U.S. patent application number 14/484656 was filed with the patent office on 2016-03-17 for triac low voltage dimming control system.
This patent application is currently assigned to Inspired LED, LLC. The applicant listed for this patent is Inspired LED, LLC. Invention is credited to Tanner J. Leland, James J. Levante, Randy J. Wright.
Application Number | 20160081146 14/484656 |
Document ID | / |
Family ID | 55450326 |
Filed Date | 2016-03-17 |
United States Patent
Application |
20160081146 |
Kind Code |
A1 |
Leland; Tanner J. ; et
al. |
March 17, 2016 |
TRIAC Low Voltage Dimming Control System
Abstract
A TRIAC low voltage dimming control system for effectively
controlling the dimming of low voltage lighting using a TRIAC
dimmer. The TRIAC low voltage dimming control system generally
includes a TRIAC analyzer that applies a test voltage to a TRIAC
dimmer and measures the amount of time required for the TRIAC
dimmer to conduct electricity. Utilizing the measured time for the
TRIAC dimmer to conduct electricity, the TRIAC analyzer is able to
calculate an approximate state of the TRIAC dimmer and provide a
corresponding level of DC electrical power to a DC load.
Inventors: |
Leland; Tanner J.; (Tempe,
AZ) ; Levante; James J.; (Tempe, AZ) ; Wright;
Randy J.; (Chandler, AZ) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Inspired LED, LLC |
Tempe |
AZ |
US |
|
|
Assignee: |
Inspired LED, LLC
|
Family ID: |
55450326 |
Appl. No.: |
14/484656 |
Filed: |
September 12, 2014 |
Current U.S.
Class: |
315/250 ;
315/287 |
Current CPC
Class: |
G01R 19/0084 20130101;
H05B 39/08 20130101; H05B 45/37 20200101; H05B 45/50 20200101; H05B
45/10 20200101 |
International
Class: |
H05B 33/08 20060101
H05B033/08 |
Claims
1. A light dimming control system for low voltage lighting,
comprising: an analyzer adapted to apply a test voltage to a TRIAC
dimmer and to measure a period of time required for said TRIAC
dimmer to start conducting electricity after applying said test
voltage, wherein said analyzer calculates a state of said TRIAC
dimmer based upon said period of time, and wherein said test
voltage is comprised of a direct current (DC) voltage; a low
voltage dimmer in communication with said analyzer, wherein said
analyzer transmits a signal to said low voltage dimmer specifying a
DC output voltage for said low voltage dimmer; and a low voltage
lighting electrically connected to said low voltage dimmer, wherein
said low voltage lighting receives said DC output voltage.
2. The light dimming control system of claim 1, wherein said test
voltage is greater than 30V DC.
3. The light dimming control system of claim 2, wherein said test
voltage is at least 48V DC.
4. The light dimming control system of claim 2, wherein said test
voltage is approximately 48V DC.
5. The light dimming control system of claim 1, wherein said
analyzer removes said test voltage from said TRIAC dimmer after
said TRIAC dimmer starts to conduct electricity.
6. The light dimming control system of claim 1, wherein said
analyzer removes said test voltage from said TRIAC dimmer for a
discharge time after said TRIAC dimmer starts to conduct
electricity.
7. The light dimming control system of claim 6, wherein said
discharge time is at least an amount of time sufficient to allow a
capacitor in said TRIAC dimmer to discharge.
8. The light dimming control system of claim 6, wherein said
analyzer again applies said test voltage after said discharge
time.
9. The light dimming control system of claim 6, wherein said
discharge time is at least 50 milliseconds.
10. The light dimming control system of claim 1, wherein said
analyzer determines that said TRIAC dimmer is conducting
electricity when said TRIAC dimmer conducts a minimum electric
current when said test voltage is applied.
11. The light dimming control system of claim 10, wherein said
minimum electric current is comprised of at least 50 milliamps
(mA).
12. The light dimming control system of claim 1, wherein said low
voltage lighting is comprised of at least one light emitting diode
(LED).
13. The light dimming control system of claim 12, wherein said low
voltage lighting is comprised of an LED light strip.
14. The light dimming control system of claim 1, wherein said TRIAC
dimmer is comprised of a first main terminal, a second main
terminal and a ground terminal, wherein said analyzer is
electrically connected to said first main terminal and said second
main terminal of said TRIAC dimmer.
