Lighting Information
Whether you're looking for information on do-it-yourself holiday lighting or you're just curious about how we do things, hopefully the following will shed some insight.
Index:
Number of Bulbs to Run on a Single Circuit
Total Number of C7/C9 Lamps or Light Strings
Run on a Single Circuit
Recommended Number of Lights for Outdoor Trees
LED vs. Incandescant Electricity Cost Savings
Report
About C9
and C7 Lighting
Number of Bulbs
to Run on a Single Circuit
(a
single circuit includes all outlets that are connected to a breaker
or fuse. to determine the outlets on a single circuit, you can
turn off one breaker or fuse in your breaker box.... usually there
will be notes next to each one telling you the location of the
circuit. once one is turned off, test the outlets to see which
are not working - all that are not functioning are part of the
circuit you turned off.)
| C7 or C9 Lamp Wattage | Lamps per Outlet | Lamps per 15 Amp Circuit | Lamps per 20 Amp Circuit |
| 2.7 Watts | 300 Lamps | 576 Lamps | 768 Lamps |
| 3.7 Watts | 250 Lamps | 389 Lamps | 519 Lamps |
| 5 Watts | 175 Lamps | 288 Lamps | 384 Lamps |
| 7 Watts | 125 Lamps | 205 Lamps | 274 Lamps |
Total Number of C7/C9 Lamps or Light Strings Run on a Single Circuit
see notation on single circuit above...
| C7 or C9 Lamp Wattage | Lamps per 15 Amp Circuit 1800 Total Watts | Lamps per 20 Amp Circuit 2400 Total Watts | Energy Savings Compared to a 10 Watt Bulb |
| .6 Watts - LED C7 | 2400 Lamps | 3200 Lamps | 94% Savings |
| 1 Watt - LED C9 | 1440 Lamps | 1920 Lamps | 90% Savings |
| 2.5 Watts - Low Energy C7 | 576 Lamps | 768 Lamps | 75% Savings |
| 3.7 Watts - Low Energy C9 | 389 Lamps | 519 Lamps | 63% Savings |
| 5 Watts - Traditional C7 | 288 Lamps | 384 Lamps | 50% Savings |
| 7 Watts - Traditional C9 | 205 Lamps | 274 Lamps | 30% Savings |
| 10 Watts - Traditional C9. | 144 Lamps | 192 Lamps | 0% Savings |
Recommended
Number of Lights for Outdoor Trees
(note that numbers below are
subjective and open to opinion. for deciduous trees that have
lost their leaves, use approximately 75% noted below.
for lighter coverage or canopy wrapping, use approximately 50% of
the numbers noted. for branch wrapping, count on about
130-150%.)
| Tree Height | Mini Lights | C7 Lights | C9 Lights |
| 4' | 150 | 50 | 50 |
| 6' | 300 | 70 | 70 |
| 8' | 550 | 150 | 150 |
| 10' | 700 | 225 | 225 |
| 12' | 1,000 | 300 | 300 |
| 15' | 1,250 | 375 | 375 |
| 20' | 1,500 | 450 | 450 |
| 25' | 1,950 | 900 | 600 |
| 30' | 2,400 | 1200 | 900 |
| 40' | 3,300 | 1,500 | 1,250 |
| 50' | 4,500 | 2,250 | 2,000 |
Another method to determine the amount of C7 or C9
lights to use on trees:
For a minimally lit tree ~ Multiply Height (ft) x Width (ft) x 1.5
For a well-lit tree ~ Multiply Height (ft) x Width (ft) x 3
LED vs. Incandescent Electricity Cost Savings Report
| Hours | Bulb Count | 30 Day Cost | 45 Day Cost | Bulb Life | |
| C9 | 8 | 200 | $ 34.95 | $ 52.42 | 13 years |
| Mini | 8 | 300 | $ 3.00 | $ 4.50 | 6 years |
| C9 LED | 8 | 200 | $ 3.80 | $ 5.70 | 833 years |
| Mini LED | 8 | 300 | $ 0.30 | $ 0.44 | 417 years |
| Total Incandescent Cost | $ 37.94 | $ 56.92 | ||
| Total LED Cost | $ 4.10 | $ 6.15 | ||
| LED Savings | $ 33.85 | $ 50.77 | ||
| Calculation Assumptions: |
| 10.4 (Cents per Kilowatthour W/Taxes) 2006 US Average Retail Residential Price |
| C9/C7 3,000 Hours avg. life, Mini/Net/Icicle 1,500 Hours avg. life |
| LED C9/C7 200,000 Hours avg. life, Mini/Net/Icicle 100,000 Hours avg. life |
C7 and C9 Outdoor Christmas Lights are larger than small mini-style
Christmas lights and are often considered traditional outdoor
Christmas
lights. Traditional
C9 and C7 Lights are
heavier-duty than mini-lights and are more reliable.
