U.S. patent application number 13/568759 was filed with the patent office on 2013-08-08 for method and system for detection of standby status in linear and non-linear charges connected to the electricity mains and automatic disconnection thereof.
This patent application is currently assigned to GOOD FOR YOU GOOD FOR THE PLANET, S.L.. The applicant listed for this patent is Jes s BARTOLOME GARC A, Joan Gabriel BERGAS JANE, Antoni SUDRI ANDREU, Miquel TEIXIDO CASAS, Jose Angel ZABALEGUI LABARTA. Invention is credited to Jes s BARTOLOME GARC A, Joan Gabriel BERGAS JANE, Antoni SUDRI ANDREU, Miquel TEIXIDO CASAS, Jose Angel ZABALEGUI LABARTA.
Application Number | 20130200880 13/568759 |
Document ID | / |
Family ID | 40031432 |
Filed Date | 2013-08-08 |
United States Patent
Application |
20130200880 |
Kind Code |
A1 |
BARTOLOME GARC A; Jes s ; et
al. |
August 8, 2013 |
METHOD AND SYSTEM FOR DETECTION OF STANDBY STATUS IN LINEAR AND
NON-LINEAR CHARGES CONNECTED TO THE ELECTRICITY MAINS AND AUTOMATIC
DISCONNECTION THEREOF
Abstract
The method permits the detection of `standby` state` in linear
and non-linear loads connected to the power grid and their
automatic disconnection, and comprises at least the detection of
the normal operating state of at least one load by means of
detection, and obtaining the maximum value of the current in said
operating state for the determination of the `standby state` of the
at least one load.
Inventors: |
BARTOLOME GARC A; Jes s;
(Madrid, ES) ; ZABALEGUI LABARTA; Jose Angel;
(Madrid, ES) ; SUDRI ANDREU; Antoni; (Barcelona,
ES) ; BERGAS JANE; Joan Gabriel; (Barcelona, ES)
; TEIXIDO CASAS; Miquel; (Barcelona, ES) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BARTOLOME GARC A; Jes s
ZABALEGUI LABARTA; Jose Angel
SUDRI ANDREU; Antoni
BERGAS JANE; Joan Gabriel
TEIXIDO CASAS; Miquel |
Madrid
Madrid
Barcelona
Barcelona
Barcelona |
|
ES
ES
ES
ES
ES |
|
|
Assignee: |
GOOD FOR YOU GOOD FOR THE PLANET,
S.L.
Madrid
ES
|
Family ID: |
40031432 |
Appl. No.: |
13/568759 |
Filed: |
August 7, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12600680 |
Feb 4, 2010 |
8249757 |
|
|
PCT/ES2007/000291 |
May 18, 2007 |
|
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13568759 |
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Current U.S.
Class: |
324/113 ;
324/76.11 |
Current CPC
Class: |
H02J 9/007 20200101;
G01R 19/0038 20130101; H02J 9/005 20130101; Y02B 70/30 20130101;
Y04S 20/20 20130101; G06F 1/3209 20130101 |
Class at
Publication: |
324/113 ;
324/76.11 |
International
Class: |
G01R 19/00 20060101
G01R019/00 |
Claims
1.-22. (canceled)
23. A method of determining the maximum value of a current in at
least one load in a normal operating state, said method comprising:
i) obtaining a first current value in the at least one load; ii)
obtaining a later current value in the at least one load after a
pre-established interval of time I; iii) determining if the later
current value is greater than the first current value; iv) storing
the greater of the first current value and the later current value
in memory; and v) repeating stages i) to iv) a pre-determined
number N times.
24. The method of claim 23, wherein the pre-established interval of
time I is between 0.1 ms and 1 ms.
25. The method of claim 24, wherein the pre-established interval of
time I is 0.5 ms.
26. The method of claim 23, wherein the pre-determined number N is
between 20 and 200.
27. The method of claim 26, wherein the pre-determined number N is
40.
28. The method of claim 23, wherein stages i) to v) for obtaining
the maximum value of the current of a load in normal operating
state are repeated a number of times M and the average of all the
maximum current values obtained is determined.
