EP2704103A1 - Utility meter and electric appliance - Google Patents

Abstract

The consumer meter mechanism (2) has an electronic circuit (4) for detecting operating hours of alternating current electric load integrated into electric consumer (6). The electronic circuit comprises detection unit for detecting the load current (iL) and load voltage (UL) of electric consumer. A determination unit is provided for determining the load power of observed load current and load voltage of electric consumer.

Description

The invention relates to a consumer meter with the features mentioned in the preamble of claim 1 and an electrical consumer with this consumer meter.

It is known to equip electrical consumers with a consumption meter, in order to be able to settle the billing use-related with a customer, for example, in a equipment rental company. In an electrical appliance for this purpose, an industry standard cut of, for example, 50x25 mm provided by an electromechanical consumption hours counter is housed. When connecting the electrical appliance to an AC power, for example, a small motor is set in rotation and drives a mechanical counter. The counter can be equipped with a reset function or often deliberately designed without such, so that no manipulation of the meter reading is possible. This allows a retailer leasing electrical appliances to make a cheaper offer to its customers than competitors charging only after handover. Furthermore, alternatively or additionally, an accounting for energy consumption can be offered by taking the accumulated operating hours (and minutes, and optionally seconds) with the performance of the device for determining the energy consumption by a manual multiplication calculation. This is appropriate, for example, where the power grid belongs to an operator and is made available to many users of devices without a power meter for individual detection is or may be, for example, in a campsite or in a rental workshop. The possibility of individual recording of the energy consumption per electric appliance offers the Traders also have the advantage of offering their customers more precisely calculated, energy-related offers. The disadvantage here, however, that the performance of the electrical appliance must always go into the bill with the maximum nominal value. Depending on the load, however, electrical appliances can also consume less power so that the customer effectively has to pay more than consumed.

Use of available individual electricity meters via an intermediate plug is eliminated because it must be ensured that no customer can manipulate the meter reading. The consumer counter must also be able to be put into operation automatically by the connection of the electrical appliance to an AC mains and be stopped when switched off.

In addition, it is necessary to be able to install the consumer counter preferably in the same existing standard sections of the electrical appliances in order to upgrade an existing electrical appliance park with little effort.

In order to realize an energy detection, there are very compact electronic means which can detect the load current and load voltage of the electrical consumer and from this a current power and from this a summed up energy consumption can be determined. These known means are so compact that they can be easily fitted into the standard cutouts. However, this fails due to the large dimensions of the power supplies, which are required to produce a DC voltage of 5 volts from an alternating current of, for example, in Europe single-phase 230 VAC / 50Hz.

Furthermore, it is of course desirable that the consumer meter even consumes as little energy for its operation, even to generate any additional environmental impact.

Against this background, the object of the present invention is to create a consumer meter for an AC electric consumer, which, in addition to recording the operating hours, enables an exact detection of the energy consumption per use case, thereby precluding a manipulation of detected consumption values. A further object of the invention is that the consumer counter can still have compact dimensions to be installed in existing standard cutouts for retrofitting of electrical consumers.

This object is achieved by a consumer counter with the features of claim 1. Further preferred embodiments of the invention will become apparent from the remaining features mentioned in the dependent claims and their combinations.

The consumer meter for detecting operating hours of an AC electrical consumer is integrated into the electrical consumer and an electronic circuit is provided for detecting operating hours, allowing a much more compact construction of the consumer meter.

The electronic circuit preferably additionally has means for detecting load current and load voltage of the electrical consumer. It is preferably provided a means for determining the consumer power from detected load current and load voltage of the electrical consumer. Furthermore, in the electronic circuit a Means for determining the energy consumption of the electrical consumer from determined consumer power and detected time available.

According to a further preferred embodiment, a means for detecting the AC mains frequency is incorporated in the consumer counter, wherein this frequency is used as the clock frequency for detecting operating hours in an electronic time counter.

The supply of the electronic circuit with a DC voltage is performed by means of a power supply connected to the AC power supply, wherein the power supply is integrated in the consumer meter. This makes it possible that the consumer counter is activated by commissioning the electrical consumer. Likewise, no additional cables need to be routed from an external power supply and an external power supply must be housed and handled anywhere.

