20 Feb. 2007
SETI League
PriUPS Project


I've been remiss.  I should have RIKL-Reviewed this gadget many months ago.  Everybody needs one.  Let me illustrate:

I've been noticing a problem recently.  I've been chilly at night, despite my judicious use of a "warming blanket," and I finally realized why.  The blanket went defective in such a subtle fashion that I ascribed my night-time lack of warmth to the almost zero-degree (F) temperatures outside.  I finally decided that it must be something else after I substituted a different blanket and immediately became my usual toasty self.  Of course I intended to return the defective blanket for "repair or replacement."  In the process of doing so, I had to call the Sunbeam organization for return instructions, and had speaks with their customer service. 

If you've spent any time on this web site, you might well agree that I have a reasonable grasp of knowledge electric, and might well be able to diagnose a defective "warming blanket" as such.  When I called to return the blanket under warranty, the woman on the phone would not take my word for it.  Before she would issue an RMA, I was told that I must "reset the blanket."

Resetting The Blanket

Here is how you reset a Sunbeam warming blanket:

  • Unplug the controller from the wall

  • Unplug the controller from the blanket

  • Plug the controller into the blanket

  • Plug the controller into the wall

  • Unplug the controller from the wall

  • Unplug the controller from the blanket

  • Plug the controller into the blanket

  • Plug the controller into the wall

Presto!  The blanket is now reset.  Aren't you glad I shared this information?  After resetting the blanket, I told the customer service woman that it still wasn't working.  She issued an RMA, and the blanket is on its way home to Mississippi.  I should see it again in "two to three weeks."

How Did I Know It Wasn't Working?

I lulled you into a sense of security with the Litany of the Reset Ceremony and you didn't catch this:  In fact, when I was done, if I didn't have my trusty KILL A WATTTM I would have had to put Ms. Customer Service on hold while I crawled into bed and waited for the warming blanket to not get warm.  As you can imagine, this might have taken a while.  But with the KILL A WATT I could see that the blanket wasn't drawing power, a sufficient condition for it to immediately not get warm.  I told her as much and got my RMA without further argument.  Bonus! The KILL A WATT is good for other things, too!

KILL A WATT - complete unit

What is the KILL A WATT?

It's a small, cheap appliance that plugs into any grounded (3-prong) 115VAC (nominal) electrical outlet.  It will measure the voltage and frequency at the outlet all by itself, which provides assurance that your voltage is OK and your electric clock won't run wild.  But that's just the start.  Once you have plugged it in, you can then plug something into it.  (Think of it as a very short extension cord if you wish.)  The fun begins when you turn on whatever is plugged into it.  It will tell you how much power your item is taking!  Thus, when I cranked up the substitute electric blanketKILL A WATT readout 228 Watts I could immediately see that it was absorbing 228 watts from the AC line.  This amount of power will definitely make you toasty on the coldest night, by the way!  The average power is much lower unless you put the blanket on the highest setting.   Unless you're as compulsive as I am, you probably won't be measuring the power requirement of every household item.  But it's nice to know that you can.  It's also great fun to see just how much power simple substitutions can save, such as replacing an incandescent lamp with a compact fluorescent.  And you can use it to see just how much power your "instant on" teevee uses when "off."  

One avowed purpose of the KILL A WATT is to save energy.  Of course it won't do it by itself; you must use it to see just how much energy you are wasting.  The purple button labeled KWH Hour selects that useful function.  It will "integrate" power over a period of time (which is the definition of "energy") and show you how much you are using.  A thermostatic electric blanket, for example, although it takes 228W when turned on, requires power intermittently, and after it delivers a full night of warmth you might find that only 1/2kWH has been consumed, worth about a nickel.  Compare that to how much it costs to heat the house or even a room for a comparable period!

KILL A WATT Readout 59.9 Hz The unit measures frequency in Hertz, or "cycles per second."  It is not terribly precise.  The utility company has a long term accuracy of parts per billion and the KILL A WATT only measures three decimal places.  Even so, this is valuable if you are using a generator or a UPS.  Although only clocks care about many decimal places, some equipment might complain if the power source is a few Hz off, and you can easily see that here.
KILL A WATT Readout 112.5V Line voltage is also useful to know.  In this case there are more than sufficient decimal places for any normal purpose.  You can detect overvoltage situations and brownouts.  You can also compare readings with and without something plugged in.  If the voltage goes down a lot with a light load, it means that your wiring is "inadequate" or maybe defective.  If that happens on only one socket, you've pinpointed the problem.  If it happens on multiple circuits, it may be time to call the utility company.
KILL A WATT Readout .70 Power Factor "Power factor" is a relatively new concern.  PF equals one with a "resistive" load such as a light bulb, heater, "warming blanket," and other things that just tend to get hot.  Some electronic appliances will show lower numbers, and this can be a problem.  Rather than explain why, I'll refer to the Wikipedia article on the subject.  If you see a low power factor on a device that also requires a lot of power, it may result in mysterious circuit breaker tripping or other problems.

The KILL A WATT will provide other readingsVA (Volt-Amperes) and Amperes, but they are just different ways of expressing the measurements already discussed.  I'd go into more detail, but these gadgets typically cost around $25 on eBay and your time is better spent getting one than reading about it, since you have now seen just how useful it is.  I've bought a handful of these for home and for work and so far my only problem is that they come in those nasty plastic bubbles that require a jackhammer to open.  Also, the tiny instruction sheet is so thin that it's almost transparent.  But they've all worked and continue to work.  I also checked their calibration with far more expensive and sophisticated equipment and found them to be as accurate as matters.

Summary:  If you use electricity and care about energy waste, you need a KILL A WATT.

I'm waiting to see how the Sunbeam "warming blanket" return goes.  I'm unlikely to freeze since I had a spare available.  However the defective one was a pleasant and festive blue, and the substitute is some horrible "beige."  Fortunately I usually sleep with the lights out, so I think I'll be able to cope until the correct one is returned.

NP:  "The Invisible Man" - Marillion (On Pandora, which seems to have increased their Marillion offerings.)

Richard Factor

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