FIELD OF THE INVENTION
[0001] This invention is related generally to lighting systems, and more particularly to
LED-based low-voltage lighting systems and fixtures for such systems.
BACKGROUND OF THE INVENTION
[0002] There is continuing pressure for the reduction of overall power consumption and movement
toward "green" technologies within the lighting industry. This invention is directed
toward meeting the demands of both of these ideals in the area of general lighting
through the use of LED-based luminaire systems. The invention is a complete LED lighting
system that makes innovative use of new LED technology and low-voltage, remotely-located
power drivers/controllers and commonly-available communication network cabling and
the corresponding standard connectors used with such cabling. Communication network
cabling, typically comprising four twisted pairs of conductors, has become a low-cost
commodity item as have the standard connectors used with such cabling. Because the
voltage used in such cabling (and power units connected thereto) is low-voltage, the
skill level (and cost per hour) of the installers is low, providing strong incentive
for utilization of such a cost-effective system. Also, the ease of interconnection
available with the standard network connectors further reduces the time required for
installation.
[0003] The resultant lighting systems can provide at least 50% reduction in power consumption
aggregately over current lighting systems, with an efficient, consistent and uniform
realized lumen output. Adoption of this approach by an end-user reduces initial installation
costs by using simple cable feeds without the need of conduit and by exploiting the
quick-connection aspects of the standard connectors. By using LEDs with, for example,
a 50,000 hour (minimum) maintenance-free life, the inventive lighting system provides
superior installation simplicity and system performance using a comparatively "green"
technology with a substantial reduction in "total-cost-of-ownership per unit area
of application space" for the end-user.
OBJECTS OF THE INVENTION
[0004] It is an object of this invention, in the field of lighting systems, to provide LED
lighting systems which substantially reduce the total-cost-of-ownership per unit area
of application space served for the end-user.
[0005] Another object of this invention is to provide LED lighting systems which utilize
only communication network cabling and standard network connectors for system connections.
[0006] Another object of this invention is to provide LED lighting systems which limit the
power driver output voltage and power to the limits prescribed by the Class 2 power
supply standards.
[0007] Another object of this invention is to provide LED lighting systems which are flexible
and reconfigurable.
[0008] Another object of this invention is to provide LED lighting systems which utilize
only a small number of elements which, when interconnected, permit a wide variety
of lighting system architectures.
[0009] Another object of this invention is to provide LED lighting systems which require
a low skill level for the installers of the systems.
[0010] These and other objects of the invention will be apparent from the following descriptions
and the drawings.
SUMMARY OF THE INVENTION
[0011] The term "shift module" as used herein describes a building block used within the
inventive LED lighting system to shift the connections of an input network connector
of a shift module in order to enable the driver initially connected to one conductor
pair within a connected cable to be connected to another position in an output network
connector of the shift module. Details of a shift module are further described below.
[0012] The term "star module" as used herein describes a building block used within the
inventive LED lighting system to distribute the connections of an input network connector
of a star module to multiple output network connectors of a star module in order to
enable the drivers initially connected to the conductor pairs of the connected input
cable to each be connected to a separate output network connector. Details of a shift
module are further described below.
[0013] The term "terminated" as used herein describes an LED fixture in which the pair of
conductors which is connected to the LEDs of the fixture is shorted, e.g., with a
jumper or switch, at the output side of the LED fixture to allow electrical current
to flow through the conductor pair. Further detail on such termination is described
below.
[0014] The term "communication network cabling" as used herein refers to the commonly-available
network cabling consisting of multiple pairs of conductors. For example, very commonly
used Category 5 (and Category 5e) cabling includes four twisted pairs of conductors.
Other communication network cabling, such as Category 2 and Category 6 cabling, is
also intended to be described by the term "communication network cabling" as used
herein, as is other low-voltage, multi-pair cabling with either twisted or non-twisted
pairs. The most common standard cable, Category 5 (or 5e) cabling, is often referred
to as Cat 5 cable.
[0015] The term "standard network connectors" as used herein refers to the network cable
connectors used as connectors for communication network cabling. For example, connectors
typically used with Cat 5 cabling are often referred to as RJ45 connectors. More generally,
four-conductor-pair cabling uses connectors referred to as 8P8C connectors. The standard
shape and dimensions of standard 8P8C network connectors are specified by the Administrative
Council for Terminal Attachment (ACTA) in national standard ANSI/TIA-968-A. Standard
8P8C network connectors come in two forms, a male plug and a female socket. The connectors
used with communication network cabling having other than four conductor pairs are
also intended to come under the descriptor "standard network connectors" as used herein.