Christmas C7 and C9 bulbs screw into a candelabra base socket and
can be replaced with standard Christmas bulbs called lamps. These
"traditional" light strings are designed in such a way that if a
single bulb fails, it only affects that bulb. Individuals often use
C7 or C9 Light Strings to decorate large outdoor Christmas trees,
outline building perimeters or simply to decorate the outside of
their homes. Both C7 and C9 lamps or bulbs come in a variety of
colors while the base socket and wire can be purchased in green or
white.
What are the differences between C7 and C9 Outdoor Christmas
Lights?
The
main differences between C7 and C9 Christmas lights are the bulb or
lamp size, base size, and the wattage. C7 bulbs are smaller than C9
bulbs with C7 bulbs just over 2 inches, while C9 bulbs are just over
3 inches long. C7 lamps come in 2.5
Watts and 7
Watts
while C9 lamps are 3.5
Watts and 7
Watts.
C-9 Lights are useful for decorating buildings, particularly those
that are 2 stories or more, as these bulbs appear to shine brighter
and seem more visible from a distance.
What are the differences between different base sizes on light
bulbs?
The commonly used light bulb bases in holiday lighting are
candelabra base and intermediate base. A C7 bulb has the smallest
base called a candelabra base and a C9 bulb has a larger base called
an intermediate base. For each type of base, there is a
corresponding socket size. For example, a light bulb with a
candelabra base will fit only a candelabra socket. Therefore, when
purchasing light strings, be sure to purchase bulbs with compatible
bases. If you purchase light strings with intermediate sockets, be
sure that the light bulbs you purchase also have a intermediate
base.
How many sets of C7 or C9 Christmas Light Strings can I plug
together?
When using C7 or C9 25-Lamp
Strings,
do not connect more than three strings in a series. You can connect
two C7 or C9 100-Lamp
Strings together
IF you use a 3
Outlet Power Adaptor plug
in between the two light strings. You should never connect 100-Lamp
Strings
together without the 3 Outlet Power Adaptor.
The exception to this rule is our Low
Energy/High Efficiency Lamps in
which case you can run twice as many strings as stated above.
Can I plug a C7 String into a C9 String?
What if they are the same wattage?
No. You cannot mix the two types of strings, even if they are the
same wattage.
Can I connect C7 or C9 bulbs that have different watts?
No. You cannot connect stringers that contain differing watts of C7
or C9 bulbs.
Why are some of my traditional Christmas lights brighter than
others?
Several factors can effect the brightness or look of lamps.
Different watts produce different brightness. Generally the higher
the watts, the brighter the bulb. One exception to that rule is
High-Efficiency/Low Energy Bulbs..
C7 and C9 Christmas Bulbs have either a double dipped or triple
dipped coating of color. The less a lamp is dipped, the brighter
the bulb. Age can also effect the color of a lamp. Lamps that have
weathered a season outdoors usually have lost some of their
protective coating and as a result, they appear brighter than
freshly dipped lamps. To achieve a more consistent look, you may
want to use lamps that are the same age, same wattage, and have been
dipped the same number of times.
Information adapted from Centsible Holiday Lighting at www.centsibleholidaylighting.com
