakers 4a to 4d, respectively. It is connected to the branch power lines L1 to L4. In the example shown in FIG.
Transmission lines J1 and J2 of the power line bridge 2a are branched power lines L
1 and the transmission lines J3 and J4 are connected to the power line bridge 2b.
Branch power line L2 while being connected to the transmission lines J1 and J2 of
It is connected to the. The transmission lines J3 and J4 of the power line bridge 2b and the transmission lines J1 and J2 of the power line bridge 2c are connected to the branch power line L3, and the transmission lines J3 and J4 of the power line bridge 2c are connected to the branch power line L4. ing.

The power line bridges 2a to 2c remove the power supply frequency (50HZ, 60HZ) band, and have a band of a communication signal for power line communication (for example, 10KHZ to 500).
KHZ) and a high-pass filter composed of a capacitor C and a transformer T as shown in FIG. 2, a capacitor C, and a photocoupler Ph composed of a light emitting element and a light receiving element. The conventional power distribution board is not provided with the above-described power line signal transmission device 2, and when the breaker is included in the communication path of the power line communication,
Satisfactory power line communication was impossible or almost impossible.

However, in this embodiment, each branch power line is connected by a power line bridge, the power line frequency is insulated by the power line bridge, and the frequency band of the communication signal of the power line communication is passed. Power line communication can be performed between the branch power lines L1 to L4 connected by the bridge.
For example, in the case of performing power line communication by connecting a transmitter to one of the branch power lines L1 and L2 and a receiver to the other of the branch power lines, a communication signal is transmitted via the power line bridge 2a, and power line communication becomes possible. When performing power line communication between the branch power line L1 and the branch power line L4, the power line bridges 2a, 2
The communication signal is transmitted via b and 2c, and the branch power line L1
Power line communication can be performed between the branch power line L4 and the branch power line L4. Similarly, communication signals can be transmitted between the other branch power lines via the power line bridge, and power line communication can be performed.

FIG. 3 is a block diagram of the second embodiment of the present invention. The difference from the first embodiment described above is that one branch power line and another branch power line are connected by the power line bridge without connecting the power line bridges 2a to 2c in series. In this embodiment, the first
The branch power line L1 and the other branch power lines L2 to L4 are connected by power line bridges 2a, 2b and 2c, respectively. The same members as those in the first embodiment are designated by the same reference numerals. In the second embodiment, when the power line communication is performed between the transmitter and the receiver connected to the branch power line L1 and the other branch power lines L2 to L4, the power line bridges 2a to 2 are used.
via any one of b. In addition, branch power line L
When power line communication is performed between the transmitter and the receiver connected to the branch power lines L2 to L4 other than 1, the power line communication is performed via two power line bridges. For example, when performing power line communication between a transmitter and a receiver connected to the branch power line L2 and the branch power line L4, the power line bridge 2a and the power line bridge 2
Power line communication is performed via c.

Further, each branch power line may be connected by combining the first embodiment and the second embodiment. For example,
In FIG. 1, when a transmitter and a receiver are also connected to the branch power lines L5 and L6 to perform power line communication, the connection method as shown in FIG. 3 is used in addition to the connection of FIG. L4 and L5 and L4 and L6 may be connected by a power line bridge. Even with such a combination of connections, power line communication between the branch power lines L1 to L6 becomes possible.

FIG. 4 is a block diagram of the third embodiment of the present invention. In the above-described first and second embodiments, the breakers 4a to 4j are examples of double cutting (breakers that cut off both of the pair of power lines), but in this embodiment, the breakers are single-cut (of the pair of power lines. This is an example in the case of a breaker that disconnects only one of the power lines. Also in this embodiment, similar to the embodiment shown in FIG. 1, the trunk line L0 to the breaker 4k
The power line bridges 2a to 2c of the power line signal transmission device 2 are connected to the inner branch power lines L1 to L4 of the branch power lines L1 to L10 branched through 4 to 4t. That is,
The power line bridges 2a to 2c are connected in series, and the two ends of the series circuit of the power line bridges connected in series and the transmission lines connecting between the power line bridges are the breakers 4k to 4k, respectively.
It is connected to one of the branch power lines connected to 4n and the other of the branch power lines branched from the trunk line L0.