The power supply is preferably designed as a Kondenstornetzteil, or in particular a switching power supply or a transformer power supply. In particular, in the case of using a capacitor power supply, a very practical compactness of the consumer counter can be achieved so that it can be accommodated in a standard cutout of an electrical consumer.

The consumer counter according to the invention according to one of the previously described embodiments, in particularly preferred embodiments, preferably a digital display, wherein the power supply, electronic circuit and digital display are preferably realized on two boards, which are spaced apart are. In this case, all the electronic switching elements between the two boards are arranged so that they do not protrude outward.

In a further preferred embodiment of the consumer counter according to the invention, the board gap is potted with a resin, more preferably after installation in a housing. As a result, the electronic elements are mainly protected against moisture and a chemically aggressive environment, but also mechanically held together and preserved against mechanical damage during installation or repair.

The distance between the two boards is further preferably predetermined by the largest component of the power supply or the electronic circuit, such as by the Vorwiderstandskondensator a capacitor power supply or by the transformer of a transformer power supply. In particular, in the case of using a capacitor power supply so very compact dimensions of the consumer meter can be achieved because the power required for the function of the electronic circuit is very low, resulting in a correspondingly relatively small size and capacity of the series resistor.

The dimensions of the consumer counter are smaller or correspond to an industrial compact standard insert, which may for example be preferably 50 x 25 mm in width and height. For certain applications, the available depth is also limited so that the sizing of the counter must also take this into account.

According to advantageous further embodiments, the digital display has a row for displaying the energy consumption in kWh and / or a line for displaying the operating hours, wherein the two displays are particularly preferably 8 digits. Optionally, it can thus be provided that only one of the two display values is displayed.

According to particularly advantageous further embodiments, the electronic circuit has electronic means for permanently storing the recorded display values for operating hours and energy consumption even after the power supply has been switched off and for displaying the display values again on the display after switching on the power supply. This ensures that the display values can not be manipulated externally. However, the electronic circuit may include an internal reset switch to set the counter readings to zero or to restart the circuit after an error.

The AC voltage required to operate the consumer meter and the electrical consumer preferably has a country specific value and is used in a single phase between a phase and neutral or between two phases. However, in other preferred embodiments of the present invention, a consumer may also be connected and driven in three-phase fashion with remaining two unmonitored phases. The typical country-specific AC voltages may be 120, 127, 220, 230, and 380 volts or similar, with the frequency of the AC voltage also having a country-specific value, particularly 50 Hz or 60 Hz. An application-specific and country-specific electronic circuit of the consumer meter takes into account these country-specific values, so that the use of the consumer meter according to the invention is made possible in all countries.

According to a further aspect of the invention, the objects according to the invention are achieved by an electrical consumer having a consumer meter integrated in it according to one of the preferred embodiments described above or combinations thereof.

It should be noted that the features listed individually in the present description are combined with each other in any technically meaningful manner and can show further embodiments of the invention. The description additionally characterizes and specifies the invention, in particular in connection with the figures.

Figur 1

ein Blockschaltbild einer bevorzugten Ausgestaltung eines erfindungsgemäßen Verbraucherzählwerks und Elektroverbrauchers, und

Figur 2

eine Seitenansicht einer bevorzugten Ausgestaltung des erfindungsgemäßen Verbraucherzählwerks in schematischer Darstellung.

The invention will be explained below in embodiments with reference to the accompanying drawings. Show it:

FIG. 1

a block diagram of a preferred embodiment of a consumer meter according to the invention and electrical consumers, and

FIG. 2

a side view of a preferred embodiment of the consumer meter according to the invention in a schematic representation.

FIG. 1 shows a block diagram of a preferred embodiment of the consumer meter 2 and electrical consumer 6 according to the invention.

The consumer counter 2 here has, for example, a minimum number of external terminals 12, 13 and 14 of three. To the Terminals N and L _in the AC voltage U _{w is} connected and an output L _out leads _out the phase L again, to which an electrical consumer 6 is connected in series and in turn is supplied with a neutral terminal N for its operation.