[0016] The term "DIP switches" as used herein refers to dual in-line package switches well
known to those skilled in the art of circuit design.
[0017] The invention disclosed herein is a low-voltage LED lighting system comprising (a)
at least one LED lighting fixture each having one or more LEDs, (b) at least one power
driver remote from the fixture(s), and (c) interconnections between the at least one
fixture and the at least one power driver using communication network cabling and
standard network connectors.
[0018] In preferred embodiments of the inventive LED lighting system, the at least one fixture
has a plurality of LEDs connected in series.
[0019] In some preferred embodiments, the interconnections include at least one shift module
paired with a fixture. In other preferred embodiments, the interconnections include
at least one star module paired with a fixture.
[0020] Some embodiments of the inventive LED lighting system include at least one fixture
which is terminated.
[0021] In highly preferred embodiments of the inventive LED lighting system, each of the
power drivers has a Class 2 output voltage limit of 60 volts and a Class 2 output
power limit of 100 watts.
[0022] In other preferred embodiments of the inventive LED lighting system, at least one
of the fixtures further includes an input standard network connector having input
connector contacts, a plurality of output standard network connectors each having
output connector contacts, and an array of switches which are configured to selectively
interconnect the input contacts and output contacts. In some preferred embodiments,
the array of switches comprises DIP switches.
[0023] In highly preferred embodiments of the inventive LED lighting system, the fixture(s)
are recessed fixtures adapted for ceiling mounting.
[0024] The present invention is also a method of installing a low-voltage LED lighting system,
the method comprising (a) providing at least one LED lighting fixture each having
one or more LEDs, (b) providing at least one power driver, (c) installing the driver(s)
at positions remote from the fixture(s), and (d) interconnecting the fixture(s) and
the driver(s) using communication network cabling and standard network connectors,
thereby facilitating efficient lighting system installation with low man-hour requirements
and low installer skill levels. In highly preferred embodiments of the inventive method,
the providing of fixture(s) is providing recessed fixtures adapted for ceiling mounting.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025]
FIGURE 1 is a schematic of a control unit according to this invention.
FIGURES 2A-2C are schematics of a set of building blocks describing the basic functions
of fixtures and connecting modules according to this invention. FIGURE 2A is a schematic
of an LED lighting fixture; FIGURE 2B is a schematic of a shift module; and FIGURE
2C is a schematic of a star module.
FIGURES 3A-3D are schematics of the functional building blocks representing the set
of four basic operational modes of fixtures and connections to provide interconnectivity
capable of a wide range of lighting system architectures, of which the schematic of
FIGURE 9 is one example. FIGURE 3A is a schematic of Mode 1 operation, with an LED
lighting fixture which in series with, for example, a neighboring fixture connected
to its output and passing other driver lines through the fixture.
FIGURE 3B is a schematic of Mode 2 operation, with an LED lighting fixture located
at the end of a driver line and passing other driver lines through the fixture.
FIGURE 3C is a schematic of Mode 3 operation, with an LED lighting fixture at the
end of a driver line and using a shift module to shift other driver lines for connections
to additional LED fixtures.
FIGURE 3D is a schematic of Mode 4 operation, with and LED lighting fixture at the
end of a driver line with other driver lines being connected to separate connectors
through the use of a star module.
FIGURE 4A is a schematic of an integrated LED lighting fixture flexibly configured
by a switch array to be able to perform the functions of all four basic operational
modes.
FIGURE 4B is a table specifying the connections realized by the switch array in the
fixture of FIGURE 4A.
FIGURE 4C provides a labeling legend to the operation of the switch array of FIGURE
4A.
FIGURE 5 is a perspective drawing of one embodiment of the inventive LED lighting
fixture of this invention.
FIGURE 6 is a perspective drawing of one alternative embodiment of the inventive LED
lighting fixture of this invention.
FIGURE 7 is a perspective drawing of an integrated LED lighting fixture flexibly configured
by a switch array to be able to perform the functions of all four basic operational
modes.
FIGURE 8 is a perspective drawing of an automatically-configurable fixture having
one pair of conductors for data.
FIGURE 9 is a schematic of an example system of LED lighting fixtures according to
this invention.