The operation of this embodiment is the same as that of the first embodiment shown in FIG. Further, even when the breaker is one-sided, each branch power line L1 to L4 may be connected by a power line bridge as shown in FIG. FIG. 5 is a perspective view of a power line signal transmission device 2 that accommodates a plurality of the power line bridges and is easily attached to a distribution board. The example shown in FIG. 5 is an example of the power line signal transmission device 2 in which two power line bridges are housed. Two power line bridges are housed in the housing 50, a pair of transmission lines of the two power line bridges are connected to each other and connected to the transmission lines, and a pair of connection lines 52 for connection with a branch power line is formed. It is led out of the housing 50. In addition, connection lines 51 and 53 for connecting to a branch power line are connected to the remaining transmission lines of the two power line bridges (transmission lines at both ends of a series circuit in which the two power line bridges are connected in series). Has been led to the outside of.

For example, referring to the example of FIG. 1, the power line bridges 2a and 2b are mounted inside the housing, the transmission lines J3 and J4 of the power line bridge 2a are connected to the transmission lines J1 and J2 of the power line bridge 2c, and A connection line 52 is connected to this connection transmission path and is led out to the outside of the housing. The transmission lines J1 and J2 of the power line bridge 2a are connected to the pair of connecting lines 51 and led out of the housing. Further, the transmission lines J3 and J4 of the power line bridge 2b are connected to a pair of connecting lines 53 and led out to the outside of the housing. When the example of FIG. 1 is applied, the connecting line 51 is the branch power line L.
1, the connection line 52 is connected to the branch power line L2, and the connection line 53 is connected to the branch power line L3. Since the power line signal transmission device 2 shown in FIG. 5 includes only two power line bridges, the power line bridge 2c in FIG. 1 is not provided.

Further, in the housing 50 of the power line signal transmission device 2, screw type connection terminals 54 are provided corresponding to the connection lines 51 to 53.
To 56 and independent connection terminals 57 are provided, and these connection terminals 54 to 57 are connected to each other by connecting wires 58 inside the housing 50.
It is electrically connected with. When the power line signal transmission device 2 is applied to a one-sided breaker as shown in FIG. 4, as shown in FIG.
One side of 3 is connected to each of the connection terminals 54 to 56, and the other side is connected to the line connected to the breaker of the branch power line.
Further, a new connection line 59 is connected to the independent connection terminal 57, and this connection line 59 is connected to the line of the trunk line L0 to which the breaker is not connected or the branch connection line to which the breaker is not connected. By connecting in this way, a connection circuit as shown in FIG. 4 can be obtained (however, since only two power line bridges are provided, for example, the circuit does not include the power line bridge 2c in FIG. 4).

In FIG. 5 and FIG. 6, reference numeral 50a indicates
The power line signal transmission device 2 is fixed to a distribution board by flange portions provided on both sides of a casing 50 of the power line signal transmission device, and the power line signal transmission device 2 is divided through holes provided in the flange portion. It is to be screwed to the electric board. 5 and 6
In the embodiment of the power line signal transmission device 2 shown in (1), the number of power line bridges is specified, and the number of branch power lines to be connected is limited. Therefore, FIG. 7 and FIG. 8 show an embodiment of the power line signal transmission device 2 which is composed of a plurality of connected single units so that any number of power lines can be connected. In this embodiment, FIG.
A combination of a first connection unit 60 having an outer shape shown in (a) which is a rectangular parallelepiped and a second connection unit 70 having an outer shape which is the same as that of the first connection unit shown in FIG. 7B. Composed of.

