mm wrote:
Will sunlight damage the electronics of a circuit board?

The power company installed a radio-controlled switch on my air
conditioner, and mounted it on the side of my house. It has an ugly
label which clashes with the natural look of my little yard.

I was peeling it off when I noticed that it covered a fairly darkly
tinted plastic window, and inside the window was the circuit board
that included the receiver and the control that turns the AC off when
the Power Company Central Command wants it to.

There is a much window below the label through which one can see a
green LED. In the late afternoon shaedI only knew I could see the
circuit board because I could see the glowing LED. (Does anyone know
if that means there is power to the AC, or only that there is power to
the controller device itself?)

I stopped unpeeling at that point. I don't want to cause their
product to wear out sooner than normal. I Would the sunlight harm
anything inside?


BTW, after I signed up up for this, a man showed up at my door, handed
me a brochure and then went about mounting the thing to my brick wall.
I watched. He drilled two holes and then two holes for a cable clamp,
all in the mortar, but when it's gone, I'll have to replace the mortar
and the replacement won't match in color. After he was gone I read the
brochure and it said he could mount it to the air-conditioning
condensor if I wanted. I much would have preferred that, so I
wouldn't have to look at the ugly thing at all, label or no label.
But the guy, affable and pleasant as he was, didn't say a thing about
that. The previous device had been mounted to the AC, and didn't have
a label either, but it was a little narrower, and didn't come with
such a long cable.

Thanks.

Starting about 25 years ago, the local power company started a program
whereby they installed these boxes to home AC units and electric water
heaters, supposedly to reduce peak demand on the grid in times of high
demand. A few years later, they returned to remove those units and install
different untis (different brand/model), saying that the originals never
gave them the control of peak demand they needed. Then, about 7-8 years
ago, they again returned to remove all vestiges of the control boxes, saying
that they were too expensive to maintain; frequent failures caused many
service calls to replace them. The end result was that the boxes never gave
the power company the relief from peak demands that they hoped; in all a
waste of time and money.

To your question, it's unknown from your observations whether the innards
would be damaged by sumlight intrusion. There could be a UV EPROM inside
that could possibly be erased if sunlight got to it on a continual basis,
however, most EPROMS have a label covering the window that protects the
contents. Constant UV exposure from sunlight could possibly damage the
markings on components, but they will likely be OK. Most plastics and
glasses are fairly good blockers of UV. If you're concerned about the
esthetics of the label on the box, paint it or cover it with a piece of
tape. That will not harm the box.

The green LED is probably on to indicate to a service guy that the unit is
operational (not in an error condition). Without specific info on the unit,
it's impossible to know its exact purpose.

--
David
masondg44 at comcast dot net