Saturday, April 23, 2005

Light switches

As part of a remodeling project, I had the opportunity to help tear out the interior walls in a hundred-year-old house. You take a hammer and start by whacking through the plaster. There's about a dozen layers of paint, and then the plaster has hair and all kinds of other stuff mixed in. The plaster was slathered on wooden lath strips. So you strip out all the paint, plaster and lath and throw it in the wheelbarrow.

Once you break through all of that, you find that the walls are insulated with bricks. Yes, bricks. The outside walls are wooden siding, but between the plaster and the siding is a layer of roughly-mortared brick.

The most amazing part, however, was finding the pipes. All kinds of pipes, not for water but for gas. Yes, this house once had gas lighting in all the rooms, and the pipes are still there.

Today we look at all this and laugh. Horsehair??? Lath??? Bricks - for insulation??? Gas pipes??? Using gas for lighting seems amazingly dangerous.

I relate this story to show how easy it is to look at older technology and see the obvious problems with it. Troweling plaster on by hand was time-consuming. Mixing it with horse hair was gross. Insulating with bricks not only took a lot of time, but it did not work particularly well. And lighting with gas presented a host of hazards, from explosions to fires to asphyxiation.

Today's light switches are not quite that bad, but I think that in 20 years people will look at them with the same amusement we reserve for gas lighting.

The most amazing thing about a light switch is that it is totally, completely passive and dumb. What that means is:
  • If you lie down in bed and happen to forget to turn off the light, you have to get up again to flip the switch.

  • If you leave the room and forget to flip the switch, the light stays on regardless.

  • If you turn the light on at night but then the sun comes up 8 hours later and fills the room with sunshine, the light remains on despite the fact that it is no longer needed.
Then there is the fact that the light switch clamps across 14-gauge romex able to carry 15 amps, despite the fact that the light it controls only needs half an amp for an incandescent bulb, and only a tenth of an amp for an LED bulb. The amount of copper wasted in this way is astronomical.

Obviously what you would prefer is an intelligent switch, probably built into the light itself rather than the wall, that can understand your voice as well as the conditions in the room. If you walk into the room at night, the light turns on automatically. If you lie down and say "light off", it turns off. And so on.

The next time you get up out of your chair and walk out of your way to flip the light switch on the wall, think about how primitive a system this is. People will look back at this period in human history with the same quaint feeling that we have when we think about gas lights.

Google

11 Comments:

At 5:38 PM, Anonymous Anonymous said...

This is a pretty interesting article:

Vintages of House Wiring

 
At 12:29 AM, Anonymous Zeb Rice said...

I have an even better idea. You don't even have to worry about turning off the light when leaving the room. Instead of a light switch, a combination infrared detector/voice command system. When the lights are "on", the light bulbs only turn on when a person in the room, and turn off when they leave automatically. To turn it off, just say "lights off". The reason why I suggest infrared detectors instead of motion detectors is that motion detectors tend to turn off if you are doing something still like watching TV or reading, and people are always radiating infrared light.

 
At 7:15 PM, Anonymous Anonymous said...

Marshal, your a man after my own heart. your too witty to obsess over the amazing technology today and be mocked by the robot-controled (kudos on your robot blog, we should warn politicians*) world of tomarro, when they look back and laugh just as we have with our past they'll say "they were so obsessed with there primitive widgets, except that Marshal Brian guy"

*i did a persuasive speech in my 7th grade block class on this, we really should warn politicians and begin taxing big corperations for replacing people with robots

 
At 7:50 PM, Blogger Paul said...

Marshal, your a man after my own heart. your too witty to obsess over the amazing technology today and be mocked by the robot-controled (kudos on your robot blog, we should warn politicians*) world of tomarro, when they look back and laugh just as we have with our past they'll say "they were so obsessed with there primitive widgets, except that Marshal Brian guy"

*i did a persuasive speech in my 7th grade block class on this, we really should warn politicians and begin taxing big corperations for replacing people with robots

 
At 6:46 AM, Anonymous Anonymous said...

I admit it. Now every time I must walk out of my way to flip a light switch it bugs me. How much time do we waste collectively on light switches?

 
At 5:10 PM, Blogger Steve Nelson said...

