Download Switching Comparison: NexLight

NexLight® LIGHTING CONTROL SYSTEM
NexLight
Low Voltage Lighting Control System
vs.
Conventional Low Voltage Switching
Product Feature Comparison
This document compares NexLight’s advanced Low Voltage Lighting Control System to
conventional low voltage lighting control systems, including General Electric’s TLC
system. While appearing to offer similar functions, they are based on very different
system devices and architectures, each with unique features and benefits. We believe
that the NexLight® system not only advances the state-of-the-art for lighting control, with
superior technology, workmanship, and quality, but delivers real and lasting value both
to installing contractors and to end-users over the implementation and operational life of
this very critical building component.
NexLight® is a registered trademark of NORTHPORT ENGINEERING INC., Pub No. 0023, 01/26/01
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NexLight® LIGHTING CONTROL SYSTEM
Here is a brief background of the low voltage market and how it has developed over the
years:
Early 60’s:
Lighting control systems are marketed in which low voltage relays and
switches are “hard-wired” to each other for line voltage circuit control.
Subsequent enhancements included grouping of relays while still
allowing individual control, and the addition of input modules for control
by other devices such as time clocks or photocells.
70’s – 80’s: Programmable Lighting Control Systems appeared from GE,
Westinghouse, TouchPlate, and others. They offered master control of
relay groups for automatic switching. Individual relays were still hardwired to switches for control. Later enhancements included “soft-wired”
systems wherein switch-to-relay assignment was programmable.
Intelligence was confined to the relay panel.
Early 90’:
NexLight introduces the next generation of lighting control with
distributed intelligence in all devices (a fully-addressable system). Each
device connects to a simple two-wire signal bus and is identified by
specific addresses. Any relay or relays can be controlled by any switch
or switches or other input device via a simple address setting.
Installations are accomplished quickly and easily without concern about
switch terminations. Systems are easily set-up and can later be
reconfigured to accommodate owner’s changing needs without costly rewiring. Personal Computers can be added to the system to easily
operate and monitor all aspects of a building’s lighting needs.
Some key differences between NexLight’s System and conventional Low Voltage
Lighting Control Systems such as GE’s are listed on the following pages.
NexLight® is a registered trademark of NORTHPORT ENGINEERING INC., Pub No. 0023, 01/26/01
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NexLight® LIGHTING CONTROL SYSTEM
Switching Comparison: NexLight® vs. Conventional Systems
NexLight:
Conventional Systems:
√ Intelligent switches include microchip
addressing and communications
functions to issue commands and
receive and display load status
information.
•
Standard mechanical switches (3
position, momentary contact)
provide contact closure to switch
inputs at the relay panel.
√ Switches and relays communicate via a
non-polarized two-wire signal bus. The
two-wire bus is distributed in any
convenient manner including Looping,
T-tap, or Star method and is terminated
without regard for polarity.
•
Each switch has 3 low voltage
wires between the switch and relay
panel; 2 additional wires are
needed for optional status display.
Careful attention must be paid to
color-coding of individual
conductors.
√ Switches are easily added to an existing
system by simple drop-down of two
wires from any convenient place on the
signal bus.
•
Switches are added by pulling at
least 3 wires back to the
appropriate relay panel, and
require that a spare switch input is
available.
√ Switches and relays are associated by
addressing: some models use a simple
DIP-switch setting; others accept
wireless infrared signals for instant setup from the front of the device. Any
switch can control any circuit(s) by
simply changing its address.
•
Association of switches and relays
for the GE system is determined
primarily (i.e. except for Groups)
by their positions as initially wired
into the relay panel. Any changes
to switch and/or relays inside the
relay panel.
√ True load status is communicated
instantly signal bus-wide and is
displayed on LEDs built-in to every
switch; Red=On, Green=Off. No
additional wiring is required for status
displays.
•
Wall switch Load Status display is
optional, and uses a single LED to
indicate only if load is On. Two
additional low voltage wires are
required per switch, plus a
separate power supply.
√ Up to 4 buttons (total of 8 LEDs) per
switch assembly install in a single-gang
opening (1-, 2-, 3-, and 4-button models
available).
•
Only one- or two-button switches
for single gang opening in GE
system. Two buttons require 8
wires returned to relay panel vs. 2
for NexLight.
NexLight® is a registered trademark of NORTHPORT ENGINEERING INC., Pub No. 0023, 01/26/01
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NexLight® LIGHTING CONTROL SYSTEM
√ Master Switch Panel devices provide
central control and On-Off status display;
6 models of 20, 24, 44, 48, 68, or 72
buttons each. Only two wires needed to
connect to signal bus; no additional
wiring (e.g. power) is required.
•
Master Switch Panels are not
offered; similar functionality is
custom-fabricated with 3 wires
required for each switch plus
additional wiring for On status
display.
√ Circuits anywhere in the building are
easily grouped for On-Off control from
any location. Multiple switches can
control; the same load(s); switches or
PC always display true load status
regardless of command origin.
•
Grouped circuits are limited to the
relay panel location and may
require complex wiring of blocking
diodes; grouped circuits in different
panels (locations) require
additional wiring to the remote
relay panels.
√ Circuits from anywhere in the building or
system are easily programmed into
Patterns of On, Off, and Dimmed states
and controllable from any switch location
by a single button-press.
•
Additional switches and complex
wiring can approximate a pseudoPattern function. True pattern
(scene-setting) function from
individual buttons requires a
central controller & software.
√ Incandescent Dimming; switches include
individual Bright, Dim, and On-Off
buttons plus LEDs for dimming level
display, On-Off status.
•
Dimming function not available.
√ Wireless (infrared) remote control
available for any load including dimmed
incandescent.
•
Wireless remote control not
available.
√ Both Commercial-style, Designer-style,
•
and Glacier-style switches are available
for maximum design flexibility. Screwless
wallplate design.
Commercial-style Pushbutton,
Toggle, and Rocker-style switches
for a variety of wallplates.
√ Buttons are designed to accept custom
label inserts for easy identification of
switched load.
External labels (e.g. Dymo® brand
tape) are applied to outside of
switch plates.
•
NexLight® is a registered trademark of NORTHPORT ENGINEERING INC., Pub No. 0023, 01/26/01
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NexLight® LIGHTING CONTROL SYSTEM
Relay Comparison: NexLight® vs. Conventional Systems
NexLight:
Conventional Systems:
√ 20 Amp mechanically-latching relays are
available in both single- and double-pole
models.
•
20 Amp mechanically-latching
relays are available in only singlepole models.
√ 20A relays include built-in manual
operating lever for fingertip control of On
or Off status of connected load.
•
No manual operating capability.
Local override can only be
accomplished by hardwiring-in
additional external override
switches.