15. The light dimming control system of claim 14, wherein said
ground terminal of said TRIAC dimmer is not electrically connected
to anything.
16. The light dimming control system of claim 1, wherein said state
of said TRIAC dimmer calculated by said analyzer is comprised of an
estimated dimming position for a dimming switch of said TRIAC
dimmer, wherein said estimated dimming position is calculated by
said analyzer based upon said period of time.
17. The light dimming control system of claim 16, wherein said DC
output voltage of said low voltage dimmer is inversely proportional
to said period of time.
18. The light dimming control system of claim 1, wherein said
analyzer is in wireless communication with said low voltage
dimmer.
19. The light dimming control system of claim 1, wherein said
analyzer is in wired communication with said low voltage
dimmer.
20. A method of dimming DC voltage lighting based upon a state of a
TRIAC dimmer, comprising the steps of: providing a control unit
comprised of an analyzer and a low voltage dimmer, wherein said low
voltage dimmer is adapted to electrically connect to a low voltage
lighting and provide a DC output voltage to said low voltage
lighting at different levels to dim said low voltage lighting;
applying a test voltage to a first main terminal and a second main
terminal of a TRIAC dimmer, wherein said test voltage is comprised
of a DC voltage of at least 30V DC; determining a period of time
for said TRIAC dimmer to conduct a minimum electric current;
calculating an illumination level that is inversely proportional to
said period of time; and applying said DC output voltage at a level
that corresponds to said illumination level.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] Not applicable to this application.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable to this application.
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The present invention relates generally to a low voltage
dimmer and more specifically it relates to a TRIAC low voltage
dimming control system for effectively controlling the dimming of
low voltage lighting using a TRIAC dimmer.
[0005] 2. Description of the Related Art
[0006] Any discussion of the related art throughout the
specification should in no way be considered as an admission that
such related art is widely known or forms part of common general
knowledge in the field.
[0007] Low voltage lighting has become increasingly popular in
various applications such as but not limited to light-emitting
diode (LED) based lighting, under cabinet lighting, TV back
lighting, staircase lighting, architectural lighting, bar lighting,
kitchen lighting, toe kick lighting, ceiling cove lighting, ceiling
can lighting, troffer lighting, decorations, landscape lighting and
vehicles. Most low voltage lighting utilizes low-voltage direct
current (DC) electrical power that is less than 120V DC such as 12V
DC, 24V DC or 48V DC.
[0008] LED based lighting has become an increasingly popular type
of low voltage lighting because of the low power, low heat and
color changing characteristics of LED lights. Examples of LED based
lighting include LED light fixtures, LED light bulbs, LED light
strips, flexible LED light strips, outdoor LED lighting, LED
landscape lighting, recessed LED lighting, LED security lighting
and LED flat panel lights. To illustrate one type of LED based
lighting, a flexible LED light strip is comprised of an elongated
flexible strip of printed circuit board (PCB) having two or more
electrically conductive traces to provide electrical power, a
plurality of light-emitting diodes attached along the front surface
of the flexible strip and electrically connected to the conductive
traces, and a length of adhesive along the back surface of the
flexible strip.
[0009] Low voltage power supplies are used to convert high voltage
alternating current (AC) electrical power (e.g. 120V AC, 240V AC)
to low voltage direct current (DC) electrical power (e.g. 12V DC,
24V DC, 48V DC) to provide low voltage DC electrical power to
various electrical devices such as low voltage lighting including
LED lighting. Low voltage power supplies are often times referred
to as "AC/DC power supplies", "switch-mode power supplies" or
"magnetic low-voltage transformers". Low voltage power supplies are
typically comprised of a magnetic transformer electrically
connected in series with a rectifier to create a single-phase
rectifier circuit that converts 120V AC to a low voltage (e.g. 12V
DC). U.S. Pat. No. 3,353,083 (Greenberg) discloses an exemplary
AC/DC power supply using a magnetic transformer and rectifier in
series to convert AC electrical power to DC electrical power. Low
voltage power supplies are used to provide electrical power to
various types of low voltage lighting.