The consumer counter 2 has a power supply 3, which can be designed as a capacitor power supply. The capacitor power supply 3 is the state of the art for a small DC power both more economical and more compact and cheaper than other power supplies feasible. In the present example, it supplies a DC voltage U _DC of 5 volts, which is provided to the electronic circuit 4. However, it has no galvanic isolation as a capacitor power supply and must therefore be particularly well insulated against contact.

Alternatively, the power supply can also be designed as a compact transformer power supply or a switched-mode power supply.

The electronic circuit 4 forms the actual electronic consumer counter. It has in each case a means for detecting the load current i _L and the load voltage U _L. There are known electronic means that scan a voltage and convert it into digital signals. For detecting the alternating-current side load current i _L , a resistor or shunt R serially connected in the phase line L is provided, at which a voltage drop U _{i is} detected. From the detected voltage drop results in the currently flowing load current.

The two values of the load current i _L and the load voltage U _L determined in this way become further in the electronic circuit 4 currently detected apparent power by an electronically executed multiplication linked. Due to the detected phase shift between i _L and U _L , the active power P _w can be determined. This determined current power is added up with discrete periods of time to a recorded amount of energy consumed, for example.

The timer is preferably the AC line frequency f _N , which is obtained by a means for determining the clock frequency and the electronic circuit is provided at a low voltage level of, for example, 5 volts.

The same is thus obtained clock signal f _N is used in the electronic circuit 4 to the continuous list of operating hours, so that no additional electronic clock is needed for example in the form of a conventional quartz clock and thereby fewer components having the electronic circuit 4 to the desired compactness of the consumer counter 2 and a cost saving additionally contributes.

When processing the clock signal, the electronic circuit preferably takes into account a country-specific alternating current frequency of 50 Hz or 60 Hz and can be adjusted with a correction factor implemented by circuitry.

Finally, the values thus obtained are calculated for hours worked and hours fractions thereof and the energy consumption in kWh (kilowatt hours) and fractions thereof on a digital display 5 where they can be read.

The digital display has a sufficient number of display sites, for example of 8 digits, for the respective application. The fractions of the hours and kWh can preferably be displayed with a decimal place display and the digital display 5 can be designed, for example, in two lines.

In the simplest case, the values for operating hours and energy consumption displayed on the display 5 are set to zero by switching off the electronic circuit and would restart each time. Another embodiment preferably ensures that the last enumerated values are stored and displayed again after switching them on again so that no manipulation of these values is possible. The last option offers practical advantages, especially in the rental business of the electrical consumers.

It should also be mentioned that the illustrated consumer counter according to the invention, although intended primarily for single-phase consumers, can be expanded and used in a simple manner for three-phase three-phase loads as well. For this purpose, only the missing two phases need to be connected independently of the present consumer counter 2 to the three-phase load and in the electronic circuit 4, starting from a symmetrical phase loading a corresponding circuit-computerized correction of the detected energy consumption can be made.

FIG. 2 shows a side view of a preferred embodiment of the consumer counter 2 according to the invention in a schematic representation.

The electronic circuit 2 is realized on two spaced apart and parallel boards 8 and 10. In this case, the circuit of the power supply is realized on the one of the two boards 8, here preferably on the AC side. The second board 10 offers above all the digital display 5 and the belonging to her display electronic components space. The electronic components of the electronic circuit 4, in particular the electronic means for detecting the load current, the load voltage and the clock frequency can be arranged on one of the two boards or distributed on both boards 8 and 10. The two boards are preferably signal-electrically connected by means of conductors.

According to a particularly preferred embodiment, the largest component of the power supply 3, here for example a series resistor capacitor 9 of a capacitor power supply, the decisive criterion for the minimum achievable distance between the two boards 8 and 9 and thus the achievable compactness of the entire consumer counter. This capacitor is therefore chosen according to the invention specifically with regard to its dimensions in height and diameter. The remaining components may be resistors, IC's, Zener diode and other capacitors.

To the outside only need three ports 12, 13 and 14 to be led out of the consumer counter 2. Terminal 14 supplies, for example, the neutral conductor N and terminals 12 and 13 each input the phase L _in and the output of the same phase L _out after voltage and current detection.