FIGURE 10 is a schematic of a representative LED lighting fixture having two series-connected
sets of LEDs, one connected to a first pair of driver lines and the other connected
to a second set of driver lines.
FIGURE 11 is a schematic of a representative LED lighting fixture having parallel
sets of series LEDS, in this case two sets, connected one each to the "in" and "out"
lines of a driver conductor pair.
FIGURE 12 is a schematic of a representative LED lighting fixture having two parallel
sets of series LEDs, both of which are connected to the same conductor of a driver
conductor pair.
FIGURE 13 is a schematic of a representative smart LED lighting fixture which utilizes
one pair of cable conductors to carry data to control the LED lighting fixture and
all other fixtures on the cable connected to this fixture, either directly or indirectly,
as well as the low level of power required to power the electronic circuitry in the
fixture.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0026] The basic features of the inventive LED lighting system are the use of communication
network cabling with standard network connectors as the interconnecting elements of
the system and the use of power drivers which are Class 2 units (i.e., having output
of low voltage and low power).
[0027] The fundamental features and the performance parameters of LED light sources translate
into certain limitations imposed on the configuration of the fixtures and systems.
For example, with a voltage drop of about 3.15 volts across each LED, a maximum of
18 LEDs in series are able to be driven by a driver limited by the Class 2 voltage
limit of 60 volts. (A small line voltage drop is assumed in this calculation.) 18
LEDs in series consume about 20 watts (@ 350 ma current), well below the 100 watt
Class 2 power limitation. On the other hand, 18 LEDs with a luminous efficacy of,
say, 90 lumens per watt, will provide illumination of about 1780 lumens. In many applications,
such a fixture may have much higher light output than the specific application requires
in a single fixture. Fixtures having both fewer or more LEDs than the exemplary fixture
are possible without bumping up against the Class 2 limitations, and it is, of course,
also possible to drive fixtures at a higher current level than the example of 350
ma.
[0028] LED lighting systems which include recessed lighting fixtures adapted for ceiling
mounting are particularly well suited to benefit from the advantages provided by this
inventive LED system. Recessed lighting fixtures mounted in or on ceilings require
considerable amount of skilled electrical work for installation. With the inventive
system, power drivers and fixtures are simply interconnected with standard communication
network cabling and standard network connectors which snap in and out easily and quickly
and are held positively in place. The inventive system dramatically reduces the amount
of electrical work requiring skilled electricians when compared to the installation
of standard recessed lighting systems. FIGURES 5-8 illustrate LED lighting fixtures
which are adapted for ceiling mounting. A co-owned pending United States Patent Application
Serial No.
12/173,721, entitled "Lens with TIR for Off-Axis Light Distribution" also discloses recessed
LED lighting fixtures which can be included in the inventive lighting system disclosed
herein.
[0029] The general structure of the inventive LED lighting system is described below, referring
to the figures which have been described briefly above. FIGURE 1 schematically illustrates
a remote unit 10 including an DC power supply and controller 14 supplied with AC power
from an AC power source 16, and low-voltage driver modules 12 (eight shown) which
each drive one or more LED fixtures 20 (shown in various forms in FIGURES 2A-3D and
5-13 and with other reference numbers when describing particular lighting fixture
configurations) with DC power through communication network cabling 62 (shown in FIGURE
9) which interconnects each element of the lighting system using standard communication
network connectors 18. Drivers 12 provide DC power which is current-controlled, providing
constant current through the LEDs in each LED fixture 20 with current levels typically
of at least 350 ma. Such commonly-available power sources are well-known to those
skilled in the state of the art of circuit design.
[0030] Power supply and controller 14 provides power of up to 100 watts per channel (per
conductor pair in the cabling), with a voltage limit of 60 volts for dry applications
and 30 volts for wet applications. However, for a variety of design reasons, it is
unlikely that any single driver 12 will be operating at this maximum allowable Class
2 power level.
[0031] Power supply and controller 14 may include the ability to dim each LED fixture 20
connected thereto individually with separate manual dimmer controls (not shown) or
all together with a single manual dimmer control. Control of fixtures 20 may also
be carried out through a programmable portion of power supply and controller 14.
[0032] In the embodiments used to illustrate the inventive LED lighting systems herein,
standard connectors 18 each have four pairs of contacts indicated as a
1a
2, b
1b
2, c
1c
2, and d
1d
2, respectively. In each of the figures herein (except in the embodiment of alternative
fixture 64 of FIGURE 10), contact pair a
1a
2 is shown as the pair of contacts connected to the pair of conductors within which
the LEDs of the LED fixture are contained. This pair of conductors is sometimes referred
to herein as the primary pair of conductors. However, it should be noted that in many
circumstances, it is not necessary that the pair of conductors to which a
1a
2 are connected be the primary pair of conductors or channel.