[0010] There are two main types of low voltage dimmers used to
control light emitted from LED based lighting: Pulse-width
modulation (PWM) LED dimmers and analog LED dimmers. PWM LED
dimmers control the duty cycle of the low voltage power supplied to
the LED based lighting thereby adjusting the luminosity of the LED
lights. Analog LED dimmers provide variable current to the LED
based lighting either through limiting the current or adjusting the
applied voltage thereby changing the luminosity of the LED
lights.
[0011] Conventional AC based light dimmers such as TRIAC (triode
for alternating current) dimmers (a.k.a. TRIAC dimmer switches) are
commonly utilized to dim AC high voltage lighting (e.g.
incandescent or halogen lighting) which typically operate at 120V
AC. TRIAC dimmers typically have a sliding dimmer switch (a.k.a.
"slide dimmer"), rotating knob switch (a.k.a. "rotary dimmer") or a
plurality of buttons to select a desired dimming level for lights.
TRIAC dimmers may also have a power switch to allow for turning off
or on the electrical power from the TRIAC dimmer regardless of the
position of the dimmer control switch. TRIAC dimmers are widely
available in stores and come in various colors, designs and
configurations thereby allowing consumers to select from a wide
variety of dimmer switch options.
[0012] Because a conventional TRIAC dimmer is designed to be only
used with a pure resistive load (e.g. incandescent light bulb or
halogen bulb), TRIAC dimmers are not suitable for use in
combination with low voltage power supplies which are an inductive
load. Hence, manufacturers and end users have been forced to
utilize dimmers that are specifically designed for low voltage
lighting.
[0013] Because of the inherent problems with the related art, there
is a need for a new and improved TRIAC low voltage dimming control
system for effectively controlling the dimming of low voltage
lighting using a TRIAC dimmer.
BRIEF SUMMARY OF THE INVENTION
[0014] The invention generally relates to a low voltage dimmer
which includes a TRIAC analyzer that applies a test voltage to a
TRIAC dimmer and measures the amount of time required for the TRIAC
dimmer to conduct electricity. Utilizing the measured time for the
TRIAC dimmer to conduct electricity, the TRIAC analyzer is able to
calculate an approximate state of the TRIAC dimmer and provide a
corresponding level of DC electrical power to a DC load.
[0015] There has thus been outlined, rather broadly, some of the
features of the invention in order that the detailed description
thereof may be better understood, and in order that the present
contribution to the art may be better appreciated. There are
additional features of the invention that will be described
hereinafter and that will form the subject matter of the claims
appended hereto. In this respect, before explaining at least one
embodiment of the invention in detail, it is to be understood that
the invention is not limited in its application to the details of
construction or to the arrangements of the components set forth in
the following description or illustrated in the drawings. The
invention is capable of other embodiments and of being practiced
and carried out in various ways. Also, it is to be understood that
the phraseology and terminology employed herein are for the purpose
of the description and should not be regarded as limiting.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Various other objects, features and attendant advantages of
the present invention will become fully appreciated as the same
becomes better understood when considered in conjunction with the
accompanying drawings, in which like reference characters designate
the same or similar parts throughout the several views, and
wherein:
[0017] FIG. 1 is a block diagram illustrating the control unit in
communication with a TRIAC dimmer to control low voltage
lighting.
[0018] FIG. 2 is a block diagram illustrating the control unit
comprised of a TRIAC analyzer and a low voltage dimmer.
[0019] FIG. 3 is a block diagram illustrating a 48V DC test voltage
applied to the TRIAC dimmer in a first polarity.
[0020] FIG. 4 is a block diagram illustrating a 48V DC test voltage
applied to the TRIAC dimmer in a second polarity that is opposite
of the first polarity.
[0021] FIG. 5 is a flowchart illustrating the overall functionality
of the TRIAC analyzer.
[0022] FIG. 6 is a chart illustrating an example of the test
voltage applied to the TRIAC dimmer.
[0023] FIG. 7 is a diagram illustrating the present invention
embodied directly and integrally formed within a housing of a low
voltage power supply.
[0024] FIG. 8 is a rear upper perspective view of an exemplary
housing for the low voltage power supply.
[0025] FIG. 9 is a block diagram illustrating the present invention
embodied directly and integrally formed within the housing of low
voltage lighting.
[0026] FIG. 10 is a chart illustrating the amount of time required
for an exemplary TRIAC dimmer comprised of a LEVITON.RTM.