FIG. 7 (a ') is a diagram showing the circuit configuration of the first connection unit 60. Inside the housing 61 of the first connection unit 60, a power line bridge 62 having the configuration shown in FIG. 2 is provided. The receptacles R1 and R2 are connected to the pair of transmission lines on one side of the power line bridge, and the plugs P1 and P2 are connected to the pair of transmission lines on the other side of the power line bridge.
, P2 and the receptacles R1 and R2 are arranged at positions corresponding to one surface and the other surface of the housing 61 facing each other. Further, a third receptacle R3 and a third plug P3 are arranged on the surface on which the receptacles R1 and R2 are arranged and on the surface on which the plugs P1 and P2 are arranged, respectively, and the third receptacle and the third plug are mounted on the housing. Inside the body 61, they are connected by a conductive wire and are electrically connected. Then, the conductor is connected to a connection terminal 64 provided outside the housing 61, and the third receptacle, the third plug and the connection terminal 64 are electrically connected. In addition, a pair of connecting wires 63 are provided in the transmission line to which the receptacles R1 and R2 are connected.
Are respectively connected and led out of the housing 61.

The receptacle R in the housing 61
One surface sandwiched between the surface provided with 1, R2 and R3 and the surface provided with the plugs P1, P2 and P3 is a mounting surface for a distribution board or the like, and the first surface is provided at a corner on a diagonal line. The fixing claws 65 and 65 for fixing the connection unit are provided, and the other diagonal corners are formed with notches having a shape for fitting and accommodating the fixing claws 65 and 65. Fixing claw storage 6
6, 66 are provided. The connection terminal 64 is provided on the surface facing the attachment surface, and the connection wire 63 is provided from one surface constituting a side surface when the first connection unit 60 is attached to a distribution board or the like. It has been derived.

7 (b) and 7 (b ') show the second connection unit 7
0 is a perspective view and a circuit configuration diagram thereof. The housing 71 of the second connection unit 60 has the same shape as the first connection unit 60, and has a mounting surface on the distribution board, receptacles R1, R2, R.
The relationship between the surface on which 3 is provided, the surface on which the plugs P1, P2 and P3 are provided, the surface at which the connecting wire 73 is led out, the surface at which the connecting terminal is provided, etc. are the same as those of the first connecting unit 60, and the fixing tabs 65,
5. The fixing claw accommodating portions 66, 66 are also arranged in the same shape and at the same arrangement position, and are designated by the same reference numerals as those of the first connection unit 60. Furthermore, the receptacles R1, R2, R3,
The plugs P1, P2 and P3 are also arranged in the same positional relationship as the first connection unit 60. The external appearance of the second connection unit 70 is different from that of the first connection unit 60 in that the plug P1 is provided on the surface provided with the connection terminal 74 (the terminal corresponding to the connection terminal 64 of the first connection unit). , P2 is provided with a pair of terminals 75 electrically connected thereto.

As shown in FIG. 7 (b '), the electric circuit provided inside the housing 71 of the second connection unit has no power line bridge, and the receptacles R1 and R are not provided.
2 is connected to the pair of connecting wires 73, and is connected to the plugs P1 and P2.
Is connected to the pair of terminals 75. Further, the receptacle R3, the plug P3, and the connection terminal 74 are connected,
The point of being electrically connected is the first connection unit 60
Is the same as The first connection single body 60 and the second connection single body 70 are combined to form a power line signal transmission device, and the first connection single body 60 having the power line bridge 62 has the number of branch power lines to be connected ( It is necessary to prepare one less than the number of breakers), and to prepare at least one second connection single body 70 to configure the terminal portion of the power line signal transmission device. Furthermore, as described below,
Depending on the positional relationship of the branch power lines to be connected, when the second single connection unit is simply used as a connection unit between the single connection units, it is necessary to prepare the number of the connection units.

FIG. 8 shows a configuration in which two first connecting units 60 and two second connecting units are used for connecting three branch power lines branched by three single-sided breakers. It is a perspective view of the Example of the power line signal transmission device 2 which did. Plugs P1 to P3 of the first first connection unit 60-1
To the receptacle R1 of the first second connection unit 70-1.
While being inserted into R3, the fixing claw 65 and the fixing claw accommodating portion 66 of the first connecting single body 60-1 and the second connecting single body 70.
-1 fixing claw accommodating portion 66 and fixing claw 65 are fitted to each other to connect the first first connecting unit 60-1 and the second second connecting unit 60-1.
The connection unit 70-1 is joined. In addition, the plugs P1 to P3 of the first second connection unit 70-1 are inserted into the receptacles R1 to R3 of the second first connection unit 60-2, and the fixing claw 65 and the fixing claw accommodating portion. 66 are fitted together. Further, the plugs P1 to P3 of the second first connecting unit 60-2 and the receptacles R1 to R3 of the second second connecting unit 70-2 are fitted with the fixing claws 65 and the fixing claw accommodating portions 66, respectively. I am combining.

