enclature
sidebar on p. 3) to replace incandescent lamps in luminaires with
medium screwbase sockets, such as ceiling- and wall-mounted lumi-
naires, exterior luminaires, recessed downlights, track lighting, and
floor and table lamps. CFL products can reduce energy and mainte-
nance costs compared to incandescent lamps. In fact, manufacturers
often indicate the equivalent incandescent wattage on the packaging of
their CFL products. However, CFL products differ from comparable
incandescent lamps and from each other in size, shape, light output,
power quality, and life. The National Lighting Product Information
Program (NLPIP) produced this issue of Specifier Reports to promote
better understanding of screwbase CFL products and to provide guid-
ance to specifiers on selecting them.
CFLs are fluorescent lamps, that have a tube diameter of 16 millime-
ters (mm) [
5 8
inch (in.)] or less. They are available in various shapes,
as shown in Figure 1. Circular lamps have tube diameters equal to or
Screwbase
Compact Fluorescent
Lamp Products
Energy-efficient alternatives to incandescent lamps
NLPIP Online
NLPIP Online is a new service of the Lighting
Research Center (LRC). The Web site
(www.lrc.rpi.edu) contains a full library of NLPIP
products, including
Specifier Reports, Lighting
Answers, and searchable manufacturers data and
NLPIP test results. Adobe Acrobat Reader, which is
required to view
Specifier Reports and Lighting
Answers, is also available on the Web site. As new
CFL products are tested in the future, the data will
be updated online.
Figure 1. CFL Envelope Shapes
The terms used in this report to describe envelope shapes are:
1
quad;
2
triple tube;
3
four-tube;
4
coiled tube;
5
A-line;
6
circular;
7
square;
8
globe;
9
capsule;
10
reflector. Other envelope shapes (not shown) are referred to as decorative. These
are NLPIPs descriptions; manufacturers might use other terms.
1
2
3
4
5
6
7
8
9
10
Contents
Introduction ....................................................... 1
Performance Characteristics ........................... 4
Human Response ............................................ 11
Application Guides ......................................... 12
Alternative Technologies ............................... 13
Performance Evaluations ............................... 14
Further Information ....................................... 15
Data Table Terms and Definitions ................ 16
Data Tables
Manufacturer-Supplied Data .................... 18
NLPIP Evaluations .................................... 36
Manufacturer Contact Information .......... 42 2
Specier Reports: Screwbase Compact Fluorescent Lamp Products
Figure 4. Modular CFL Products
(Incandescent A-lamp at front center shown for size comparison)
larger than 25.4 mm (1 in.). However, this
report treats them as CFL products
because they are compact in overall size
and can be used as alternatives to incan-
descent lamps.
CFL products are available as either
dedicated or screwbase products. Dedi-
cated CFL products, like linear fluorescent
lamp systems, use a ballast that is hard-
wired to lamp holders within a luminaire.
Because the lamps fit into specially keyed
sockets, only dedicated CFL lamps can be
used in the luminaire.
Screwbase CFL products are available in
two configurations: self-ballasted and
modular. A self-ballasted CFL contains a
lamp and ballast as a single unit. Self-
ballasted CFLs are rated for 6000 to
15,000 hours (h), and when the lamp fails,
the entire unit must be replaced. Figure 2
shows some self-ballasted CFLs with an
incandescent A-lamp.
A modular CFL product consists of two
components: a screwbase ballast and a
replaceable CFL. The ballast and lamp
connect together using a socket-and-base
design, as shown in Figure 3. Unlike the
self-ballasted CFLs, modular CFL products
allow the lamp (rated for 7500 to 15,000 h)
to be replaced without having to discard the
ballast (rated for 20,000 to 150,000 h).
Figure 4 shows some modular CFL prod-
ucts with an incandescent A-lamp.
This new Specifier Reports: Screwbase
Compact Fluorescent Lamp Products
re-
places previous NLPIP publications on
screwbase CFL products and includes
performance data for CFL products that
were available as of July 1997, designed to
fit in a medium screwbase socket, and rated
at or above 13 watts (W). This report
includes NLPIP test data and manufactur-
ers data on self-ballasted CFLs and modu-
lar CFL products that are sold with ballast
and lamp packaged as a single unit.