SURESLIDE.RTM. 6672 to conduct current based upon the relative
slide position (0% to 100%) of the TRIAC dimmer when 48V DC is
applied to the TRIAC dimmer.
[0027] FIG. 11 is a schematic diagram of a basic TRIAC dimmer
circuit.
[0028] FIG. 12 is a schematic diagram illustrating a circuit used
by the microcontroller in the TRIAC analyzer to determine the state
of the TRIAC dimmer.
DETAILED DESCRIPTION OF THE INVENTION
A. Overview
[0029] Turning now descriptively to the drawings, in which similar
reference characters denote similar elements throughout the several
views, FIGS. 1 through 10 and 12 illustrate an electrical power
control system to control DC electrical power provided to a DC load
based upon a state (e.g. on or off, the brightness position) of a
TRIAC dimmer 50. The DC based load may be comprised of various DC
electrical devices such as but not limited to low voltage lighting
40, DC electrical motors and anything else that is powered by DC
electrical power.
[0030] FIGS. 1 through 10 and 12 further illustrate a TRIAC low
voltage dimming control system 10, which comprises a TRIAC analyzer
32 that applies a test voltage to a TRIAC dimmer 50 and measures
the amount of time required for the TRIAC dimmer 50 to conduct
electricity. Utilizing the measured time for the TRIAC dimmer 50 to
conduct electricity, the TRIAC analyzer 32 is able to calculate an
approximate state of the TRIAC dimmer 50 and provide a
corresponding level of DC electrical power to a DC load.
B. Low Voltage Power Supply
[0031] The low voltage power supply 20 may be comprised of any
power supply that converts high voltage AC electrical power (e.g.
120V AC) from an AC power supply 12 to low voltage DC electrical
power (e.g. 12V DC, 24V DC, 48V DC, etc.). The low voltage DC
electrical power provided by the low voltage power supply 20 is
less than 120V DC. The AC electrical power is provided via a
conventional AC power supply 12 such as an electrical wall outlet
or directly wiring into the power system of a building. U.S. Pat.
No. 3,353,083 (Greenberg) discloses an exemplary AC/DC power supply
using a magnetic transformer and rectifier in series to convert AC
electrical power to DC electrical power and is hereby incorporated
by reference herein to provide an exemplary low voltage power
supply 20 suitable for use in the present invention.
C. Low Voltage Lighting
[0032] The low voltage lighting 40 is comprised of any type of
lighting that is electrically powered by low voltage DC electrical
power that is less than 120V DC (e.g. 12V DC, 24V DC, 48V DC,
etc.). The low voltage lighting 40 used in the present invention is
preferably comprised of a light-emitting diode (LED) based lighting
such as, but not limited to, an LED, LED light fixtures, LED light
bulbs, LED light strips, flexible LED light strips, outdoor LED
lighting, LED landscape lighting, recessed LED lighting, LED
security lighting and LED flat panel lights.
[0033] As shown in FIGS. 1 and 2 of the drawings, the low voltage
lighting 40 is electrically connected to the low voltage dimmer 34
wherein the low voltage dimmer 34 provides adjustable DC electrical
power via a DC output voltage to the low voltage lighting 40 to
adjust the level and amount of light emitted by the low voltage
lighting 40.
D. TRIAC Dimmer
[0034] The TRIAC dimmer 50 is comprised of a conventional TRIAC
dimmer 50 switch that is in the thyristor family that is able to
conduct electricity in both directions such as in AC applications
(e.g. 120V AC applications). The TRIAC dimmer 50 is preferably
comprised of a wall mounted dimmer switch but may be comprised of
non-wall mounted dimmer switches.
[0035] A conventional TRIAC dimmer 50 is typically utilized to
control the luminosity of AC lighting (e.g. incandescent or halogen
lighting). The term "TRIAC" is often times referred to as "triode
for alternating current". The TRIAC dimmer 50 may be comprised of
various types of conventional TRIAC dimmers 50 such as slide
dimmers, rotatory dimmers and button controlled dimmers. The TRIAC
dimmer 50 may also include a power switch that turns on or off the
electrical power in addition to the adjustable control switch that
controls the level of electrical power to the lights. FIGS. 7 and 8
illustrate an exemplary TRIAC dimmer 50 comprised of a slide dimmer
configuration having a sliding control switch and a power switch
below the sliding control switch.
