PIR vs. Computers

Just wondering if there's a risk of false alarms on a motion (DSC's BV300, not pet immune) which faces a computer about 12-15 feet away (blinking led's, screensavers, etc.)

It's been good so far... just don't want to have any problems over Christmas when I'm gone.

Reply to
shady
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A Passive Infrared detector looking at a computer isn't a problem, unless the computer is on wheels and happens to roll across the room. :-)

The LED's don't put off enough heat, and are too small anyway. The fan should be constant, and the air volume is small, so that shouldn't be a problem. Screensavers, or any "movement" on the screen is invisible to the PIR, since it is looking for changes in Infrared background radiation, and "motion" on the screen is invisible at Infrared wavelengths.

Think "Night Vision"- That's Infrared.

Reply to
Stanley Barthfarkle

Unless you're using your computer as a fax machine or server leaving it "on" and completely unattended isn't a good idea. A fan failure could result in damage to your machine, for instance. It's best to turn it off and unplug it from the wall. If you're going away for any length of time, unplug your appliances and TV's as well. More importantly (and depending on where you are) in colder weather, make sure you leave a set of keys with a friend or close aquaintance so they can check on the house every two or three days. Some home-owner's policies I've seen have clauses that state the insurer considers the house "abandonded" (with respect to any cold weather related claims that may arise) if no one's been there for more than 72 hours (so make sure they log or document their visits as well). In Edmonton (where I lived for about fifteen years), that was a pretty standard clause. Turn off the water to your toilets and to the hot water tank (it's a good idea to shut off the gas to the tank or turn of the electric breaker to it as well).

Reply to
Frank Olson

and completely unattended isn't a good idea...

Wrong. Your PC will last longer if you never shut it off than if you do so daily.

I've been using personal computers for decades. My first was an Apple II. I've had at least four machines running all the time in my office for over 15 years. To date I've had exactly one fan failure. That was on a server that has three fans so there was no real heat buildup anyway.

You could also disassemble it and place each component in its original shipping container each night if you want... :^)

Don't forget to power down the fridge each morning before you leave for work, too.

you leave a set of keys with a friend or close aquaintance so they can check on the house every two or three days.

That will keep the PIR from falsing, right? :^)

considers the house "abandonded" (with respect to any cold weather related claims that may arise) if no one's been there for more than 72 hours...

What a crock of Olson. Do you sit up all night thinking this stuff up?

Was that before or after the time you claim to have snap-rolled a 737 at 5000 feet AGL?

to shut off the gas to the tank or turn of the electric breaker to it as well).

Uh-huh. Turn off the gas supply in Edmonton, Alberta, Canada when you go away for more than 72 hours. I wonder if the insurance company considers burst, frozen pipes an indication that the house has been abandoned or if they simply chalk it up to absolute stupidity.

Reply to
robertlbass

and completely unattended isn't a good idea...

I wasn't suggesting he turn it off daily. Your reading skills haven't improved much, have they??

Uh-huh... try unplugging the fan for your CPU and see what happens. I don't care how many fans you have built in to your case, a failure of the CPU fan will put a major "damper" on your day.

Excellent idea!! About as good as running a short 6' length of wire up into the attic from a door contact and then splicing it (as you had so unwisely suggested in a forum of alarm professionals only a few days ago).

Heh... Or you could just put your those items that require refrigeration in the garage (depending on where the OP is located)... :-)

you leave a set of keys with a friend or close aquaintance so they can check on the

Yup. They could keep the fish alive if they fed them while they were checking things out too.

considers the house "abandonded" (with respect to any cold weather related claims that may arise) if no one's been there for more than 72 hours...

Nope. Spent a number of years working in an office of independent insurance adjusters. I thought you knew that about me.

Where/when did I claim that??

to shut off

You *really* have a problem reading, don't you?? I would suggest a few remedial courses at the local high school. That would probably help you study for the State alarm licensing exam as well...

Reply to
Frank Olson

I hafta always let bass get the last word or I get his mom calling my mom, you know the routine. But I am curious about this leaving the damn things on 24/7 ? I can't see any advantage, the hard drives still stop spinning, is it better for the fans not to start and stop? Inquiring minds want to know.

And what are you other small fry doing about outages and such? I operate an office and shop out of my home and have a modest generator... powers the phone system, 2pcs and the furnace and I have something called Ibackup saving stuff online somewhere.

