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What is a Touch Lamp?

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  • Written By: R. Kayne
  • Edited By: O. Wallace
  • Last Modified Date: 01 October 2014
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A touch lamp is a lamp that can be activated by simply touching the lamp, rather than flipping a switch. Touch lamps are commonly used as nightstand lamps because it is so easy to turn them on in the dark. Typically the entire lamp is touch-sensitive, including base, neck and lampshade, all of which are metallic.

A further advantage of a touch lamp is that it can turn a standard light bulb into a three-way bulb. Tapping the lamp once will cause the bulb to glow at 33% of its rated capacity; tapping it twice brings it to 66%; and a third tap results in full wattage. A 60-watt bulb, for example, can be used as a 20-watt, 40-watt and 60-watt three-way bulb. In this way the touch lamp provides handy low-light conditions for eyes that have adjusted to the dark, while offering brighter conditions for reading or dressing, all from a standard light bulb.

The design of the touch lamp is another plus, making it durable and reliable. External switches on traditional lamps can become dirty over time, filling with dust, sloughed off skin cells and oils. A gummed up switch can eventually render a lamp useless, or at the least, make it unpredictable. Touch lamps, free from external switches and barring physical damage, continue to operate like new for the duration of their lives.

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As to potential disadvantages, a touch lamp might not be ideal where it is likely to be prodded, pushed, handled, or inadvertently contacted often, such as next to a computer or on a desk, as it can be annoying to have to “tap it off” each time. A passing pet cat can also activate the lamp, wasting electricity. One way to avoid the latter situation is to use a power strip with an on/off toggle switch, and toggle off power before leaving home. Unplugging the lamp also works but is more trouble.

A touch lamp operates on the principle of capacitance. Capacitance refers to the capacity of an object to hold electrons, or an electrical charge. Alternating current (A/C) switches inside the lamp are affected by touch because a person's body is made mostly of water and is therefore a fair conductor of electricity. When you touch the lamp an oscillator responds to the change in charge and this activates the switches to toggle the light on or off.

Touch lamps are available at reasonable prices, starting at under $20 US Dollars (USD) and are available everywhere lighting fixtures are sold. Department stores and home improvement depots also sell touch lamps.

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anon233035
Post 6

We have a touch lamp on bed side tables on each side of our bed. There is also a clock radio on each side. These lamps have worked fantastically for several years. Recently one of the lamps turned itself on almost every day. We have no pets and we are seldom in the bedroom during the day. This has never happened at night. Any ideas what could be causing this problem?

anon58062
Post 5

I am interested to know whether these switches consume any power when the light is turned off. i.e. is some power consumed in standby mode?

I would like to use this switch in a solar lighting system I am developing, but it would be essential that zero power be consumed in standby mode.

Can anyone advise on this?

anon24861
Post 4

Did you try unplugging it, waiting, then plugging it back in?

awsummers
Post 3

I have a touch lamp that my children gave me about 13 or 14 years ago. A couple of nights ago the light bulb had burned out so I replaced it with a regular 60 watt bulb like the one that had been in it for a long time. When I put the new bulb in, the lamp came on immediately as I screwed the new bulb in. Now I cannot get the lamp to go off. Can you tell me what the problem might be. The lamp is kind of special since my children gave it to me and I really hate to have to replace it. It has really been a good lamp. I have probably only had to replace the bulb once or twice before in all the years that I have had the lamp. Thanks for any help or suggestions that you may have.

tubesareking
Post 2

Touch lamps are convenient, but there are safety concerns, they create tons of electrical interference and they are prone to false triggers.

1. safety - its rare, but the module can overheat. I haven't heard of any fires resulting, but burning smells have been reported. In addition, if a power surge damages the safety X/Y capacitors in the circuit, an electric shock is possible.

2. interference - to radio, TV etc. I've seen what a touch lamp can do to the picture on a 46 inch plasma TV and folks, it ain't pretty!

3. false triggers - you come home after a hard day's work and find the light on - but you were sure you turned it off. Or worse - you are awakened in the night by the bedside lamp coming on.

The solution? Get a good powerbar or power strip - one that has surge protection at least 600 joules, more is better [to protect those safety capacitors!] and EMI RFI filtering [at least 50 db, 70 is better] to keep the oscillator generated interference off the powerline and to keep RF signals from getting in to the lamp through the powerline and causing false triggers. Good names to look for: APC, Belkin, Tripp Lite [the high end ones are very good], Monster [good but pricey]. Metal cased units are better than plastic as a general rule but are hard to come by. The main thing is look for surge protection expressed in joules and EMI/RFI expressed in db.

Oh, and that plasma or LCD TV? Get a really good powerbar for it too - same rules - lots of joules and lots of EMI/RFI filtration too.

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