29. The method of claim 28, wherein M is between 2 and 16.
30. The method of claim 29, wherein M is 8.
31. A method for the detection of `standby` state` in linear and
non-linear loads connected to the power grid, said method
comprising: a. obtaining a maximum start-up current value in each
at least one load; b. obtaining a maximum current value in each at
least one load at a specific moment; c. obtaining a maximum current
value in each at least one load in the normal operating state
according to claim 23; d. comparing the maximum current value
obtained in each at least one load at the specific moment and the
maximum value of the current in each at least one load in the
normal operating state; e. comparing the maximum current value
obtained in each at least one load at the specific moment and the
maximum start-up current value of each at least one load; and f.
establishing said `standby` state` when the maximum current value
obtained in each at least one load is less than a percentage P of
the maximum value of the current of each at least one load in the
normal operating state.
32. The method of claim 31, further comprising: determining whether
the maximum current value obtained at the specific moment in each
load is greater than the maximum current value in the normal
operating state stored in the memory; and replacing the maximum
current value for the normal operating state stored in the memory
with the maximum current value obtained at the specific moment when
the maximum current value for the specific moment is greater than
the maximum current value for the normal operating state.
33. The method of claim 31, further comprising: determining whether
the maximum current value obtained at the specific moment in each
load is less than the maximum current value in the normal operating
state stored in the memory and greater than a percentage P of the
maximum value of the current of each load in the normal operating
state; and determining that the load is in normal operating state
when the maximum current value for the specific moment is less than
the maximum current value for the normal operating state stored in
the memory and greater than the percentage P of the maximum value
of the current of each load in the normal operating state.
34. The method of claim 31, further comprising: determining whether
the maximum current value obtained at the specific moment in each
load is less than the maximum current value in the normal operating
state stored in the memory and less than a percentage P of the
maximum value of the current of each load in the normal operating
state; and determining that the load is in `standby` state when the
maximum current value for the specific moment in each load is less
than the maximum current value for the normal operating state and
less than the percentage P of the maximum value of the current of
each load in the normal operating state.
35. The method of claim 31, further comprising: determining whether
the maximum current value obtained at the specific moment in each
load is less than the maximum current value in the normal operating
state stored in the memory and less than a value U of the current
of each load in the normal operating state; and determining that
the load is disconnected when the maximum current value obtained at
the specific moment in each load is less than the maximum current
value in the normal operating state stored in the memory and less
than the value U of the current of each load in the normal
operating state.
36. The method of claim 32, further comprising: determining a first
value as the maximum start-up current value obtained minus a
hysteresis HS value; determining a second value as the maximum
start-up current value obtained plus the hysteresis HS value;
determining whether the maximum current value obtained at the
specific moment in each load is between the first value and the
second value; and determining that the load is in `standby` mode`
from the start-up or connection when the load obtained at the
specific moment is between the first value and the second
value.
37. The method of claim 31, wherein P is between 30% and 50%.
38. The method of claim 37, wherein P is 50%.
39. The method of claim 35, wherein U is approximately 100 mA.
40. The method of claim 36, wherein HS is approximately 100 mA.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is filed under the provisions of 35 U.S.C.
.sctn.120 and is a continuation of U.S. patent application Ser. No.
12/600,680, filed on Nov. 18, 2009 and entitled "METHOD AND SYSTEM
FOR DETECTION OF STANDBY STATUS IN LINEAR AND NON-LINEAR CHARGES
CONNECTED TO THE ELECTRICITY MAINS AND AUTOMATIC DISCONNECTION
THEREOF" in the name of Jes s BARTOLOME GARC A, which claims
priority to International Patent Application No. PCT/ES2007/000291,
filed May 18, 2007, both of which are incorporated herein by
reference in their entirety.
TECHNICAL FIELD OF THE INVENTION
[0002] The field of application of the invention is within the
industrial sector of electrical energy in general, and more
particularly in the field of reduction and saving of electrical
consumption in linear and non-linear loads connected to the power
grid which are in `standby` or energy saving situation. The method
and system of the invention are applicable in the industrial and
tertiary sector, and in particular in the domestic field.
BACKGROUND OF THE INVENTION
[0003] At present, a large quantity of electrical devices, such as
videos, televisions, monitors, printers, photocopiers, etc., have
an operating state mode known as waiting or `standby` mode. Said
state is similar for the user to a mode of disconnection of the
apparatus, but, in fact, this is not the case, since the apparatus
remains connected, consuming electrical energy.
[0004] Years ago, the disconnection of a piece of equipment
literally meant this, the total disconnection of said equipment,
and, therefore, that the consumption thereof was zero, or, in other
words, the electricity meter did not record any consumption.