[0036] FIG. 11 illustrates a basic TRIAC dimming circuit for a
TRIAC dimmer 50 suitable for usage with the present invention. The
potentiometer (POT R) and capacitor (C) combine to create a
phase-shift network that is used to set the TRIAC conduction angle,
thereby determining the amount of power applied to the AC
electrical power load. The potentiometer is adjusted by the user as
a slide, knob or button on the dimmer itself As the capacitor is
charged, it will exceed the DIAC's break over voltage, at which
point the DIAC will begin to conduct electricity to the TRIAC's
gate, triggering the TRIAC to conduct. Typical DIAC break over
voltages range between 20V and 40V. As the potentiometer's
resistance is decreased, the DIAC's break over voltage is achieved
more readily, thus activating the TRIAC sooner. The faster the
TRIAC conducts, the more power is delivered to the load (e.g.
incandescent lights). Once activated, the TRIAC conducts
electricity until the current drops below the TRIAC 's holding
current, typically on the order of 10's of milliamps. With this
information, it can be shown that by applying a voltage greater
than the DIAC's break over voltage across the TRIAC dimmer 50, the
position (0% to 100%) of the potentiometer can be determined by
measuring the amount of time required to charge the capacitor
beyond the DIAC's break over voltage and activate the TRIAC. Due to
the AC design of conventional TRIAC dimmers 50, the polarity of the
applied voltage does not matter as illustrated in FIGS. 3 and 5 of
the drawings.
[0037] The TRIAC dimmer 50 is comprised of a first main terminal
and a second main terminal referenced as Hot, Black or Black Wire
in FIGS. 3, 4 and 11 of the drawings. The first main terminal and
the second main terminal are the electrical terminals of a
conventional TRIAC dimmer 50 that are typically electrically
connected with the AC power source (e.g. power line) electrically
connected to the first main terminal and the load electrically
connected to the second main terminal (of course in the present
invention no such connection is used). The TRIAC dimmer 50
typically includes a ground terminal which is typically comprised
of a green wire (referenced as Ground and Green in FIGS. 3-4 of the
drawings). The ground terminal is utilized for grounding the TRIAC
dimmer 50 in conventional AC applications. The ground terminal of
the TRIAC dimmer 50 as used in the present invention may not be
electrically connected to anything and may be insulated with
electrical tape. It is preferable that the ground terminal of the
TRIAC dimmer 50 not be connected to anything, but not required.
[0038] The analyzer 32 is electrically connected to the first main
terminal and the second main terminal of the TRIAC dimmer 50 to
apply the test voltage to the TRIAC dimmer 50 and to determine when
the TRIAC dimmer 50 begins to conduct electricity. FIGS. 3 and 4
illustrate a test voltage of 48V DC applied to the TRIAC dimmer 50
at two different polarities.
E. Control Unit
[0039] The control unit 30 is comprised of an electronic device
capable of determining the state of the TRIAC dimmer 50 and dimming
the low voltage lighting 40. The control unit 30 may be an
individual standalone unit that is electrically connected to the
TRIAC dimmer 50 and the low voltage lighting 40 as illustrated in
FIGS. 1 and 2 of the drawings. Alternatively, the control unit 30
may be directly integrated within the housing 22 of the low voltage
power supply 20 as illustrated in FIGS. 7 and 8 of the drawings. As
another alternative, the control unit 30 may be directly integrated
within the lighting fixture 42 of the low voltage lighting 40 as
illustrated in FIG. 9 of the drawings. The control unit 30
preferably includes a microprocessor and is electrically connected
to the low voltage power supply 20 and/or the AC power supply 12.
The control unit 30 may be comprised of a computer capable of
receiving, storing and transmitting data.
[0040] As illustrated in FIG. 2 of the drawings, the control unit
30 is comprised of a TRIAC analyzer 32 (referred to as only an
analyzer 32 herein) that analyzes the state of the TRIAC dimmer 50
and a low voltage dimmer 34 that controls the luminosity of the low
voltage lighting 40. The analyzer 32 communicates with the low
voltage dimmer 34 to control the DC output voltage of the low
voltage dimmer 34 thereby controlling the brightness level of the
low voltage lighting 40. The communications between the analyzer 32
and the low voltage dimmer 34 may be unilateral from the analyzer
32 to the low voltage dimmer 34 via a control signal or
bidirectional.
