FI115876B - Low Voltage Communication System Transmitter with Remote Unit - Google Patents

Description

115876

LOW VOLTAGE COMMUNICATION SYSTEM TRANSMITTER

the remote unit

The invention is suitable for use in preventing a signal transmitted by a transmitter of a communication system performing low voltage network transmission to a low voltage network with low load impedance Zload values and high low voltage network equivalent impedance Zir values. By the method of the invention and the structure of the transmitter, the Uload signal transmitted by the transmitter can be made across the load impedance Zload on the voltage-10 bus to be large enough even from a device to be transmitted to a low voltage network bus. Without the invention, reliable operation under the above conditions would at times be impossible due to the transmission signal being too small.

Conventional solutions generally have two problems: 1) The transmission signal level drops sharply when the network impedance is very low.

2) In the case of a mains, e.g. 230 V 50 Hz between phase and zero rail (LN), a sufficiently large transmit signal Uload * is not received in the case of::: 20 because other consumables switch between phase and zero l *,: _. cause a very high load on the signal frequency, i.e. low load impedance Zload · It matters • '1 ·' · that the transmitting device has a long cable connection (cable equivalent impedance Ζψ is high on the signal frequency and high load) em.

* »'S * f *» 25 for phase and zero rails. According to the voltage distribution principle, the Uload is then small, or '.'. the situation is bad. Figure 1 illustrates the damping effect of a cable in a conventional rat-1: Zload = 1 ohm.

;: In the most advanced state of the art, the problem of 1) has already been solved by:. /. The output signal of the 30 transmitters at the output terminal of the device remains almost constant, i.e., the network impedance »», ·,; independent of it. However, it does not help in solving problem 2) because

«I

this is due to the series impedance Z \ v of the power network cable and the low load impedance 2 115876 between the Zload phase and zero rails in the power network. There is a surprisingly good solution to the problem in the present invention, which almost completely eliminates the Zw signal attenuation effect of the electrical impedance impedance.

Figure 2 illustrates the damping effect of a cable in the invention with a Zload of 1 µm.

In the transmission situation, it is crucial that, for example, the "bus signal" Uload "of the block center apartment block, which is the signal voltage between phase rail L and zero rail N in the block UL-n, is as high as possible.

The apparatus according to the invention is characterized in that the apparatus is divided into two or more parts, at least a first part, comprising signal generating and controlling means 3 and a second part TX / REMU, the second part TX / REMU including at least a switching unit 50 for connection to the mains, whereby the connection cable length Lw is less than 1 m.

The invention is based on the fact that a device operating in a low-voltage network is divided into two parts: Y, the first part of which preferably comprises signal generating and controlling devices, and the second part comprises a remote transmitter unit, which is later used as n, t; mowing TX / REMU. The transmitter remote unit TX / REMU is placed as close as possible to the phase and voltage bus of a 230 V, 50 Hz Y-j mains network, eg in a group center. The connection cable is kept to a minimum, eg Lw is less than 1 m Possibly '... · The TX / REMU remote transmitter unit can be mounted on a busbar, if permitted by regulations. The first part of the unit can be located far away from the remote unit, • ·: tens or hundreds of meters away. On the other hand, the first part can also be placed (I · Y '' even near the remote unit, even as a common unit with the remote unit.

The invention will be explained in more detail with reference to the accompanying drawings in which; ; Figure 1 shows the damping effect of a cable in a conventional solution when Zload ·; * is 1 ohm

Figure 2 illustrates the damping effect of a cable in the invention when Zload is 1 ohm 3 115876

Figure 3 illustrates a simple embodiment of the invention.

Figure 4 illustrates an effective embodiment of the invention.

Figure 1 illustrates a conventional structure for generating and adjusting a signal to be supplied to the mains in block 20,40,50 whose distance from phase and zero rails L, N is a distance Lw, e.g. 10 m. From block 20,40,50 the signal supply cables, e.g. Connected to phase and zero rails at a distance of 10 meters. Block 20 is a signal amplifier, block 40 is a low or band pass filter, and block 50 is a switching unit for connection to a power grid. Figure 1 also shows the attenuation due to the distance Lw to the transmitted signal even before coupling to the phase rail L.