Nowadays, however, the meters continue to record consumption, and
the reason for this, among others, is the consumption of appliances
in `standby` mode`.
[0005] Increasingly frequently, electrical appliances are designed
to be connected to electricity 24 hours a day, 7 days a week, and
part of the electrical consumption of those appliances occurs when
the apparatus is not really being used, but while the electrical
appliance is in `standby` mode`. In some products, such as printers
or photocopiers, the `sleep` or `standby` mode entails an important
saving. Even so, these appliances record the greatest consumption
levels in `standby` among office computer systems and other
electrical appliances.
[0006] It is precisely the fact that the appliances are connected
24 hours a day which cause that, although the consumption in
`standby` of an apparatus is relatively low with respect to its
consumption in normal or working mode, in absolute terms it is
practically equivalent to it, since the number of hours that it
consumes energy whilst it remains on `standby` is much higher.
[0007] Various recent studies state that between 5 and 13 percent
of electricity of domestic use consumed in developed countries may
be attributed to appliances on `standby`, and it is forecast that
this FIGURE will continue to increase due to the progressive
increase in electrical appliances, computers and other electrical
or electronic appliances, both in the home and in the office.
[0008] To avoid these consumptions arising from electrical
appliances or other equipment provided with this `standby`
operating mode, there are solutions that in one or another way
detect that the corresponding equipment is for a certain time in
operating mode and after said time automatically disconnects.
[0009] The disadvantages of this type of solutions are varied, but
the difficulty in the measurement or calculation of the power which
determines that a piece of equipment is in `standby` mode` is
especially notable, and consequently, the reliability and the
response in its operation, i.e. the non-disconnection or the undue
disconnection of the apparatus.
[0010] Other more imaginative solutions try to detect the presence
of a user which theoretically is using the apparatus. In the case
of solutions which whereby, for example a presence sensor, detect
the presence of a user, and which therefore serves as criteria to
determine when an appliance should be disconnected. As is evident,
these solutions have, among others, the problem of reliably
detecting when said user is present, since on many occasions,
prolonged periods with absence of movement by the user could be
interpreted as the absence thereof, and therefore, an erroneous
disconnection could be determined. In turn, this type of solution
also has the reverse problem, i.e. that the user is present in the
place where the appliances are found but is not using them, for
which reason, no type of energy saving is achieved.
[0011] A known method to detect that a piece of equipment has gone
into `standby` consists of calculating or measuring the current
power that it is consuming, and to make said measurement of the
power, it is necessary to differentiate between linear and
non-linear loads.
[0012] A linear load, such as, for example, a water heater, as it
is supplied by a sinusoidal voltage, will also consume a sinusoidal
current. In this type of loads, the power calculation is relatively
easy since it only depends on RMS values of voltage and current and
on the power factor. The calculation of the RMS value is very
simple since, as they are sinusoidal waves, the RMS value is the
peak value of the wave divided by the root of two.
[0013] A non-linear load, with a sinusoidal supply voltage, will
not consume a sinusoidal current but a distorted wave. In this case
the calculation of the power consumed by these loads is complex
since as they are not sinusoidal waves the power is not
proportional to the product of the RMS values of voltage and
current and the power factor. In this case, neither does the RMS
value of the wave correspond to the maximum value divided by the
root of two. Electronic equipment is typically non-linear loads
since they integrate power sources to convert the sinusoidal
voltage of 230Vrms of the grid in a DC voltage of values generally
lower than 24Vdc.
[0014] Since these detection solutions of the `standby` mode`
operate both with linear loads and non-linear loads, but especially
with the latter since it is the electronic equipment which
incorporates low consumption modes, the method of power calculation
cannot be based on the measurement of RMS values and the power
factor. A more sophisticated method of calculation based on the
average of the instantaneous value of the power throughout a
defined time period should be used:
P = 1 T .intg. v ( t ) i ( t ) t = 1 N k = 0 N v ( k ) i ( k )
##EQU00001##
[0015] This alternative `standby` detection therefore demands
instantaneous measurements of voltage and current as well as an
important calculation power.
[0016] Another problem associated to this detection method is that
it is necessary to define a power threshold value from which it is
considered that a piece of equipment has entered in standby mode.
The problem arises when we have to define this threshold value. On
the one hand, the `standby` consumption is quite different when we
consider different types of appliances, for example, a television
and a printer. On the other hand, furthermore, the `standby`
consumption is quite different within the same type of appliance
according to their age, manufacturer, etc.
