The JimOnLight Guide to Christmas Lights, Parts 1 to 5

It’s that time of year again, albeit maybe a little early…  there are lots of Canadians who are already rocking the Christmas lights, and by rocking I do mean there are lots of strands of LED Christmas lights all over the place in Toronto.

This is why it’s ABOUT TIME to publish the JimOnLight Guide to Christmas Lights again, by popular demand!!!


Part One is geared towards sharing where Christmas Lighting got its start, including going WAY back to talk a bit about what actually happens in the sky around Christmas time (or Kwanzaa, Hanukkah, Flying Spaghetti Monster time, or whatever flavor of religion you pick for the Holidays)and how we’ve been dealing with it for a few thousand years.


Part Two takes some of the most basic information about Christmas lighting — the light sources— and breaks them down for the reader to make it easy to understand and identify different kinds of Christmas Lights.  You know, for that moment when you have to pull the ball of lights out of the box in the garage and actually NOT burn your house down.


Rain lights, curtain strands, cascades, and all kinds of other terms that mean something about the different arrays that Christmas lighting come in — Part Three of the’s Guide to Christmas Lighting is all about telling those arrays apart so you can get back inside and drink some Wassail!


This is an important one — Part Four talks about how NOT to get yourself dead while doing all of that Christmas light installation!


…not last, not least, and definitely not the end of the series, but perhaps one of my favorites!  A quick overview of some of the basic and important electrical equations that can help you make a little more sense out of the task of hanging Holiday Illumination!

Ok world, let’s be safe and sound out there, and I would say let’s not be tacky, but we all know that it will never ever happen at Christmas time!’s Guide to Christmas Lights, Part Five: Christmas Lighting MATH!

Christmas Lighting MATH

It’s that time of year again – time for hanging those crazy little mini incandescents, C-6’s, and LED strands that you’ve added in (because they’re the “newest, brightest colors” [!!!]), and you’re digging out the cube taps and power strips.  You’re looking through drawers and cabinets for the little bags of spare lamps, fuses, and blinker lamps that you’ve stashed all year, or from last year.  Yeah, we know the drill.

Have you ever noticed that many of the packages of Christmas lights that you buy say things like “do not plug more than X strands together at once,” where X is a number like 3 or 5, depending on several factors like lamp size and wire length?  Well, surprise, there is a good, solid reason for that!  Generally, that bit of instructions and the numbers associated with them has something to do with preventing you from burning your house down and killing you and your whole family while you sleep.  I mean, generally.  But who really reads those directions, right?

If you are smart and you like your family and house and nice stuff, I would advise following those directions.  First, let me show you, for example, how fast a Christmas tree turns a house into carbon rubble when it catches on fire from, for example, an electric short:

Pretty crazy, huh?  That’s why we follow directions.  The days of a stack of Edison plugs stuck together in an outlet that’s way overloaded need to be gone.  Be smart, and you’ll not have to worry about these kinds of scenarios.

Unfortunately I have to put the disclaimer in here that the information below is to be used at your own risk – will not be held responsible if you cause damage or death.  If you’re not a qualified electrician and have questions about something that a qualified electrician should be doing, don’t do it.

When trying to figure out how many strands of christmas lights to stick end to end together, it’s best to just follow the directions on the package.  Remember just a minute ago when I said “Generally, that bit of instructions and the numbers associated with them has something to do with preventing you from burning your house down and killing you and your whole family while you sleep” ?  This is the part of the story where that actually shows you that it’s easier to follow the directions than it is to burn your whole house down.  However, let’s just say you have limited information, or small combinations of variables like individual lamp voltage, individual lamp amperage, total strand wattage, or for some reason, wire gauge of the strand.  You can manipulate the good old Power Formula to give you the answers using some constants that you can kind of take for granted.  You know the power formula, right?  The “West Virginia Formula?”