Why bother with the time and energy consuming process of speech? Have you forgotten "The Clapper?" after all, isn't it much easier to operate and impliment, considering the unit does not have to recognize the multiple and varible commands for "off" that exist in the 3,000-8,000 languages in existance? We already have lights that turn on automatically, outdoor security lights, which never fail to fire themselves up everytime a car or dog passes by. Is this efficiency? Does your dog need to consume 200 watts of power when he walks from your bedroom to the living room and activates every bulb? The point of the switch is control. The switch gives you options. Why should my light turn on when I walk into a room? What if I don't want to disturb someone? What if I like the dark? Furthermore, the wiring in a house is versatile. Certainly you are not suggesting that we wire every bulb and outlet with different gauges of wire. At present, I know I can plug virtually anything into any availible plug, from the 40 watt bulb to the 1,000 watt heater. Think of the added complexity involved power was divided up into availible amperage, different plugs, hell, why not make some plugs DC, some AC 60hz, AC 50hz, 100hz... What if the light in my neighbors house is GE and I have to tell it "off light" instead of my Philips bulb which responds to "light off"? What about a room with multiple lights? Do we program each with it's own adress code, like letters or numbers? And in your neighbors house, how do you know how to adress the table lamp on the right but not the one on the left? For me, the issue boils down to complexity versus convenience, and in this case the complexity outwieghs the convenience.

 
At 7:00 PM, Anonymous Anonymous said...

Excellent article. It is said by some that someday, every physical object will contain intelligence and have an IP address (it will probably require IPv6).

Today, the solution is rather complicated. But it works at my house. I use X10 enabled light switches. I have several ways to turn on and off lights...

- Manually flip the switch (they're momentary switches)

- Use a remote control (IR to an X10 IR receiver, also controls the curtains, TV, Stereo, DVD player, etc.)

- Use the simple X10 mini-controllers next to my bed, in the living room, etc. These controllers simply plug into any outlet and let you control lighting and other appliances with the push of a button… I own two of these. You can move them to any outlet in the house.

- Since I have a computer controlled X10 home automation system, I have computer control over my lights… some turn on and off based on time of day, day of week, and holiday schedules. Others, because I know where in the world I am, follow sun rise and sun set times (sun set time +30 minutes, or sun rise time -45 minutes).

- Motion sensors (again, X10 based) turn some lights on automatically, and I’ve programmed some with additional instructions. For example, if its between midnight and 5:00 AM and I walk into the bathroom, bring the lights to 1/2 normal brightness over 30 seconds.

- Finally, I have voice command over the light switches (“computer, master bedroom lights off”).

Surprisingly, my system is very reliable.

Downsides include the expense of the system. You can pickup a good, old fashion light switch for about $1.00 at Home Depot or Lowes… expect to pay between $22.00 and $50.00 for an X10 enable switch. Typically, additional X10 signal enhancement equipment is required (phase couplers, signal boosters, filters, etc.) all of which are as easy to use as plugging into the appropriate outlet, but they can be expensive. Finally, for scheduling and customization, you need a PC running 7x24 with home automation software (good software runs about $150.00 to $200.00 to start).

Finally, the big stumbling block for a lot of people is the customization you’re required to do (voice training, setting up rules and schedules, security, etc.).

Its not there yet, but I can see the light switch as we know it going away... mine already has.

 
At 10:10 PM, Anonymous Anonymous said...

'Smart' homes not far away

 
At 8:57 AM, Blogger tweedledeetweedledum said...

This blog is awesome! If you get a chance you may want to visit this security software site, it's pretty awesome too!

 
At 7:07 PM, Anonymous back_ache said...

One word "zigbee"

 
At 11:37 PM, Blogger Learn Chinese language on hanbridgemandarin said...

All Hanbridge instructors are accredited language teachers, native speakers of Mandarin, and have obtained a Bachelor's or Master's Degree. in language. All have standard Mandarin pronunciation and have completed Hanbridge's rigorous training program.Most importantly, they are committed to and enthusiastic about teaching and have a passion to help people learn to speak Mandarin and learn about Chinese culture.



More Chinese learning tags : Chinese language class | learn mandarin online | learning Chinese online

 

Post a Comment

<< Home