[0017] To all the above, we have to add that the circuits devoted
to calculating power also have a residual consumption which in
cases is quite considerable, which directly clashes with the
objective for which they were created.
DESCRIPTION OF THE INVENTION
[0018] The objectives of the invention are achieved by a method in
accordance with claim 1, a system in accordance with claim 20 and
means of program coding in accordance with claim 22. The particular
embodiments of the method object of the invention are defined in
dependent claims 2 to 19, and of the system object of the invention
in dependent claim 21.
[0019] More particularly, in order to resolve the aforementioned
problem, the present invention provides, in a first aspect, a
method for the detection of `standby` state` in linear and
non-linear loads connected to the power grid and the automatic
disconnection thereof, which comprises the following stages: [0020]
a) Detection of the normal operating state of at least one load by
a means of detection, measuring the maximum value of the current in
said at least one load in said operating state, [0021] b) Detection
of entry into `standby` mode` of the at least one load by the means
of detection establishing said `standby` state` when the current
value measured in each load at that specific moment is less than a
percentage P of the maximum value of the current of each load in
normal operating state, [0022] c) Start of means of timing at a
determined time T for each load when it goes into `standby` mode`,
and [0023] d) Disconnection of the at least one load and of the
means of detection when value of time T is reached on the means of
timing without the at least one load having returned to normal
operating state.
[0024] The method is based on the fact that whether it is a linear
or non-linear load, the peak current consumed should undergo an
important variation. This method has clear advantages with respect
to the calculation method of the aforementioned power consumed: it
is only necessary to sense the current consumed by the load and the
calculation which is has to perform is minimum. These advantages
are translated in a saving in components, space of printed circuit
board and microprocessor price. Another advantages are that it is
not necessary to define a threshold value if the equipment is
capable of "learning" the value in normal operation and from this
to detect an important variation.
[0025] In a particular embodiment, stage a) of the detection method
of `standby` state`, i.e. that corresponding to the production of
the maximum value of the current in a load in normal operating
state also comprises the following stages: [0026] i) Obtainment of
a first current value in the load, [0027] ii) Obtainment of a later
current value in the load after a pre-established interval, [0028]
iii) Verification if the current value in the load is greater than
the previous value and in said case storage of the current value in
means of memory, [0029] iv) Repetition of stages i) to iii) a
determined number of times.
[0030] Advantageously, stages i) to iv) of the phase of production
of the maximum current value in normal operating state is repeated
a determined number of times and the average of all the means of
the maximum current values obtained is achieved.
[0031] In a particular embodiment, stage b) of detection of entry
in `standby` mode` of at least one load also comprises measuring of
the maximum start-up current value in each load, and measuring of
the maximum current value in each load at a specific moment, and
after that the following stages, [0032] v) Comparison of the
maximum current value measured in each load at a specific moment
and the maximum value of the current in each load in normal
operating state, and; comparison of the maximum current value
measured in each load at a specific moment and the maximum start-up
current value of each load, and [0033] vi) Establishment of said
`standby` state` when the maximum current value measured in each
load is less than a percentage P of the maximum value of the
current of each load in normal operating state.
[0034] Aforementioned stage v) is justified so that the method and
system of the invention can act in the three cases described
below.
[0035] It is detected that some loads, in general low power, do not
modify the peak current consumed if it is in `standby` at the time
of the connection. This behaviour causes that the method of the
invention does not disconnect said loads if said load or appliance
is not used, i.e. it is not started and turned off (ON-OFF
transition). Examples of this type of loads are satellite TV
decoders, games consoles, etc. . . . Said behaviour is different in
the case of computer screens, printers and other loads which,
although they were in `standby` operating mode at the time of
connection, always have an important variation in the maximum value
of the current.
[0036] When a load is supplied from the power grid: [0037] Some
loads start up in normal operating mode and after a time, in
general a few seconds at most, enter `standby` mode`. As an
example, we can cite a printer or a computer screen, which
initially starts up in normal mode and if it does not detect a PC
connected, it goes to `standby` mode`. [0038] Some loads start up
in `standby` mode` if they were in this state when they were
switched off (OFF mode). As examples we can cite: decoders, DVD and
video players, sound systems, games consoles and televisions.