Here are some things you can pretty much use at your own risk as constant numbers to help with the figurin’ of the math, when it comes up:

  • In the USA, which is where I live, the voltage at the wall outlet is gonna be somewhere between 110-120 volts.  For a constant standard number, you can use 120 volts as the line voltage at the wall when you’re calculating, it’s the upper limit.
  • Typically in your home, the wall outlets and circuits therein are going to be rated at either 15 amps or 20 amps.  The best way to figure out which each one is would be to go find that outlet in the breaker box and verify the circuit’s amperage rating on the breaker itself.  I just went and checked the breaker box here in my apartment, and all of the circuits in my place are 15 amp circuits.  I’m guessing that a lot of your homes are going to be on 15 amp breakers.
  • A large majority of christmas light strands are wired with 22 gauge (awg) wiring, which has a total ampacity rating of about 5 amps.  A strand of 150 incandescent mini lamps at 36 watts total is only pulling 0.3 amps.
  • If you can verify that all wiring from the load to the breaker is the proper gauge for maximum wattage use for a 20 amp circuit, that circuit will provide a maximum of 2400 watts.  The same circuit on a 15 amp breaker will give a maximum wattage of 1800 watts.  Please note – this is if all conditions, like all sections of wiring and multi-gang units, like power strips and cube taps.
  • For a reason that I have yet to figure out, light strands are calculated on this odd “minus two per fifty lamps” constant.  What I mean by that is the calculations on the entire strand of lights seem to be calculated by taking away 2 lamps per every 50.  For example, if you calculate all of the variables of your typical string of 150, you get numbers that are for 50 lamps, but the actual ratings are for 144 lamps, which is 6 less than 150, or 2 per every 50 lamps.  Weird, huh?

Let’s put some of this information to the test and figure out a challenge.  I just found a 150-lamp string of mini-incandescents.  I want to know how many amps this string will pull as a whole.  There are some things we know, but we don’t know amps.  Let’s manipulate that good ol’ Power Formula:

Easy, yeah?

Okay, here’s another one:
How many strands can I plug end to end, knowing that A) the wire on the strand of lights is probably 22 gauge, B) each strand of 150 draws about 0.3 amps, C) the 22 gauge wire in the strand is rated for about 5 amps, and D) there is a 3 amp fuse in line on each strand of 150 lights.  I plan to plug the business end of these into the wall, rated at 15 amps.

Well, I checked the package, and the package said not to plug more than five strands together, for a total of no more than 210 watts.

Technically, if I multiply the 36 watt strands together in total, so five total strands, that equals 180 watts.  A 6th strand added would give me 216 watts.  216 watts, which draws 1.8 amps, is well under the 3 amp fuse rating.  So what’s the right answer?

The right answer is what the package said, in this case.  The package said no more than five strands end to end.  Sure, you could plug together that extra strand, because even with adding that sixth strand, the total amperage is only 1.8 amps, which is still 1.2 amps under the 3 amp fuse rating.  However, when something goes wrong and you burn down your house, your neighbor’s house, and your other neighbor’s house, what is going to happen when you get sued is that the fire inspector is going to somehow find that sixth strand plugged in, and the box told you that you were only supposed to plug five strands together.

See how this works?  This is purely legal.  When you go outside of the package’s advisory, you thereby null and void any warranty, even though technically the product could handle it.  It’s a slippery slope.  You have to be careful.

Okay, here’s another one:
Let’s say I have a 12 gauge heavy duty extension cable to which I will plug a 15 amp power strip with a circuit breaker.  How many strands of christmas lights can I plug into that power strip and still be okay, technically speaking?

We know a few things here – the 12 gauge heavy duty cable is rated at 20 amps.  However, our power strip is only rated for 15 amps, so that brings our total load down to 15 amps.  The weakest rating in the group is where to place your limit.  So if you were to be completely ridiculous and stupid and plug another extension cable between that power strip and the heavy duty extension cable that was, say, a 16 gauge cable (rated at 13 amps), then the system is knocked down to 13 amps.  Epic fail can happen really quickly here, so pay attention to what you’re doing.

Since we can’t plug more than five strands end to end, we can use the power strip to plug in several sets of five as groups of five.  Make sense?  My power strip is rated for 15 amps, so I need to figure out if I can plug a strand of five strands into each of the six female outlets on the power strip.  Math time!