[0033] FIGURES 2A-2C schematically illustrate a set of building blocks which provide the
interconnect functions needed to create a wide variety of lighting systems architectures
for the inventive LED lighting system. Each of these illustrations is schematic in
nature since the circuit configurations required to achieve these functions is clearly
described by the schematics; the circuitry required to perform these functions is
readily known by those skilled in the art of circuit design. Using these building
blocks, a wide variety number of LED lighting system architectures is possible.
[0034] Each of these building blocks includes a single standard network connector as an
input connector and a single standard network connector as an output connector. Input
connectors are indicated by appending an "i" to the corresponding reference number.
An "o" is similarly appended to indicate an output connector. Such a single-input,
single-output connector embodiment is only by way of example and not intended to limit
the variations of building block possible under the inventive system disclosed herein.
For example, LED fixture 20 of FIGURE 2A has input connector 20i and output connector
20o and includes LEDs 21. Many alternatives are illustrated using fixtures having
a single series of LEDs in the fixture connected to the primary pair of conductors,
in the illustrations all labeled as the conductor pair connected to connector contacts
a
1a
2, as shown in FIGURE 2A. Fixture configurations are not limited to this single pair
of conductors approach, but it is expected that for practical reasons, such an approach
may be advantageous. (For simplicity, conductor pairs and contact pairs are herein
often referred to by the pair of subscripted letters indicating the contact pair to
which the pair of conductors is connected.)
[0035] FIGURE 2B and 2C illustrate two building blocks which optionally may be connected
to LED fixtures 20 in order to configure an array of fixtures in a desired fashion
to create an LED lighting system. The first of these is a shift module 22 shown in
FIGURE 2B. Shift module 22 shifts the connections of conductor pairs within input
connector 22i as shown, thus enabling the driver initially connected to connector
pair positions other than that denoted by a
1a
2 to be connected to subsequent lighting fixtures by connecting to different pairs
of connections within output connector 22o.
[0036] The second of the two building blocks is called a star module 24 (FIGURE 2C), so
named since it has one input connector 24i and three output connectors 24o1, 24o2,
and 24o3, thus allowing "star" configurations of fixtures 20 to be created.
[0037] Arrays of lighting fixtures 20 can be configured using these building block elements
which can also represent physical building blocks for the lighting systems. The functions
which are achieved by the use of these building blocks are illustrated in FIGURES
3A-3D. The four basic functions are referred to as operational modes. The fixture
26 of FIGURE 3A is in operational Mode 1. Fixture 26 simply passes each of the four
pairs of conductors through fixture 26 with the LEDs 27 (four shown) connected in
series in the primary pair of conductors a
1a
2.
[0038] FIGURE 3B illustrates operational Mode 2 in which a fixture 28 is simply at the end
of a conductor pair, driven by the power driver (not shown) which is connected to
the primary pair of conductors of the input connector 28i. Fixture 28 may be the only
fixture thus connected or may be at the end of a chain of fixtures driven by a single
power driver. The pair of connections a
1a
2 of the output connector 28o are connected together to cause the electrical current
to flow through the primary conductor pair. Such a fixture 28 is said to be terminated.
A manual end-of-chain switch 49 illustrated in FIGURE 6 (or a simple jumper) can be
used to provide such termination.
[0039] FIGURE 3C illustrates operational Mode 3, in which the primary pair is terminated
in shift module 22 and the second through fourth pairs are each shifted one position
within output connector 30o. Operational mode 4, shown in FIGURE 3D, describes connections
which places the incoming pairs of conductors in position to drive fixtures connected
downstream to other fixtures or an array of fixtures through output connectors 32o
(three shown).
[0040] One example of an LED lighting system configured by combining these building blocks
and operational modes is illustrated schematically in FIGURE 9.
[0041] A second embodiment of an LED fixture 34 according to this invention is shown in
FIGURE 4A. Fixture 34 integrates all of the functions described by the set of basic
building blocks and functions for a single series array of LEDs 21 in each fixture
20 as has just been described. Fixture 34 is an integrated fixture which is configurable
using a switch array 35. Switch array 35 may be an array of manually-settable DIP
switches.