[0039] Thus, on using the method and system of the invention, three
cases may arise: [0040] 1. that the load is of the first type, i.e.
it starts up in normal operating mode and enters `standby` mode`
after a few seconds, and therefore, it will produce a clear
variation in current peaks consumed, [0041] 2. that there is no
load connected and, therefore, no variations occur in the reading
of the maximum or peak current, the load current being under a
determined value(load not unconnected), or [0042] 3. that there is
a load connected of the second type, i.e. with start-up in
`standby` mode` if when switched off they were is said state, so
that variations do not occur in the peak current reading, but in
this case it is above the determined value of `load not
connected`.
[0043] As has been indicated, said stage v) permits that the method
and system of the invention can act in the three mentioned
cases.
[0044] On the other hand, said stage v) of comparison, within stage
b) of detection of entry in `standby` mode`, permits contemplating
five possible scenarios.
[0045] In first place, the method for the detection of `standby`
state` establishes that, when the maximum current value measured at
a specific moment in each load is greater than the maximum current
value in the normal operating mode stored previously in the means
of memory, the maximum current value measured at that specific
moment replaces and is stored instead of that previous stored in
the means of memory.
[0046] In the same way, the method establishes that, when the
maximum current value measured at a specific moment in each load is
less than the maximum current value in normal operating mode stored
in the means of memory and greater than the determined percentage
of the maximum current value of each load in the normal operating
state, it is considered that the load is within the normal
operating state.
[0047] On the other hand, the method establishes that, when the
maximum current value measured at a specific moment in each load is
less than the maximum current value in normal operating mode stored
in the means of memory and below the determined percentage of the
maximum value of the current of each load in the normal operating
state, the load is considered in `standby` state.
[0048] The method for the detection of `standby` state` also
establishes that, when the maximum current value measured at a
specific moment in each load is less than the maximum current value
in normal operating mode stored in the means of memory and less
than a specific value (reduced) of the current of each load in
normal operating state, it is considered that the load is
disconnected, or, in other words, there is no appliance or load
connected to the system.
[0049] This condition obeys the need to not take into consideration
the electric "noise" that any electrical appliance always has, and
which logically does not correspond to a real consumption value in
`standby` mode`.
[0050] Finally, the method for the detection of `standby` state`
establishes that, when the maximum current value measured at a
specific moment in the load is between the two following values:
Maximum current value in Start-up minus an HS value, and, Maximum
current value in Start-up plus the HS value, it is considered that
the appliance or load is in `standby` mode` from when it was
started. The HS value corresponds to a hysteresis which is entered
to avoid that small noises in the measurement do not permit the
action of the `standby` detection system.
[0051] In a second aspect, the invention relates to a system for
the detection of `standby` state` in linear and non-linear loads
connected to the power grid and the disconnection thereof, which
comprises: [0052] a) Means of detection of the normal operating
state of the at least one load obtaining the maximum value of the
current in said operating state, [0053] b) Means of detection of
entry in `standby` mode` of the at least one load establishing said
`standby` state` when the existing value of current obtained in
each load is less than a percentage P of the maximum value of the
current of each load in normal operating state, [0054] c) Means of
timing at a determined time T for the at least one load when it
enters in `standby` mode`, and [0055] d) Means of disconnection of
the at least one load and of the means of detection when the value
T of the means of timing is reached without the at least one load
having returned to normal operating state.
[0056] In a particular embodiment, the system for the detection of
`standby` state` also comprises means of reactivation of the
system, which after `switching off` or disconnection thereof when
all the loads have gone into `standby` operating mode during the
determined time and established for that purpose, permit the
reactivation or resetting of the system, i.e. the re-start up to be
able to detect the `standby` mode`.
[0057] In a last aspect, the invention relates to means of program
coding adapted to execute one or several stages of the detection
method in the described `standby` mode.
[0058] In short, it can be concluded that the `standby` detection
method mode` of the invention has a series of advantages which
redound in a simplification of the method, less cost, both of the
sensing elements and the associated microprocessor, and in
particular, for an embodiment with mechanical reactivation means,
the zero consumption of the detection device when this disconnects
all the loads. In turn, the detection method by variation of the
current peak consumed in the load or loads has the advantage that
it is 100% automatic and it is only necessary to detect important
current variations and that, therefore, it is not necessary to have
great precision or a large calculation power.
BRIEF DESCRIPTION OF THE DRAWING
[0059] To complement the description being made, and in order to
help towards a better understanding of the characteristics of the
invention, in accordance with a preferred and practical embodiment
thereof, a single FIGURE is attached as an integral part of said
description, wherein with an illustrative and non-limitative
character, a flow chart has been represented which implements the
`standby` detection method of the present invention.