Let’s go a step further – how many of these power strips with six strings of five strands of christmas lights can we plug into the wall in one 2-gang outlet?

This really depends on the load rating on the specific circuit you’re plugging your christmas lights into, as well as how many other branch circuits are connected to that specific circuit breaker.  What I mean is that sometimes several outlets in your home or garage can be running to one circuit breaker.  That sucks, sure, but it happens, and it happens a lot.  My condo, for example, has a total of 12 2-gang Edison outlets on the walls, and a total of five circuit breakers controlling them all.  One of the circuit breakers in my condo has four branch circuits – on a 15 amp circuit breaker.  That means that over four 2-gang outlets in my apartment I can only plug a total of 15 amps’ worth of devices.  That kinda sucks.

You need to be able to know the rating of your circuit breaker in order to be able to answer the question above.  Go open your circuit breaker panel or fuse box and check what the rating is on the circuit you plan to use.  Check out these images below – a 15 amp and 20 amp breaker, and a 15 amp and 20 amp screw-type fuse:

Breakers – notice the rating number painted on the actual switch itself:

Fuses – again, notice the rating number (15 and 20, for 15 amp and 20 amp):

Remember from above, a 15 amp breaker or fuse is only rated for 1800 watts, and a 20 amp breaker or fuse is rated for 2400 watts.  So could I plug in two of my power strip rigs into a 15 amp breaker or fuse?

The answer is no, no you cannot.  Each of the power strips has six strands of five strings of lights end to end, for a total wattage of 1080 watts, drawing 9 amps.  Two of them into one circuit that had nothing else plugged into it totals 2160 watts at 18 amps, which is definitely too much for a 15 amp circuit breaker or fuse.  However, if the circuit was a 20 amp rated circuit, 2160 watts at 18 amps (or two of the power strips with six strands of five strings of lights at 9 amps each) would be close to the limit, but acceptable.  The biggest thing that people forget to check is the existing loads on a branched circuit – like a fridge, appliance, radio, or what-have-you, that pushes the circuit to the point of tripping the protection (breaker or fuse).

I need to tell you all – if you have aluminum wiring in your house, none of this stuff applies to you, as aluminum wiring is dangerous and scary. Call an electrician to have that replaced.

Generally, some good rules and practices to abide by when doing electricity math with christmas lights:

  • if there are instructions on the packaging relating to how many strands you can plug in end to end, follow it.
  • if you plug something in and it trips a breaker or blows a fuse, something is wrong – fix it before proceeding.
  • never overload a circuit, ever.
  • if you don’t know the answer, get in touch with a qualified professional who can help you figure the answer.

Be safe out there, folks!  Safety first, they’re just christmas lights after all!

day 33: starry night

Thanks, Elcosh Images, Aubuchon Hardware, Fuel FixHome Depot, and Power Stream!

A Downtown View of Oklahoma City, Lit for the Holidays

Living in a condo tower downtown has its privvies, I guess.   I’m not really much of a downtown dweller, at least lately, but I seem to leave home and return home these days when the sun is still a snooze slap away from waking up.

I certainly take a lot of pictures of the downtown nightscape – my apartment is right next to the Oklahoma City Murrah Building Memorial, and it faces the downtown skyline.  Parts of Oklahoma City are bustling with holiday-themed lighting, and I’m planning a series of photos of the city at night.

Here’s the first installment of architectural lighting from Oklahoma City, OK – this set from the 13th floor of my tower – for reference, here’s the city skyline in August:

…and here’s a detail of the Chase Bank building (and I don’t know the tower to the right yet):

Wider city shot – It’s true – apparently crosses cover the idea of “Holiday” in general here in Oklahoma…

Here’s looking the other way at Oklahoma City, looking southwest:

More shots – click on any one in this gallery, and a Gallery View will open up for your enjoyment!

Death Metal Christmas Lighting! AAAAAAA!

From the Daily What comes this crazy Death Metal Christmas lighting video – the music is Slayer’s “Raining Blood.”

I mean, of course it is, come on.  This just goes to show you that Christmas lights add pizazz to songs other than Trans-Siberian Orchestra and Mannheim Steamroller, I guess.’s Guide to Christmas Lights is BACK!