Figure 2 shows signal generating and adjusting devices 3 according to the invention at a distance of Ls = 9 m from the phase and zero rails L, N and a separate connection unit TX / REMU with proximity to the phase and zero rails about 1 meter from said rails. The transmission signal attenuation is significantly reduced before the signal is connected to the mains when the cable length is only 1 meter. The voltage level of the signal to be transmitted is adjusted only from the TX / REMU unit. The TX / REMU unit has at least a block 50, but may also have blocks 20 and 40.

; ; Fig. 3a shows a connection according to the invention to a single-phase network in which: a second part of the device: V is located at or near the group center at a cable distance of 0.3-1 * * · · meters from the phase and zero rails L, N. «·»; ·. : Cable length 1 - 5 m from TX / REMU. The second solution shows the same solution "" '1, but the connection is made to a three-phase network.

• »*

• I

A

Fig. 4 shows an efficient solution with a TX / REMU unit at the block center voltage rails L1, N1 with blocks 20.40, 50, from a very small cable connection (0.3 to 1 m) from the end rail R11. The first part 3 of the device is::: at a distance of the cable Ls (e.g. 1 -40 m): The TX / REMU remote unit of the transmitter is controlled by a signal cable from the first part of the dual-drive device; The signal cable, Ls, can be tens of meters and even more than 100 meters in length, and has no effect on the size of the Uload of the 115876 4 "bus signal". See Figures 2 and 4.

The TX / REMU transmitter remote unit is located, for example, in a residential apartment right next to the group switchboard (fuses and phase and zero bus and switch) or in its own enclosure. It comes with an electric cable from the rails of the switchgear through a fuse and a signal cable from the first part of the device, which usually has the operating lights and switches on the device.

The TX / REMU remote unit of the transmitter includes, for example, a signal amplifier 20 (e.g., 95-125 kHz), a low pass or band pass filter 40, but in any case includes a switch unit 50 for connection to the mains. The TX / REMU remote unit can also include many other functional areas and functions. It may also include a power transformer and a voltage regulator.

The first part 3 of the device can, for example, be placed in a living room at the end of a signal cable, for example in the living room. Usually there are device lights and operating switches and other controls.

Figure 3 shows a simple embodiment of the invention and Figure 4 shows: Y: a more efficient embodiment of the invention.

_; The second part of the transmitter, the remote unit TX / REMU, must be mechanically as possible: 1 compact and of a suitable shape for use in a convenient '·' way, eg in the electrical main control panel of a residential apartment block or kWh meter unit.

:, Y There is often not much available space. The fiber optic cable to the phase and zero rails L, N must be as short as possible (eg Lw = less than 1 m). Installation Limitations • ·: Observe applicable laws and regulations.

!

Claims (5)

5, 115876 A transmitter for transmitting a communication signal to a low-voltage network, the apparatus comprising a signal generating and regulating means (3) for transmitting the signal and auxiliary equipment such as a signal amplifier (20) and an interface cable transmitter 50 Hz phase rail (L) and zero rail (N) as connection points, characterized in that the apparatus is divided into two or more parts, at least a first part comprising signal generating and adjusting devices (3) and a second part (TX / REMU), TX / REMU) includes at least a switching unit (50) for connecting to the mains and an interface cable for connecting said second part to a low-voltage network, wherein the interface cable has a length (Lw) of less than 1 m. Transmitter according to claim 1, characterized in that the first part (3) and the second part (TX / REMU) are located in the same balance unit. Transmitter according to Claim 1, characterized in that the second part (TX / REMU) is formed as a remote unit with respect to the first part (3) and the distance between them (LS) is more than 1 m. Transmitter according to claim 1, characterized in that the signal supply and the interface cable can be connected to 1-phase rails (L), (N) in an alternating or direct current network. Transmitter according to claim 1, characterized in that the signal cable connecting the signal inputs is connectable to 3-phase rails (L1, L2, L3), (N). 1 «*» 6 115876