[net.physics] Electric Blankets

KATZ%USC-ISIF@sri-unix.UUCP (02/29/84)

From:  Alan R. Katz <KATZ@USC-ISIF>

Does anyone know how electric blankets work?  It has been said in
this list that the thermostat is in the blanket itself, and I would
tend to believe that because the temperature regulation seems to 
work (ie if its set low, it doesn't stay on alot).  However, the
control box with the knob on it seems to be a thermostat, it
clicks on and off with temperature, and there doesn't seem to
be any thermostat in the blanket itself that I can see.

If the thermostat is in the blanket, what is it like and how does
it make the control box click on and off?  

If it is not, and the thermostat is in the control box, how does
it regulate the temperature of the blanket?


				Alan

PS, I am pretty sure there is no thermister or any other electronic
type components here, these things seem to be mechanical.
-------

FtG@rochester.UUCP (Gary L. Peterson) (03/05/84)

From: FtG
Electric blankets (and mattress pads) dont' (usually) have thermostats.
They operate purely on a timing cycle. At lower settings it comes on
infrequently and at higher settings comes on nearly continuously.
Hence the E per delta T varies accordingly. Check into Consumer Reports
two months ago for more info.
					'tis true
					FtG
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