[0041] The analyzer 32 and the low voltage dimmer 34 are preferably
integrated into a single device, however, the analyzer 32 and the
low voltage dimmer 34 may be comprised of two completely separate
devices. For example, the analyzer 32 may be comprised of a
wireless device that is electrically connected to the TRIAC dimmer
50 and in wireless communication with the low voltage dimmer 34
which is in a different physical location to control the low
voltage lighting 40. In addition, the analyzer 32 may also
communicate (wirelessly or wired) with one, two or more low voltage
dimmers 34 to control one or more systems of low voltage lighting
40.
F. Low Voltage Dimmer
[0042] The low voltage dimmer 34 may be comprised of any convention
dimmer capable of controlling the level of brightness of low
voltage lighting 40. It is preferable that the low voltage dimmer
34 be comprised of an LED dimmer to control light emitted from LED
based lighting such as a pulse-width modulation (PWM) LED dimmer or
an analog LED dimmer. The low voltage dimmer 34 may be integrally
part of the control unit 30 and/or the analyzer 32, or the low
voltage dimmer 34 may be completely separate from them. The low
voltage dimmer 34 may also be integrally formed with the low
voltage power supply 20 as shown in FIG. 7 of the drawings or
integrally formed with the lighting fixture 42 of the low voltage
lighting 40 as illustrated in FIG. 9 of the drawings.
[0043] The low voltage dimmer 34 is in communication with the
analyzer 32 either wired or wirelessly (e.g. WI-FI, BLUETOOTH based
wireless technologies). The analyzer 32 transmits a control signal
to the low voltage dimmer 34 specifying a DC output voltage for the
low voltage dimmer 34 to correspondingly control the brightness
level of the low voltage lighting 40. The DC output voltage may be
comprised of pulse-width modulation (PWM) if using a PWM LED
dimmer. The DC output voltage may be comprised of a voltage level
control (e.g. 12V DC when the TRIAC dimmer 50 state is determined
to be in a 100% power position, 6V DC when the TRIAC dimmer 50
state is determined to be in a 50% power position and 0V DC when
the TRIAC dimmer 50 state is determined to be in a 0% power
position). The DC output voltage may also be comprised of a current
limiting functionality wherein the voltage of the DC output voltage
remains the same (e.g. 12V DC) but the amount of current allowed to
be provided is limited to the corresponding state of the TRIAC
dimmer 50 (e.g. the maximum current is allowed when the TRIAC
dimmer 50 state is determined to be in a 100% power position and no
current is allowed when the TRIAC dimmer 50 state is determined to
be in a 0% power position).
G. Analyzer
[0044] The TRIAC analyzer 32 (referred to throughout as analyzer
32) is adapted to apply a test voltage to the TRIAC dimmer 50 and
to measure a period of time required for the TRIAC dimmer 50 to
start conducting electricity after applying the test voltage. The
analyzer 32 calculates a state of the TRIAC dimmer 50 (e.g.
position of the control switch) based upon the period of time
required for the TRIAC dimmer 50 to start conducting electricity
after applying the test voltage. In an alternative embodiment, the
analyzer 32 determines that the TRIAC dimmer 50 is conducting
electricity when the TRIAC dimmer 50 conducts a minimum electrical
current when the test voltage is applied. Through testing, the
applicant has determined that a preferred minimum electric current
is comprised of at least 50 milliamps (mA), however, greater or
less than 50 milliamps may be used for the minimum electrical
current threshold. The analyzer 32 may be comprised of any
electrical device capable of receiving, storing and/or transmitting
data such as a computer. The analyzer 32 preferably includes a
microprocessor that calculates the state of the TRIAC dimmer 50
along with other functions of the analyzer 32.
[0045] The analyzer 32 measures, calculates and determines what
percentage the TRIAC dimmer 50 is set to by a user such as between
0% to 100% with 0% being low or no illumination and with 100% being
full illumination of the low voltage lighting 40 and proportionally
in between thereof. FIGS. 7 and 8 illustrate a sliding dimmer being
used for the TRIAC dimmer 50 wherein the sliding control switch is
approximately at 50% wherein the top of the sliding positions would
be 100% and the bottom of the sliding positions would be 0%. The
analyzer 32 calculates the state of the TRIAC dimmer 50 based upon
the period of time measured from the start time of the analyzer 32
applying the test voltage to the end time of the TRIAC dimmer 50
conducting electrical current.