Fully-operational On-Off lever
eliminates need to temporarily
bypass low voltage system relays
during building construction while
awaiting completion of interior
walls.

Electricians must bypass
relays during building
construction and delay final
termination until interior walls
are complete and switches
are installed and wired.

Relays can be manually operated at
the relay panel by building
operating personnel for any reason.
LEDs or PC reflect status changes.

Additional electrical switches
must be mounted and wired
to allow local override of
lighting relays by building
personnel.
√ The 20A relay’s manual On-Off lever
provides clear visual indication of On or
Off position.
•
No manual operating capability
and no visual indication of relay
position.
√ True relay On-Off status is
communicated instantly signal bus-wide
and displayed on LEDs built-in to every
switch; Red=On, Green=Off. No
additional wiring or power is required for
status displays.
•
Relay status (On only) can be
reported to pilot lights through use
of optional auxiliary (pilot)
contacts. Requires separate wiring
and also additionally separate
power supply for some models.
√ 20A relays are fully rated for HID (High
Intensity Discharge) loads at 277 Vac.
•
Not fully rated for 20A HID loads at
277 Vac.
√ 20A double pole relay, fully rated for HID
(High Intensity Discharge) loads at 480
Vac (WR6172).
•
Not fully rated for 20A HID loads at
480 Vac.
NexLight® is a registered trademark of NORTHPORT ENGINEERING INC., Pub No. 0023, 01/26/01
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NexLight® LIGHTING CONTROL SYSTEM
√ NexLight’s 20A relays are of superior
construction and can be switched over
30,000 times at full-rated load. Other
quality features include:
•
Compare the NexLight 20 Amp
relay’s construction features listed
at left to the General Electric RR 7
relay below:

Current-carrying contacts are 0.221
inches in diameter and 0.0384 sq.
inches in area.

Current-carrying contacts are
0.189 inches in diameter and
0.0281 sq. inches in area.

Open-contact gap is 0.136 inches.

Open-contact gap is 0.020
inches (2).

Coil-clearing contacts are Standard.

Coil-clearing contacts Not
Available.

Bus conductor material is Copper.

Bus conductor material is
Alloy

Internal bus smallest crosssectional area is 0.155 x 0.041
inches, area of 0.00636 sq. inches*.