One manufacturer supplied information
on an electrodeless CFL product. This
report treats it as a CFL product because it
can be used as an alternative to incandes-
cent lamps. However, the technology and
operation of the product (current passing
through an induction coil generates an
electromagnetic field, which excites the
mercury vapor) is different from that of the
other CFL products in this report. Some
sections of the report, such as the discus-
sion of ballasts, do not apply to the elec-
Figure 2. Self-Ballasted CFLs
(Incandescent A-lamp at front center shown for size comparison)
Maximum overall length
(listed in Table 1)
Key
Base
Figure 3. Modular CFL and Ballast Specier Reports: Screwbase Compact Fluorescent Lamp Products
3
trodeless CFL product. Specifiers consider-
ing an electrodeless CFL product should
be aware of its possible advantages, such
as a longer life and silent operation. They
should also consider its possible draw-
backs, such as electromagnetic interfer-
ence. The May/June 1995 issue of Lighting
Futures
(Luo 1995) discusses electrodeless
lamps in detail.
Lamps
As with all fluorescent lamps, CFLs emit
light when low-pressure mercury vapor is
energized inside the lamp, which produces
ultraviolet (UV) radiation. The UV radiation
is absorbed by a phosphor coating on the
inner surface of the lamp, which converts
the radiation to light.
Most modular CFL products have bare
lamps to make it easier to replace the lamp.
Self-ballasted CFLs have either bare or
encapsulated lamps. Encapsulated lamps
(shown on the right side in Figure 2) have a
permanently attached glass or plastic cover,
which is available in globe or capsule shape.
Figure 1 on p. 1 shows examples of different
lamp envelope shapes.
Ballasts
Ballasts provide initial voltage for starting
lamps and regulate lamp current during
operation. They consume a small amount of
energy while performing these functions.
CFL ballasts are either magnetic or
electronic. Magnetic ballasts contain a steel
core and copper coil, and operate lamps at
the power line frequency of 60 Hz. They
weigh from 120453 grams (g) [416 ounces
(oz)]. Electronic ballasts contain a circuit
board and electronic components. They are
generally more efficient and quieter than
magnetic ballasts but can cause electromag-
netic interference. Electronic ballasts
operate lamps at frequencies ranging from
2060 kHz. They usually weigh less than
226 g (8 oz).
Some ballasts can dim CFLs, as dis-
cussed in the Dimming section on p. 11.
Tables 1 and 2 indicate when a ballast is
dimmable. The sidebar Starting Methods
on p. 4 explains the different methods
employed by ballasts to start CFL products.
Nomenclature
Throughout this report,
NLPIP uses the following
nomenclature:
The term
CFL products in-
cludes all self-ballasted and
modular CFL products with a
medium screwbase.
A
CFL is the lamp in a CFL
product, regardless of
whether it is modular or part
of a self-ballasted unit.
A
self-ballasted CFL is an
integrated lamp-ballast com-
bination with a medium
screwbase; this is also known
as an integral CFL or a one-
piece CFL.
A
modular CFL product is the
modular CFL and the modu-
lar CFL ballast operating
together as a unit.
A
modular CFL is a CFL that
fits into a modular CFL
ballast.
A
modular CFL ballast is the
medium screwbase ballast
with a lamp holder (socket)
for a modular CFL.
A
compact fluorescent
reflector lamp product
includes a reflector as either
a permanent or removable
component of the CFL
product.
Accessories
Manufacturers provide accessories such as
diffusers, lenses, and reflectors that attach to
their products to modify the light distribu-
tion. Some manufacturers offer other types
of accessories such as antitheft locking
devices. Some accessories are permanently
attached, while others are removable.
Diffusers are useful accessories for bare-
lamp CFL systems (both modular and self-
ballasted CFLs) where the lamp may be in
direct view and cause glare. Focusing
reflectors and lenses convert the primarily
non-directional light output from a CFL into
more directional light output so that it can
replace a directional incandescent lamp such
as a reflector (R) or a parabolic aluminized
reflector (PAR) lamp. Compact fluorescent
reflector lamp products often are used in
recessed downlight and track lighting
luminaires where a directional light source is
preferred. However, they dont always
perform as well as directional incandescent
lamps. See Specifier Reports: Reflector Lamps
(1994) for a more complete discussion.
Figure 5 shows some typical accessories,
and Tables 1 and 2 on pp. 1835 list accesso-
ries offered by the manufacturers.
Figure 5. Typical Accessories for CFLs
(Incandescent A-lamp and PAR30 lamp in front center shown for size comparison) 4
Specier Reports: Screwbase Compact Fluorescent Lamp Products
Performance
Characteristics
CFL produc