Wednesday, May 18, 2011

The electric blanket incident which I learned to turn the thermostat up in order to cool off.

Wait - what?  How does that work?

I am sure that I have mentioned before that the task of making the bed seems be my assignment.

And I may have mentioned that we have an electric blanket on our berth.

How do these two threads tie together?  Like this: The berth is queen-sized (in width, anyway), so the blanket is too.  And when you buy a queen-sized electric blanket, it seems that they always come with two controls, one for each side.  Is it coming together yet?  One for which side?  Yeah, that's the ticket. 

When making the bed one time, I accidentally inverted the blanket.  It is easy to do - it looks the same on the top and the bottom surfaces, and things are always hard to see down at the foot of the bed, in the cave under the overhang from the aft deck.  But I didn't know I had done it.

Net result:  the controls now controlled the opposite side of the blanket.  That is, Jane's control now ran my side, and mine ran hers.

So we went to bed.  And I woke up warm not long after falling asleep.   So I adjusted my control down a couple of notches and fell back asleep, thinking that I had things handled.

I woke up again, a while later, but now I was definitely HOT!  I turned off my blanket and tried to fall asleep again.  It wasn't getting any cooler.  And while in that weird state between sleep and awakeness, when your subconscious and your conscious seem to be able to communicate (tho darkly), it came to me that the blanket was inverted.  And the solution?  To cool off I needed for Jane to turn her side down.  And I didn't want to wake her up enough to be able to explain the situation.  So I turned my control all the way up

Sure enough, in a little while Jane became restless, and then turned down her control.  Blessed coolness!

It took a few more iterations to close in on the right combination of temperatures for both of us to be comfortable.  I'm sure that this would make for an interesting control system design problem and an interesting Bodé plot.  But I didn't do the analysis, I simply flipped the blanket over in the morning.

It seems that our inverter kills electric blankets.  More specifically, it kills electric blanket controllers.  I have learned to unplug the electric blanket before I turn on the inverter - something that prevents us from using the electric blanket at anchor.  Does anyone else have this problem?

(You folks cruising in the tropics:  no cracks please.  It will get warm here.  Some day.)



Drew Frye said...

I'm not surprised. Our inverter kills microwaves (it has the watts but is not sine wave). It also causes hum on the DVD player.

The cure is either a better inverter or--gasp--blankets:)

bob said...

Ours (it's a Heart) does fine with our microwave, and the DVD player works great. But it kills electric blankets. There's always a blown resistor in the controllers.


Related Posts Plugin for WordPress, Blogger...