Then, one of the pair of connecting lines 63, 63, 73 of the first, second and first connection units 60-1, 60-2 and the second connection unit 70-2 is its own line. Connection terminal 6
4, 64, 74, and the other line is connected to the first branch power line L1, the second branch power line L2, and the third branch power line L2.
Wires to connect to the wires to which the breakers in 3 are connected, respectively. Further, one of the connection terminals 64, 64, 74, 74 (in FIG. 8, the connection terminal 74 of the second second connection unit 70-2) is connected to the breaker of any of the branch power lines via the lead wire 80. It should be connected to a line that is not connected or a line that is not connected to the breaker of the branch power line of the main line L0.

The pair of connection lines 73 of the first second connection unit 70-1 are connected to the corresponding terminals 75.
As a result, the receptacles R1 and R2 and the plugs P1 and P2 of the first second connection unit 70-1 are connected to each other. The reason why the first second connection unit 70-1 is provided is that the branch power line connecting one of the connection lines 63 of the first first connection unit 60-1 and the second first connection unit 60-1 are connected to each other. There is a distance from the branch power line that connects one of the connection lines 63 of the connection unit 60-2, and the first and second first
This is provided when it is not possible to connect the connection lines 63 of the individual connection units 60-1 and 60-2 to the corresponding branch power lines. If this distance is short and connection is possible, the first second connection unit 70-1 is not provided, and the plugs P1, P2, and P3 of the first first connection unit 60-1 are connected to the second first connection unit 60-1.
-2 receptacles R1, R2 and R3 may be directly inserted and connected.

The power line signal transmission device 2 coupled as described above
After the construction of the above, the connection board is connected to the distribution board with a fixing tool such as a tapping screw through the attachment holes provided in the fixing claws 65, 65 remaining at both ends of the power line signal transmission device 2 of the combination of the four connected single bodies. It is fixed and one of the pair of connecting lines 63 of the first first connecting unit 60-1 is connected to the line connected to the breaker of the first branch power line L1, and the second first connecting unit 60-1 is connected.
-2 is connected to one of the pair of connecting lines 63 connected to the breaker of the second branch power line L2, and one of the pair of connecting lines 73 of the second second connection unit 70-2 is connected to the third side. Connected to the line connected to the breaker of the branch power line L3 of
0 is connected to a line to which no breaker in any branch power line is connected or a line to the branch power line of the main line L0 which is not connected to a breaker. With the above configuration, the same configuration as in the case without the power line bridge 2c can be achieved in FIG. 4, and the branch power lines L1 to L
Power line communication between 3 becomes possible.

If the branch power line is connected to the main line L0 by a breaker with double cuts, it is not necessary to provide the conductor 80, and the first and second connection units 60 in FIG.
-1, 60-2 as a pair of connecting lines 63, 63 and the second connecting unit 70-2 as a pair of connecting lines 73 are branched power lines L1, L2.
, L3, the power line bridge 2 in FIG.
If there is no c, the circuit configuration becomes three branch power lines L1.
, L2, L3 enables power line communication. In the first and second connection units shown in FIGS. 7 and 8, the connection lines 63 and 74 are led out from the receptacles R1 and R2, but the connection lines 63 and 74 are connected to the plug side and led out. May be. In this case, the terminals 75 are the receptacles R1 and R2.
Will be connected to.

[0029]

EFFECTS OF THE INVENTION By using the power line signal transmission device of the present invention, power line communication is performed between branch power lines branched from a main line via a breaker in a closed area such as one store, one house, and one building. As a result, the power line communication system can be easily constructed, and the system construction cost can be reduced. Further, by configuring the power line signal transmission device of the present invention with a combination of the first and second connection units, the power line can be efficiently used with the minimum number of power line bridges regardless of the number and arrangement of the branch power lines that perform power line communication. A signal transmission device can be configured.

[Brief description of drawings]

FIG. 1 is a block diagram showing a circuit configuration of a first exemplary embodiment of the present invention.

