THE BLEEDING EDGE Technology Versus Dirty Power D Dave McClure
Mr. McClure is a consultant and widely published writer on technology issues. He can be contacted at dave.mcclure@ cpapracticeadvisor.com
igital devices have always had a love-hate relationship with the power needed to operate them. In addition to low battery life and power failures, there is the insidious "power spike" that seemingly can be caused by anything from a passing storm to a cat rubbing up against your leg. A tiny whisp of white smoke you don't even see, and the device is gone forever.
And then there is the whole issue
of "Dirty Power." The power in your house or office
is delivered by the power company to your electrical outlets at a stan- dard 125-volts. Plus or minus, that is, ten percent. So the actual power delivered to a device could be as little as 112.5 volts, or as much as 137.5 volts. Which may be all fine and good for a hair dryer, but plays with your computers and printers. That is one of the reasons that very sensitive devices like laptops and tablets run off of DC rather than AC power, so that the battery acts as a kind of power filter. Kind of. Not bullet-proof.
Still, most computing equipment
today comes with a power supply that is built to handle the every-day problems of dirty power and routine fluctuations from low to high. What they are not equipped to handle is the random lightning strike on the power pole outside your house, or when your ancient refrigerator in the kitchen and the old freezer in the garage decide to kick on their compressors at the same instant. And it isn't just your computer
that you have to worry about any more. Those big-screen televi- sion sets with the fancy high-def cables that are gold plated for a per- fect signal? Even a power surge that does nothing else can take out the HDMI circuits, leaving you with a problem that costs more to fix than the TV did in the first place. Cell-phones? These are sometimes known as "fry-babies." USB devices like printers? The printer is fine…but the USB port is fried. So how do you provide protec-
tion for a small office or home? The question is more complicated than
you might expect. r Forget power strips. This is the worst form of false confidence, even with the big units costing a hundred dollars or more. They simply don't work. Or if they do, they work only for a small number
20 August 2012 t www.CPAPracticeAdvisor.com