DESCRIPTION OF A PREFERRED EMBODIMENT
[0060] Below, a preferred embodiment of the `standby` detection
method of the invention is described by means of a functional
diagram represented in FIG. 1.
[0061] The method starts with two main parts a) and b). During the
first part a) (stages i) to iv)) the maximum current value is
sought, and it is stored as start-up peak value; then, the second
part b) (stages v) to vi)) of the method start, where this
"supervises" if the appliance or load enters in `standby` mode. To
do this, the maximum current value measured is sought and it is
compared with the maximum value in normal operating state and with
the maximum start-up current value.
[0062] More particularly, the first part of method a), comprises
the following stages: [0063] Stage i): Obtainment of a first
current value in the load, [0064] Stage ii): Obtainment of a later
current value in the load after a pre-established interval I [0065]
Stage iii): Verification if the existing value in the load is
greater than the previous value and in said case storage of the
existing value in means of memory, [0066] Stage iv) Repetition of
stages i) to iii) a determined number N of times. [0067]
Preferably, the value of interval I is between 0.1 ms and 1 ms, and
particularly, the interval I is 0.5 ms.
[0068] On the other hand, preferably, the value of the number of
times N that stages 1 to 3 is repeated is between 20 and 200, and
particularly N is 40.
[0069] To obtain a more precise maximum value, part a) of the
method is repeated a number of times M and then the average is
calculated. Preferably, the number of times M that part a) of the
method is repeated is between 2 and 16, and particularly M is
8.
[0070] Part b) of the method, i.e. that relative to the
"supervision" of whether the appliance or load enters in `standby`
mode comprises measuring of the maximum start-up current value in
each load, and measuring of the maximum current value in each load
at a specific moment, and after that the following stages, [0071]
Stage v): Comparison of the maximum current value measured in each
load at a specific moment and the maximum value of the current in
each load in normal operating state, and; comparison of the maximum
current value measured in each load at a specific moment and the
maximum start-up current value of each load, and [0072] Stage vi):
Establishment of said `standby` state` when the maximum current
value measured in each load is less than a percentage P of the
maximum value of the current of each load in normal operating
state.
[0073] The comparison made in stage v) of part b) of the method
poses five possible scenarios: [0074] That the maximum current
value measured at a specific moment in each load is greater than
that stored in the means of memory. This means that the maximum
normal operating current value which has been read is not correct,
and the current value measured at that moment is stored as normal
operating value. In other words, the method and the system "learn"
the new normal operating value. [0075] That the maximum current
value measured at a specific time in each load is less than that
stored in the means of memory but is more than a percentage P of
the maximum value of the current of each load in normal operating
state. It is considered, in this case, that that the appliance or
load is in normal operating mode. [0076] That the maximum current
value measured at a specific time in each load is less than that
stored in the means of memory and is less than percentage P of the
maximum value of the current of each load in normal operating
state. In this case it is considered that the appliance or load has
gone into `standby` operating mode. [0077] That the maximum current
value measured at a specific time in each load is less than a
threshold U of the current of each load in normal operating state.
In this situation it is considered that there is no appliance or
load connected to the system, [0078] That the maximum current value
measured at a specific time in each load is between the two
following values: Maximum Start-up current value minus an HS value,
and Maximum Start-up current value plus the HS value. It is
considered that the appliance or load is in `standby` mode` from
when it is started. The value of HS corresponds to a hysteresis
which is introduced to avoid that small noises in the measurement
do not permit the action of a standby detector system.
[0079] Preferably, the value of P is between 30% and 50%, and
particularly P is 50%. On the other hand, both the preferred value
of U and that of HS is approximately 100 mA.
[0080] Subsequently, in the cases where it is considered that the
load is in `standby` mode or in `not connected` mode, a timer T is
started for each load.
[0081] Finally, the load and the means of detection are
disconnected when value T of the timer is reached without the load
having returned to normal operating state. One of the main
advantages of the method and system of the invention is again
underlined, i.e. the zero consumption of the system when the load
is disconnected, as the means of detection are also disconnected.
In said situation, the system reset is carried out by mechanical
reactivation means, such as, for example the pushing of a button
provided for said purpose.
[0082] When a load wherein `standby` has been detected, and
consequently the timer T had been started, goes on to normal
operating state, the timer is reset.
* * * * *