[0046] The test voltage applied by the analyzer 32 is preferably
comprised of a DC voltage sufficient to cause the TRIAC dimmer 50
to conduct electrical current. The applicant has learned through
testing that the test voltage should be greater than 30V DC (even
though it could be less) and is further preferred that the test
voltage is at least 48V DC to ensure an accurate and consistent
period of time for the TRIAC dimmer 50 to start conducting is
measured. The chart in FIG. 10 was developed testing five different
positions of a conventional TRIAC dimmer 50 (LEVITON.RTM.
SURESLIDE.RTM. 6672) to determine the period of time for the TRIAC
dimmer 50 to start conducting at least 50 milliamps when the test
voltage applied is 48V DC. As further shown in FIG. 10 of the
drawings, the period of time for the TRIAC dimmer 50 to begin
conducting 50 milliamps is approximately linear and is inversely
proportional to the state of the TRIAC dimmer 50.
[0047] The analyzer 32 removes the test voltage for a discharge
time from the TRIAC dimmer 50 after the TRIAC dimmer 50 starts to
conduct electricity to allow the TRIAC dimmer 50 to discharge to
ensure an accurate next measurement of the state of the TRIAC
dimmer 50 by the analyzer 32. The discharge time is at least an
amount of time sufficient to allow the capacitor C in the TRIAC
dimmer 50 to discharge. The discharge time is preferably at least
50 milliseconds which the applicant has determined is a sufficient
time to allow the TRIAC dimmer 50 to discharge, however, the
discharge time may be greater than, less than or equal to 50
milliseconds.
[0048] The analyzer 32 again applies the test voltage after the
discharge time. The process of applying the test voltage and
removing the test voltage for a discharge time is repeated
continuously to determine the current state of the TRIAC dimmer 50
for at least during a period of time when it is determined that low
voltage DC electrical power is required by the low voltage lighting
40.
[0049] The state of the TRIAC dimmer 50 calculated by the analyzer
32 is comprised of an estimated dimming position for a dimming
switch of the TRIAC dimmer 50. The estimated dimming position is
calculated by the analyzer 32 based upon the period of time that
the TRIAC dimmer 50 takes to conduct electrical current from the
time the test voltage is applied. The analyzer 32 utilizes this
state data to signal to the low voltage dimmer 34 the level of DC
output voltage that should be applied to the low voltage lighting
40 to achieve a corresponding level of brightness from the low
voltage lighting 40. The DC output voltage from the low voltage
dimmer 34 is inversely proportional to the period of time it takes
for the TRIAC dimmer 50 to conduct electricity as illustrated in
FIG. 10 of the drawings.
[0050] The analyzer 32 may be in a wired or wireless communication
with the low voltage dimmer 34. When in wireless communication with
the low voltage dimmer 34, the analyzer 32 is able to be positioned
in a location remote of the low voltage dimmer 34 such as adjacent
to the TRIAC dimmer 50.
[0051] The analyzer 32 may initially be manufactured with a preset
formula for determining the state/position of the TRIAC dimmer 50.
The analyzer 32 may also learn the state/position of the TRIAC
dimmer 50 over time by monitoring the lowest recorded period of
time to conduct a minimum level of electrical current (i.e. this
would be the highest state where the luminosity should be 100% for
the low voltage lighting 40) and the highest recorded period of
time to conduct a minimum level of electrical current (i.e. this
would be the lowest state where the luminosity should be 0% for the
low voltage lighting 40). The analyzer 32 can do a linear
approximation of the period of time between the recorded highest
state and lowest state to provide accurate control over the low
voltage lighting 40 over a period of time. The ability of the
analyzer 32 to learn the different periods of time to conduct
electricity for the TRIAC dimmer 50 allows the analyzer 32 to be
used with various types and brands of TRIAC dimmers 50. In
addition, the ability to learn the different periods of time to
conduct electricity for the TRIAC dimmer 50 allows the analyzer 32
to automatically adjust based upon the characteristics of the TRIAC
dimmer 50 changing over time.
[0052] FIG. 12 illustrates a circuit used by the microcontroller in
the analyzer 32 to control the entire process of the analyzer 32.