[0042] This second embodiment is illustrated schematically in FIGURES 4A-4C. FIGURE 4A illustrates
the basic structure, and FIGURE 4C provides the necessary nomenclature for FIGURES
4A and 4B. The schematic representation is used to define the switch connections in
a clear fashion; the corresponding physical array is not shown but is well-understood
by those skilled in the art of circuit design. The functions of switch array 35 are
defined in the table 38 of FIGURE 4B. The four basic modes are achieved simply by
setting the DIP switches according to the assignments in table 38 of FIGURE 4B. Note
that the input and output connectors of fixture 34 are labeled with the letters S
and P, Q and R, respectively (instead of 34i and 34o1, 34o2 and 34o3, respectively,
as is the case throughout this document), in order to simplify the terminology of
table 38.
[0043] FIGURE 4C presents a legend 36 to define the connection points of fixture 34 and
the elements in table 38 defining switch array 35. The connection points labeled N
a1 through N
d1 are the eight connection points of a generic connector N. The various connectors
and corresponding connection points or contacts follow the labeling terminology in
table 38.
[0044] A third embodiment, a variation of fixture 20, involves the addition of electronics
into each fixture, indicated as fixture 76 in FIGURE 13. Each such fixture 76 includes
a single input connector 76i and a single output connector 76o. One pair of conductors,
for example, pair d
1d
2 as shown in FIGURE 13, is used to transmit data to each fixture in an array of fixtures
along with the very small amount of power necessary to run the electronics (not shown)
within each fixture 76. No manual intervention on the part of the installer is required;
all electrical configuration of the system is carried out with an electronic array
of switches similar to switch array 35 in FIGURE 4A but controlled by a portion of
power supply and controller 14 remotely-located from fixtures 76. Each fixture 76
contains an address established at the time of manufacture (or settable after manufacture),
and control unit 14 is configured to "learn" the connectivity of the array of fixtures
and be set according to the desires of the user.
[0045] These general embodiments do not form the complete set of alternatives but simply
illustrate the possibilities which an LED lighting system with remote drivers and
simple interconnection cabling and connectors may utilize.
[0046] FIGURES 5-8 present perspective representations of embodiments of recessed fixtures
adapted for ceiling mounting and described schematically above. FIGURE 5 simply shows
a single input connector 40i (not shown in FIGURES 6 and 7) common to all three embodiments.
FIGURE 6 illustrates the first embodiment of an LED fixture including termination
switch 49. FIGURE 7 illustrates an embodiment of an integrated fixture 50 including
a manually-settable DIP switch array 52. FIGURE 8 illustrates a third embodiment including
an output connector 54o in which one pair of conductors carries data to control an
array of fixtures 54, of which only one is shown.
[0047] As mentioned above, FIGURE 9 illustrates an example of an LED lighting system using
the schematic functions to represent the various interconnections. Only single LED
series fixtures are used in this simple example. The heavy bold lines 62 between elements
represent communication network cabling. Control unit 10 has two "chains" 60t and
60b of fixtures being driven, top chain 60t utilizing all four pairs of conductors
to drive LED fixtures 20 (three shown) and 28 (two shown), and the bottom chain 60b
simply uses three of the driver channels to drive three fixtures 20. The LED fixtures
in FIGURE 9 are also labeled with letters A through H for simplicity.
[0048] Fixtures A and B are controlled as a group and are driven by a
1a
2 (in connector 18a) of top chain 60t. Fixture A is operating in Mode 1, and Fixture
B is operating in Mode 3. Fixture C is driven and controlled by b
1b
2 of a top driver set 61t and is also operating in Mode 3. Fixtures D and E are driven
by the driver and conductors connected to c
1c
2 and d
1d
2 of connector 18a, respectively, and are operating in Mode 2 as terminated fixtures
28. From a bottom set of drivers 61 b, connected through connector 18b, fixtures F,
G and H are each controlled by their own driver channels, as is clearly seen in FIGURE
9. Fixtures F and G are operating in Mode 3, and fixture H is operating in Mode 2.
[0049] FIGURES 10-13 illustrate a few configurational variations which are possible within
the inventive LED fixtures of this invention. Such variations provide even more flexibility
to the lighting system architectures possible according to this invention. These configurations
are not intended to limit the scope of the disclosure but to illustrate the wide range
of possibilities which fit within the concepts upon which these configurations are
based.