FIG. 2 is a circuit configuration diagram of an embodiment of a power line bridge of the present invention.

FIG. 3 is a block diagram showing a circuit configuration of a second exemplary embodiment of the present invention.

FIG. 4 is a block diagram showing a circuit configuration when the breaker of the third exemplary embodiment of the present invention is a single-sided breaker.

FIG. 5 is a perspective view of an example of a power line signal transmission device of the present invention.

FIG. 6 is a diagram showing an example in which the power line signal transmission device shown in FIG. 5 is applied to a case where the breaker is a single-sided breaker.

FIG. 7 is an external perspective view of the first and second connection units of the present invention and a circuit configuration diagram thereof.

FIG. 8 is a diagram showing a usage pattern of the first and second connection units of the present invention.

[Explanation of symbols]

 1 power line signal transmission device 2 power line signal transmission device 3 main breakers 4a to 4t, 62 power line bridge L0 trunk line L1 to L10 branch power line 60 first connection unit 70 second connection unit R1 to R3 receptacle P1 to P3 plug

Claims (9)

[Claims] 1. A power line bridge composed of a circuit for removing a power supply frequency band and passing a certain band of a communication signal is connected between two sets of power lines of a pair of power lines branched from a main line via a breaker, A power line signal transmission device that enables power line communication between two sets of power lines. 2. A power line bridge having a pair of transmission lines, which is composed of a circuit that removes a power supply frequency band and passes a certain band of a communication signal, is connected to a power line in a distribution board to be communicated. The number of breakers provided is one less than that, the power line bridges are connected in series, and each pair of power lines branched from the trunk line via the breaker is connected to a pair of transmission lines between the power line bridges. A power line signal transmission device that enables power line communication between power lines by connecting the remaining power lines to a pair of transmission lines at both ends of a series circuit of a bridge. 3. A power line bridge having two pairs of transmission lines, which is composed of a circuit for removing a power supply frequency band and passing a certain band of a communication signal, is connected to a power line to be communicated in a distribution board. Provide one less than the number of breakers, connect one pair of transmission lines of each power line bridge to a pair of power lines branched from the main line via the breaker, and connect the other pair of transmission lines of each power line bridge to the main line. A power line signal transmission device that enables power line communication between power lines by connecting to each of a pair of other power lines branched from the power line via a breaker. 4. When the breaker is a single-sided cut, one of the two pairs of transmission lines of each of the power line braids is connected to the same conductor, and the conductor is connected to the power line without the breaker. The power line signal transmission device according to claim 2 or 3, which is connected. 5. The power line bridge is arranged in a housing having a pair of plugs, a pair of receptacles, and a pair of power line connecting portions, and one set of the two pairs of transmission lines is connected to the plug and the other set. Is connected to the receptacle, and the power line connecting portion includes a first connection unit connected to the plug or one of the sets of the receptacle, a pair of plugs, a pair of receptacles, and a pair of power line connecting portions. The power line connecting part is composed of a housing.
In accordance with the connection between the power line connecting portion and the plug or the receptacle in the first connection unit, the second connection unit connected to one set of the plug or the receptacle is combined in at least one or more units to connect the connection unit. The power line signal transmission device according to claim 1, wherein the plug and the receptacle are connected to each other. 6. The connection terminal connected to a plug or a receptacle that is not connected to the power line connection portion of the second connection unit, is provided on the outer surface of the housing of the second connection unit. Power line signal transmission device. 7. The first connection single body and the second connection single body are provided with a third plug together with a pair of plugs, and provided with a third receptacle together with a pair of receptacles. The third receptacle is electrically connected, and when the pair of plugs of one connection unit and the receptacle of the other connection unit are connected, the third plug and the third receptacle are also connected. The power line signal transmission device according to claim 5 or claim 6. 8. The power line signal transmission device according to claim 7, wherein connection terminals connected to the third plug and the third receptacle are provided on an outer surface of the housing. 9. The circuit according to claim 1, wherein the circuit for removing the power supply frequency band of the power line bridge and passing a certain band of a communication signal comprises a high pass filter or a capacitor and a photo coupler. Power line signal transmission device.