Oh yes, it is THAT TIME AGAIN, my friends!

It’s time for the Guide to Christmas Lights! This is the time of year when people dig out the crazy plastic Santas with sled and reindeer, the Frosty the Snowman yard art, and go to town getting all Clark W. Griswold all over their houses!

The Guide to Christmas Lights has been blessed with some pretty worldwide attention, having been read in 190 countries across the world.  We even got plagiarized by Gizmodo last year!  How crazy is THAT?!

I’ll be adding more parts this season – coming on Tuesday, November 30, I’ll post Part Five – Christmas Lighting MATH!  Until then, you can get caught up on the first four parts:

PART ONE:  The History of Christmas Lights

PART TWO:  Modern Christmas Light Lamp Types and Sizes

PART THREE:  Form Factors of Christmas Lights

PART FOUR:  Christmas Light Power and Safety

Stay tuned – more Guide to Christmas Lights parts coming up!

Siemens Superstar – A Wind Turbine-Sized LED Display

Super company Siemens (they’re the parent company of OSRAM) installed a ton of high-power LED modules onto a wind turbine located next to the A9 Autobahn highway at Christmas time.  In conjunction with multimedia artist Michael Pendry, Siemens installed 9,000 OSRAM LEDs onto the blades of the wind turbine.  You could see the installation (it was 70 meters wide, or almost 230 feet) from almost 20 miles away.  All of the display was powered by the wind turbine, which is extra awesome.

The installation was up for the Global Climate Conference in Munich, and stayed up until January 6, 2010.  You have to see the video and images I posted below.  At the very bottom, I posted the press release.  Check it out!

Images from the Siemens Press Site:

The press release from Siemens:

Quite a few people wondered if it would ever function. Yet right on time for the first Advent Sunday it is obvious to all: But still it moves! Siemens — together with multimedia artist Michael Pendry — has lighted up the world’s biggest revolving Christmas star. The lighting installation can be seen throughout December at the northern gateway to Munich — beginning at dusk every evening. “The Siemens Superstar is a pioneering technological project and an important symbol for the Global Climate Conference in Copenhagen. Green innovations are lighting our way to a better future,” said Siemens President and CEO Peter Löscher. “Munich has a new landmark for the Christmas season. It stands for renewable energies and energy efficiency — and these are also important issues for Munich. By 2025, we want Munich to be the world’s first city to meet all its energy requirements from renewable sources,” noted Munich’s Mayor Christian Ude enthusiastically. “I like to take art outside the narrow confines of museums,” explained lighting artist Michael Pendry.

Siemens developed and completed the unique and pioneering technological project together with Munich multimedia artist Michael Pendry over the past twelve months. The lighting installation consists of 9,000 Siemens Osram light-emitting diodes (LEDs) that are as bright as around 20,000 Christmas candles. Yet the entire installation uses only as much electricity as a hair dryer or a water kettle. In good weather, the art object can be seen for 30 kilometers. The span of the world’s biggest revolving Christmas star is nearly 70 meters — as wide as a soccer field.

Nearly 400 meters of power cables were laid for installation — a length that would reach over the top of the Eifel Tower. The lighting installation adds 100 kilos to each rotor blade. The LEDs are fastened to the wind turbine blades with superglue used in space, since under windy conditions the LEDs are subject to forces up to 20 G, or more than three times the g-force experienced by an astronaut during a rocket launch. Just a few days ago, TÃœV SÃœD — the technical service corporation responsible for inspecting and testing technical installations — gave its final approval to the installation. Munich residents, motorists and airplane passengers can be assured everything is in order.

Because of the wind turbine’s prominent location next to the A9 autobahn — a main traffic artery not far from the airport and used by well over 150,000 motorists a day — it was considered to be ideal for the lighting installation from the very beginning. In the fall of 2008, representatives of Siemens and Munich multimedia artist first discussed the idea of creating a shining symbol for green technologies and sustainability on the eve of the Global Climate Conference in Copenhagen. And what better place to demonstrate the sustainable use of electricity than a wind turbine? The operator of the wind turbine, Stadtwerke München (Munich City Utilities), offered its full support for the project from the very beginning.

