The Computer Corner, February 23, 2007
By Charles Miller

Warts and all

This week a few thoughts about something a lot of us love to hate. I loathe these devices so much that I have a big box full of them. I must have 50 different sizes and kinds in the box, just in case I need one.

They are “wall warts” or “socket warts” or “soap-on-a-rope” transformers: small power transformers with an integrated plug designed to plug directly into a wall outlet. The term “wart” is a well deserved pejorative, because the darn things always block off one or two more electrical outlets than they use.

These are used as power sources for all kinds of small electronic devices that would become too bulky or hot if they had the power transformers inside them. That has always been the company line, but the truth probably has something to do with the cost of obtaining Underwriters Laboratories certification.

Wall warts are also called “energy vampires,” because when they are plugged into the wall they continue to consume power even when they are not in use. Touch one and you will feel it is slightly warm. We know that we should always unplug our laptop computers, cell phones or iPods at the wall, but we don’t.

Sources say these wall warts eat up about 4 percent of the electricity used in the average home. If this is true, in the US this extrapolates to over 50 billion kilowatt-hours, or all the energy produced by 20 power plants.

George W. Bush considered this to be enough of an issue that in July 2001 he gave a speech promising an executive order to deal with it. Since then, he seems to have been busy with other issues.

I have my own set of issues with the darn things and the way manufacturers use them. As I mentioned earlier, most manufacturers use wall warts to circumvent the cost of certifying their product with Underwriters Laboratories. If they can use a UL-approved wall wart, then they do not have to submit their product to the UL certification process.

It is extremely important to keep the correct wall wart with the device with which it is intended to be used. I have two identical SMC model SMC7004ABR Ethernet routers. One day I unplugged everything to dust and, when I plugged one of them back in, it went “poof” and stopped working. I just shrugged my shoulders, knowing that computer electronics do fail like that. A few days later, the other router went “poof.”

When I examined the two failed units I noted that though they were identical model numbers with identically sized power sockets, one said 5V 2.4A and the other 12V 1A. I was dumbstruck to suddenly realize why both units had burned out and that I had done it. Twelve volts burned up the 5V circuit immediately, and powering the 12V router with only five volts eventually burned it out.

That SMC used two different voltages for the same model number product is dumb. Using the same size plugs and sockets on two such different voltages was really stupid of them.

I would have called the manufacturer to vent my frustration, but they would have just told me to pay attention to the labels next time. Since then, I have been meticulous about checking the voltage and amperage of each socket wart before I plug it in. 

I have two US$50 paperweights, model SMC7004ABR, to remind me.

Charles Miller is a freelance computer consultant, a frequent visitor to San Miguel since 1981 and now practically a full-time resident. He may be contacted at 044-415-101-8528 or email FAQ@SMAguru.com.