Internal bus smallest crosssectional area is 0.008 x
0.062 inches x 2, area of
0.00099 sq. inches*.
Note: *Area of #12 AWG wire is 0.00513
sq. in.

Note: *Area of #12 AWG wire is
0.00513 sq. in.

Terminal Type for Power wires is
Phillips/Slotted with Pressure
Plates. Terminal type for
Signal/Control wires is
Phillips/slotted with Pressure
Plates. Staggered for easy wiring.
Terminal type for Power wires
is Slotted with Pressure
Plates. Terminal Type for
Signal/Control wires is
Pigtails/Wire Nuts.
√ NexLight includes 6A relay units with 4
•
independent relays and a local manual
override switch. These are ideal for
splitting 20A circuits for control of smaller
loads such as individual offices.
6A relays are not available.
√ 6A relays require no additional power
(only the-two signal bus wires) & thus
are ideal for remote-mounting and
distribution.
6A relays are not available.
Remote mounting of relays not
convenient or cost-effective due to
wiring requirements.
•
NexLight® is a registered trademark of NORTHPORT ENGINEERING INC., Pub No. 0023, 01/26/01
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NexLight® LIGHTING CONTROL SYSTEM
Other Comparisons: NexLight® vs. Conventional Systems
NexLight:
Conventional Systems:
√ Multiplexed transmission technology
•
radically simplifies system design, wiring,
terminations, setup, and checkout.
Wiring of “smart” switches is simple;
assignments of switches to circuits can
wait until installation is complete.
Subsequent changes and maintenance
are extremely simple.
Relays and switches are typically
hard-wired together for direct OnOff control, with significantly
complex design, wiring,
termination, setup, checkout, and
troubleshooting cost & effort
required. Future changes,
additions, and maintenance are
difficult and costly.
√ Addressing information is stored in each
device, Group and Pattern information is
stored at system level and time
schedules are stored at the BMS, Time
Clock, or PC level.
•
Logic boards are required at each
relay panel to perform time
schedule function of Group &
Pattern programming.
√ System parameters are automatically
captured to nonvolatile EEPROM
eliminating need for costly and
troublesome battery backup; provides
safe, long-term retention of all critical
addressing & control information.
•
System parameters are stored in
volatile RAM – external battery
back-up is required. Critical
addressing & control information is
subject to potential battery failure;
batteries require testing,
maintenance, and replacement.
√ Timer function available for any switch
turns lights On for predetermined time
after switch is turned On. Off-delay
function keeps lights On for
predetermined time after switch is turned
Off.
•
Timer function available for any
switch turns lights On for
predetermined time after switch is
turned On. Off-delay function is not
available
√ Personal Computer may be incorporated
to extend functionality to full centralized
control:
•
Personal Computer may be
incorporated to extend functionality
to full centralized control:

Compatible with many Building
Management Systems and
Manufacturers (see Application
Note).

Consult individual
manufacturing specifications.
NexLight® is a registered trademark of NORTHPORT ENGINEERING INC., Pub No. 0023, 01/26/01
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NexLight® LIGHTING CONTROL SYSTEM

Monitoring and On-time analysis of
all system status changes, including
wall switch operations, occupant
sensor cycling, manual relay
overrides, etc. All status changes
are accounted for without any
additional wiring involved.

Monitoring of all status
changes requires significant
additional wiring and system
complexity.

Central programming of Group and
Pattern functions.

Consult individual
manufacturer’s specifications.

Scheduling functions including
separate daily schedules, annual
holidays, special non-repeating
dates, etc. Includes astronomical
clock and automatic daylight
savings & leap year actions.

Consult individual
manufacturer’s specifications

Logging functions include last time
On, last time Off, on-time
accumulation, etc. Tracks on-times
in both Occupied and Unoccupied
time-of-day categories.

Consult individual
manufacturer’s specifications.

After-hours overrides and tenant
billing capability. Includes ability to
allocate shared loads among
multiple tenants using different
square footage.

Consult individual
manufacturer’s specifications.

Push-button telephone override,
Dynamic color graphics display,
and Remote telecommunications
options are also available.

Consult individual
manufacturer’s specifications.
√ Uncommonly high system reliability,
NexLight components and systems have
experienced virtually zero failures in
normal everyday use, over years of
service and hundreds of installations
worldwide.
•
Reliability varies widely by
manufacturer. Failures and
problems in day-to-day use are
extremely impactive and costly to
tenants and owners; consult with
individual manufacturers for
specific reliability data and track
records.
NexLight® is a registered trademark of NORTHPORT ENGINEERING INC., Pub No. 0023, 01/26/01
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