In preferred further embodiments, the circuit arrangement of two boards 8 and 10, for example, with an epoxy resin 11 are cast to the electronic To protect components against environmental influences such as moisture and especially to thereby ensure an electrically safe safe handling and finger-safe operation of the electrical consumer 6 and the consumer counter 2. This is particularly important in view of the preferred capacitor power supply, since it does not separate galvanically. To further increase this effect, the circuitry may be enclosed in a housing (not shown) and then potted with resin.

LIST OF REFERENCE NUMBERS

1

Electric consumer device with consumer counter

2

Consumer reference work

3

power adapter

4

electronic circuit

5

digital display

6

Electrical consumers, AC electrical consumers

7

Resistance, shunt

8th

circuit board

9

Capacitor, Vorwiderstandskondensator

10

circuit board

11

epoxy resin

12, 13, 14

external connection

uw

AC voltage

U _DC

DC voltage

U _L

Load Voltage

Ui

voltage drop

R

Resistance, shunt

N

neutral

L

phase conductor

L _in

entrance

L _out

output

KWh

kilowatt hours

Hz

heart

Claims (14)

Consumer counter (2) for detecting operating hours of an AC electrical consumer (6), integrated in the electrical consumer, characterized in that for detecting operating hours an electronic circuit (4) is provided. Consumer counter (2) according to claim 1, characterized in that the electronic circuit (4) comprises means for detecting load current (i _L ) and load voltage (U _L ) of the electrical consumer (6). Consumer counter (2) according to claim 1 or 2, characterized in that a means for determining the consumer power from detected load current (i _L ) and load voltage (U _L ) of the electrical consumer (6) is provided. Consumer meter (2) according to claim 3, characterized in that a means for determining the energy consumption of the electrical consumer (6) from determined consumer power and detected time is provided. Consumer counter (2) according to one of the preceding claims, characterized in that a means for detecting the AC mains frequency (f) is provided, wherein these Frequency is used as a clock frequency for detecting operating hours in an electronic time counter. Consumer counter (2) according to one of the preceding claims, characterized in that the supply of the electronic circuit (4) with a DC voltage (U _DC ) by means of a to the AC mains (U _w ) connected power supply (3) is executed, wherein the power supply in the consumer counter is integrated. Consumer counter (2) according to claim 6, characterized in that the power supply (3) is designed as a Kondenstornetzteil, a switching power supply or a transformer power supply. Consumer counter (2) according to one of the preceding claims, characterized in that it has a preferably digital display (5), wherein the power supply (3), electronic circuit (4) and digital display (5) on two boards (8, 10 ), which are spaced from each other, wherein between the boards all electronic switching elements are arranged, and more preferably, the board gap with a resin (11), more preferably after installation in a housing, is shed. Consumer counter (2) according to claim 8, characterized in that the distance between the two boards (8, 10) is predetermined by the largest component, such as capacitor (9) of a capacitor power supply or transformer of a transformer power supply. Consumer counter (2) according to one of the preceding claims, characterized in that the dimensions of the consumer counter correspond to an industrial compact standard insert, preferably 50 x 25 mm in width and height. Consumer counter (2) according to one of the preceding claims 8 to 10, characterized in that the digital display (5) has a line for displaying the energy consumption in kWh and / or a line for displaying the operating hours in hours, the two displays preferably 8 -stellig are. Consumer counter (2) according to one of the preceding claims 8 to 11, characterized in that the electronic circuit (4) has electronic means to permanently store the detected operating hours and energy consumption readings, even after the power supply has been switched off, and after switching on the power supply Power back to the display (5). Consumer counter (2) according to one of the preceding claims, characterized in that the AC voltage (U _w ) has a country-specific value and is used in a single-phase between a phase (L _in ) and neutral (N) or between two phases, wherein the consumer (6) also three-phase may be connected and driven with the remaining two unmonitored phases, the typical AC voltages 120, 127, 220, 230 and 380 volts, and the frequency (f) of the AC voltage (U _w ) having a country specific value, in particular 50 or 60 Hz, and the electronic circuit takes into account these country-specific values. Electrical consumer (6) with a consumer counter (2) according to one of the preceding claims.

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