In the following months, the idea slowly became reality. At first, the focus was on the project’s technical feasibility. In the spring of 2009, a handful of experts in various disciplines such as wind energy, aerodynamics, lighting and adhesives got together to sketch out all aspects necessary for realizing the project. Answers had to be found for all key issues: How should the LEDs be arranged to have the least possible impact on the wind turbine’s aerodynamics? Which type of LED should be used? Which adhesives were most effective for securing the LEDs in every type of weather?

Late in the summer, the wind energy experts completed their computer simulation analyses on the effects of the installation on the rotor aerodynamics. At this point, tests were begun under real conditions: In wind tunnel tests at the Technical University Berlin, over 15 different configurations of LED models, lighting arrangements and cable routing were analyzed until optimal conditions were found. Tests showed that the LED installation had only a minimal effect on the wind turbine’s performance.

Yet even after the wind tunnel tests were completed late in the summer, all hurdles still hadn’t been taken. Approval from all relevant authorities had to be obtained. And last but not least, the lighting installation had to be attached in only two weeks. 30 technicians worked day and night to make the Siemens Superstar shine. Programming the lighting animation alone took two full days. The lights are coordinated in real time with the various strengths of the wind and speed of the wind turbine itself. A technical masterpiece!

Truly excellent.




I was unable to get home to see my parents this year for Christmas, so I hope you are all having a great Christmas Day with your families and significant others.  Take this day to just…  breathe.

To all my new friends from my experience in Sweden – thank you all for the opportunity to see beauty and intelligence from parts of the world I have never visited.  To my friends in Iran – keep your head up, we believe in you.  To my US Marine, US Army, US Navy, and US Air Force friends sitting in Afghanistan and Iraq this Christmas, we’re all thinking of you, be careful, and we can’t wait to see you when you get home!

Merry Christmas, world!

A cool dude, Brad Peterson, sent me a few links to some awesome Christmas lighting videos – thanks Brad, and check this stuff out!  Go to High Voltage Productions to see these videos – but first, get some PIE!

(and don’t forget the Cool Hhwip)

Christmas Lights in Perth, Australia

Christmas lighting is still in fashion, at least until the New Year, right?  We always took ours down sometime after the first of January, so take that as a hint, all of you “leave them up until April” people!

I saw an interesting post on CNN’s iReport site about a family in Perth (Australia) that has a massive Christmas lighting display – they also made a bunch of bread on it that they donated to a local children’s hospital.  This Christmas light display raised $22,000+ last year!  They’re shooting for $30,000 this year. (ps: I would have embedded the CNN video, except there was no way to turn off the autoplay feature – which would have annoyed you all. Cnn, don’t you want people to embed your videos?)

The creator is a guy named Kym Illman, the CEO of a company called Messages On Hold.  This beast is 176 channels of control, over 6 kilometers of cable, and 50,000 LEDs.  Watch this video of Kym Illman on Perth’s “Today” show:

Here is their display video – can you believe how much stuff is in that rig?!

Thanks, MoH!

Gifts? For a Lighting Professional?! Oh my.

Yeah, oh my indeed.  I think one of the hardest things to do is to buy gifts for people working in the lighting industry.  I mean, it’s like anything technical, really – if it isn’t related to gaming, clothing, or nerdiness, then it’s something like a $16,000 spectroscope or a $3,000 dollar oscilloscope.

What?  Who asks for that for christmas?  Can Santa’s elves make that?  Do they just contract that out or something?

The other hardest thing about buying presents for a lighting professional is when you forget to get them until the Monday before Christmas!! I went through Amazon this morning and grabbed some stuff that I think lighting people would like, and I listed some of it below.  I picked stuff that I thought I would like to either give or receive – so good luck, and hurry up!  Christmas is on Friday! AAAA!  Two day shipping!
Gift ideas for lighting professionals

Did you pick something out?  Time’s a wasting!