And now radies and gentimen... mister awrec baaaawww> >>Unless you're using your computer as a fax machine or server leaving it

"on" and completely unattended isn't a good idea...

make sure you leave a set of keys with a friend or close aquaintance so they can check on the

considers the house "abandonded" (with respect to any cold weather related claims that may arise) if no one's been there for more than 72 hours...

standard clause.

good idea to shut off

Reply to
mikey

Robert is correct. Is less stressful on the CPU if you leave the computer "on" 24/7. The "power on" self test that most computers undergo puts the most stress on the components. Most computer builders suggest leaving the thing on. I like to stress that if you do, it better be in a well supervised environment. The chances of an Intel supplied CPU fan failing is remote, but I have seen it happen. Sometimes you get adequate warning of an impending failure (the fan will start "buzzing"). When you hear that it's best to try and track down which unit it is (for instance, a case fan failure isn't as critical). The cases we've settled on all have direct ducting to the CPU so the fan is pulling air in that's room temperature. Most cases I've seen are circulating air that's already inside the case and which is a few degrees warmer than room temperature.

My CPU's temperature is 29 degrees C. My motherboard's at 24 degrees C. The room I'm in is at 20 degrees C.

If you're going away for an extended time (more than three days), it's best to do as I suggested.

Reply to
Frank Olson

Frank, one other thing I have noticed. Offices of all types seem to generate an inordinate amount of dust. I think it comes from the amount of paper that is used in an average office. I had an AMD system start to do the fan "buzzing" thing, then I started to smell that foul smell of plastic burning. I immediately shut the computer down and opened it up. Seems the CPU fan was totally clogged with large balls of dust, which almost cost me a CPU.

If you're gonna run your computer 24/7, and it's one used in an office, it might be a good idea to open the case once a year and vacuum it out thoroughly. I couldn't believe the crap inside this computer...

RHC

I choose Polesoft Lockspam to fight spam, and you?

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Reply to
R.H.Campbell

Good point, Rob. There are filters available and they do help, but there's no way to completely seal a case (and you wouldn't want to since that would hinder airflow around the components). Never leave your CPU sitting directly on a carpeted floor. Set it on a piece of plywood or other hard, easy-to-clean surface. You can get yourself one of those computer cleaning kits from your local electronics shop. Rat Shack used to sell a nice one, but it was a bit "pricey" for what you got.

Reply to
Frank Olson

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perfect video for this thread... the rest of the site can be interesting too

Reply to
shady

If you unplug everything then be sure that you get those plastic covers that plug into empty outlets... You don't want electricity leaking out of the sockets and getting all over the floor.

I actually knew an old woman in my neighborhood (when I was a kid) who believed this and always had something plugged into every socket in the house.

Reply to
JoeRaisin

Excellent idea, Joe!!! You don't want to come home to puddles of electrons all over your carpet!!!

Reply to
Frank Olson

any advantage, the hard drives still stop spinning, is it better for the fans not to start and stop?

Modern PC hard drives generally outlast the service lives of the PCs in which they reside. The biggest current draw is usually the screen and that shuts off automatically as well. The major difference is the amount of stress placed on the various components during power up/down cycles.

Probably so but I'll answer you also.

I liked having a genset that could power everything in the house in CT. The problem with our current home is it would require a 20kW system so I'm setting up a smaller unit to power just the office, kitchen, HVAC and garage. Fortunately, power outages in Sarasota rarely last more than a few hours.

Regards, Robert L Bass

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Reply to
robertlbass

Yep... very messy and dangerous to boot...

Reply to
JoeRaisin

"JoeRaisin" a écrit dans le message de news: b8Alf.1911$ snipped-for-privacy@fe07.lga...

And its costing a lot these days..

One thing to consider if it ever happen to you is that you don't use a metal bucket to collect the spill.. ;-)

Reply to
petem

A metal bucket is OK as long as it's properly *grounded*!!!

Reply to
Frank Olson

"Frank Olson" a écrit dans le message de news: k0Olf.69636$Gd6.9194@pd7tw3no...

yeah and how do you suppose you will fill back the plugs with a grounded bucket?

Reply to
petem

Use a WEBTV, Mikey. They never act up. Just ask Mark :-)

mikey wrote:

Reply to
He's not white...He's PINK!

That's a "toughie". I'd simply suggest disposing of the electrons in an environmentally friendly way... Take 'em down to your local electricity provider and recycle 'em.

Reply to
Frank Olson

I am ok with this..Recycling is good...

But as i am typing this i start to wonder..would it be legal to deposit those loose electron into a power generator winding,and expect to have gasoline back from the motor?this could start a pretty damn big market of contrebande fuel,and poeple could get hacked in there home to get the lost electron from the unused plug in there house...we better keep that quiet ;-)

Reply to
petem

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