[0050] FIGURE 10 is a schematic of a representative LED fixture 64 which has LEDs 66a in
series within the circuit of the driver and conductors (not shown) connected to a
1a
2 within the input connector 64i and output connector 64o and LEDs 66b in series within
the circuit of the driver and conductors (not shown) connected to b
1b
2 within the input connector 64i and output connector 64o. Thus , two power drivers
(not shown) are used to power LEDs 66a and 66b of fixture 64.
[0051] FIGURE 11 is a schematic of a representative LED fixture 68 having parallel sets
of series LEDS 70a and 70b connected one each to the "in" and "out" lines of a driver
and conductor pair (not shown) connected to a
1a
2 of connectors 68i and 68o. For example, if the LEDs are to be driven at 350 milliamps
(ma), then the driver must be capable of providing 700ma to this conductor pair.
[0052] FIGURE 12 is a schematic of a representative LED fixture 72 having two parallel sets
of series LEDs 74a and 74b, both of which are connected to the same conductor of a
driver and conductor pair (not shown) connected to a
1a
2 of connectors 72i and 72o. The current considerations for fixture 68 shown in FIGURE
11 apply to this configuration as well.
[0053] FIGURE 13 is a schematic of a representative LED fixture 76 which utilizes one pair
of cable conductors (the conductor pair connected to d
1d
2) to carry data to control LED fixture 76 and all other fixtures (not shown) on the
cable connected to fixture 76, either directly or indirectly, as well as the low level
of power required to power the electronic circuitry (not shown) in the fixture. Such
a fixture is termed a "smart" fixture. The fixture contains a unique address, assigned
during manufacture of the fixture electronics, which allows the onboard control circuitry,
in conjunction with the controller in the control unit (located remotely), to individually
control each fixture connected in an array of such fixtures.
[0054] While the principles of this invention have been described in connection with specific
embodiments, it should be understood clearly that these descriptions are made only
by way of example and are not intended to limit the scope of the invention.
1. A low-voltage LED lighting system comprising:
at least one LED lighting fixture (20) each having one or more LEDs;
at least one power driver (12) remote from the fixture(s); and
interconnections between the at least one fixture (20) and the at least one driver
(12) using communication network cabling (62) and standard network connectors (18).
2. The LED lighting system of claim 1 wherein the at least one fixture (20) has a plurality
of LEDs connected in series.
3. The LED lighting system of claim 1 wherein the interconnections include at least one
shift module (22) paired with a fixture (20).
4. The LED lighting system of claim 1 wherein the interconnections include at least one
star module (24) paired with a fixture (20).
5. The LED lighting system of claim 1 wherein the system includes at least one fixture
(28) which is terminated.
6. The LED lighting system of claim 1 wherein each of the power drivers has a Class 2
output voltage limit of 60 volts and a Class 2 output power limit of 100 watts.
7. The LED lighting system of claim 1 wherein the fixture(s) are recessed fixtures adapted
for ceiling mounting.
8. The LED lighting system of claim 1 wherein at least one of the fixtures (20) further
includes:
an input standard network connector (i) having input connector contacts;
a plurality of output standard network connectors (o) each having output connector
contacts; and
an array of switches (35) configured to selectively interconnect the input contacts
and output contacts.
9. The LED lighting system of claim 8 wherein the array of switches (35) comprises DIP
switches.
10. The LED lighting system of claim 8 wherein switches (35) of the array are electronically-controlled,
whereby the interconnectivity is electronically settable.
11. The LED lighting system of claim 10 wherein the interconnectivity is electronically
detectable.
12. The LED lighting system of claim 10 wherein:
the network cabling (62) includes a plurality of conductor pairs; and
power for the electronically-controlled switches (35) and data setting the interconnectivity
are transmitted on one conductor pair.
13. The LED lighting system of claim 10 wherein the fixture(s) are recessed fixtures adapted
for ceiling mounting.
14. The LED lighting system of claim 1 wherein a power driver of the at least one power
driver (12) is configured to dim at least a subset of the at least one LED lighting
fixture (20).
15. A method of installing a low-voltage LED lighting system comprising:
providing at least one LED lighting fixture (20) each having one or more LEDs;
providing at least one power driver (12);
installing the driver(s) at positions remote from the fixture(s); and
interconnecting the fixture(s) and the driver(s) using communication network cabling
(62) and standard network connectors (18),
thereby facilitating efficient lighting system installation with low man-hour requirements
and low installer skill levels.