The microcontroller controls the 48V line to the TRIAC dimmer 50 by
applying 5V to PulseControl. 48V DC then travels through the 50mA
constant current regulator and to the TRIAC dimmer 50. The
microcontroller then monitors the PulseMeasure, which will drop to
0V as soon as the TRIAC dimmer 50 starts conducting electricity.
Once this change is detected, the PulseControl is pulled back down
to 0V, effectively turning off the 48V line. The time is recorded
and the system is then adjusted accordingly at which point the
process starts over again.
H. Operation of Preferred Embodiment
[0053] In use, a test voltage (e.g. 48V DC) is applied to the first
main terminal and the second main terminal of a TRIAC dimmer 50. A
small amount of electrical current will initially be conducted by
the TRIAC dimmer 50 to charge the capacitor C in the TRIAC dimmer
50.
[0054] After the capacitor C in the TRIAC dimmer 50 is charged, the
TRIAC dimmer 50 will then start conducting a minimum electrical
current (e.g. 20 mA or more). The charge on FIG. 10 utilizes 50 mA
as a minimum electric current while greater or less minimum
electrical currents may be used.
[0055] After the analyzer 32 determines that a minimum electrical
current is being conducted by the TRIAC dimmer 50, the analyzer 32
identifies the end time thereby allowing for the measure of the
period of time between the start time and the end time. In
addition, the TRIAC dimmer 50 removes the test voltage at the end
time or shortly thereafter to allow the TRIAC dimmer 50 to
discharge. The analyzer 32 calculates the current state of the
TRIAC dimmer 50 based upon the period of time measured for the
TRIAC dimmer 50 to conduct a minimum electrical current.
[0056] As shown in FIG. 10, the greater the period of time measured
by the analyzer 32 the lower the state of the TRIAC dimmer 50 is
estimated to be positioned at. In addition, the lower the period of
time measured by the analyzer 32 the greater the state of the TRIAC
dimmer 50 is estimated to be positioned at. Based upon the period
of time, the analyzer 32 is able to calculate the illumination
level that the low voltage lighting 40 should be at and communicate
the illumination data to the low voltage dimmer 34 so that the DC
output voltage from the low voltage dimmer 34 may be adjusted
accordingly to corresponding to the illumination level (and to the
state of the TRIAC dimmer 50). The illumination level of the low
voltage lighting 40 is inversely proportional to the period of time
measured by the analyzer 32.
[0057] After the discharge time, the analyzer 32 repeats the
process of applying the test voltage, determining the period of
time when the TRIAC dimmer 50 starts to conduct electrical current
at a minimum level, measuring the period of time, removing the test
voltage and adjusting the DC output voltage of the low voltage
dimmer 34 accordingly. If there was no change in state of the TRIAC
dimmer 50 compared to the prior measured state of the TRIAC dimmer
50, then the low voltage dimmer 34 maintains the same level of DC
output voltage. If the state of the TRIAC dimmer 50 is determined
to have been lowered by the analyzer 32 from the prior measured
state, then the analyzer 32 instructs the low voltage dimmer 34 to
correspondingly decrease the low voltage lighting 40 by lowering
the DC output voltage which lowers the luminosity of the low
voltage lighting 40. If the state of the TRIAC dimmer 50 is
determined to have been increased by the analyzer 32 from the prior
measured state, then the analyzer 32 instructs the low voltage
dimmer 34 to correspondingly increase the low voltage lighting 40
by increasing the DC output voltage which correspondingly increases
the luminosity of the low voltage lighting 40. As discussed
previously, the DC output voltage may be adjusted using PWM or
analog for LED based lighting.
[0058] Unless otherwise defined, all technical and scientific terms
used herein have the same meaning as commonly understood by one of
ordinary skill in the art to which this invention belongs. Although
methods and materials similar to or equivalent to those described
herein can be used in the practice or testing of the present
invention, suitable methods and materials are described above. All
publications, patent applications, patents, and other references
mentioned herein are incorporated by reference in their entirety to
the extent allowed by applicable law and regulations. The present
invention may be embodied in other specific forms without departing
from the spirit or essential attributes thereof, and it is
therefore desired that the present embodiment be considered in all
respects as illustrative and not restrictive. Any headings utilized
within the description are for convenience only and have no legal
or limiting effect.
* * * * *