  1. 10-LED USB light bar
  2. Kensington “Flylight” USB light
  3. Black and Decker “Ready Wrench”
  4. Crescent brand adjustable spanner with thumb slide (I have 2 of these!)
  5. 8″ Stanley brand “crescent” wrench (adjustable spanner)
  6. Cooper Lighting 80-LED rechargeable folding worklight
  7. Amprobe LM631A digital light meter
  8. Gerber Pro Scout needle-nose multitool
  9. christmas ornament earrings!
  10. christmas light earrings!
  11. Gerber’s Legen multitool
  12. Victorian-era Edison replica lamp, 25W
  13. 1890 Edison lamp replica, 40W
  14. 1910 squirrelcage filament replica lamp, 40W
  15. 1920 double-looped filament replica lamp, 30W
  16. 28-piece Klein tools Electrician set
  17. Leatherman New Wave multitool with leather sheath
  18. Lava Lamps!
  19. USB charm light
  20. christmas lights necklace
  21. Mastech 20-200,000 lux meter
  22. Sekonic L-358 Flash Master
  23. Sekonic L-398 light meter

Guitar Hero Christmas Lights Creator Speaks with!


After posting the article about Guitar Hero christmas lighting this morning, I was able to get ahold of the display’s designer to ask him some questions about how and what he did to have such a great display.  The designer’s name is Ric, and he was gracious enough to answer some questions I had about his work and his background.  I hope everyone enjoys the little interview I was able to get with Ric about his rig and his process.  Check it out!  Also check out the Light-O-Rama site for the control stuff mentioned in the article – very cool!

JimOnLight: Do you have a background in lighting? Your display and control is impressive – I am curious as to if you’re a professional or a hobbyist with some skill!

Ric: I’ve done some lighting, but most of my background is in media production and theatrical style illusions. The Christmas Light show is really more of a media presentation with lots of light edits in time with the music, made like a music video.

JimOnLight: How did you come about the idea of having such a large christmas light rig? Was there a muse or inspiration of some sort that led you to put it together?

Ric: I’ve always loved doing Holiday light displays, and years ago I experimented with simple sequencers. Eventually I was able to put together my first show using MIDI controlled dimmers and programmed it in Garage Band on a Mac laptop. The year after that I discovered Light-o-Rama kits and started building them. Each year more controllers get built and the shows get more elaborate.

JimOnLight: What types of lighting you use for your display? I assume that there are a mix of LED and incandescent lamps – can you give me some insight into your mix?

Ric: I’m starting to use LEDs more and more. I love the single color strings that punch through everything with dichroic style – single frequency light. Especially the blue and violet. LEDs switch on and off instantly allowing stunning music sync. I still have a lot of incandescent lights for the big white moments. I’m not happy with the white LEDs yet, the color temperatures are all over the map, even within a single string. There is a warmth to the white incancesdents that still can’t be matched with LEDs.

JimOnLight: Please tell me about your control system – we would love to have some insight! Are you using some kind of timecode (MIDI, SMPTE), or do you have something proprietary that you’ve created?

Ric: I started with MIDI, but quickly got frustrated with the limitations. Light-o-Rama controllers offer amazingly cheap cost per channel. I usually buy 16 channel kits for around $100. I experimented with some bank switching circuits to allow one board to control separate sets of lights, but that turned out to be more trouble than it was worth. To do the 09 xmas show I added three new controllers for a total of 7. LOR software is quite good, and has been able to handle everything I have come up with.

JimOnLight: Do you provide a way for your neighbors and passersby to listen to your inspiration music to your display?

Ric: The audio plays at a low level until around 9:00 for pedestrians. Any time the show is running, the audio is broadcast on a low power FM transmitter so people can listen in their cars as loud as they like.

JimOnLight: Something that everyone probably wants to know – how are your electricity bills?

Ric: Not bad at all! Compared to the last year we had a static display, the shows use about 75% less energy, mainly due to the fact that in a show any given light is off much more than it is on. Now with all the LEDs, power use is down even more.

Ric, thank you so much for your time!  Everyone should check out Ric’s youtube channel (he’s kumbaric on youtube) – he’s got videos galore and lots of skill!  Enjoy!