Windows 7 Wattage Spikes


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Due to the fact that my apartment complex put out a notice that one day this week, there is going to be a total electrical blackout, while some kind of A/C repair is done, I'm planning on buying a small generator from Harbor freight.

I know that the one I have in mind, because all that I plan to connect to it is the computer, a light and a fan, but I was monitoring PC power usage in PowerChute and I noticed that while it was normally using 246 watts, on occassion it would spike to 258 or 264 watts. It's not really important as far as taxing the generator, because it's rated at 800 watt continous, but it still made me curious, because I changed nothing in usage on the PC during those spikes. What would cause spikes of this kind, lasting only a few seconds each time?
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What would cause spikes of this kind, lasting only a few seconds each time?
Lots of things, all perfectly normal. Because of the way computers work, they are NOT pulling the same amount of power all the time. Drives spin up and spin down, memory is used then let go, the CPU does a task, then goes to idle waiting for the next task. The graphic solution (often the most power hungry component in our computers) is suddenly tasked to display a bunch of animated objects, then goes back to the plain desktop.

All these things cause power demands to fluctuate.

That said, I am not keen on you running your computer directly from a home generator. Most portable home generators are designed to power heavy duty appliances (refrigerators and freezers) or motorized tools or air compressors and the sort. Not sensitive computers and as such, most home generators don't have the best output power regulation to ensure anomalies (often from fluctuations in revolutions from the generator's lawn mower engine sputtering, or missing a beat) don't disrupt the computer's operation. Also, grounding (Earthing) the generator's output can be tricky - typically requiring pounding a long copper grounding spike into the ground, then tying the generator's ground to it.

Because high-speed digital electronics need "quality", stable power, I STRONGLY URGE you to get a "good" UPS with AVR (automatic voltage regulation) to use at all times, but for sure, while on generator power. I emphasis "good" because, like power supplies, there are good UPS and cheap UPS. Something like this 1000VA APC UPS with AVR would suit you fine, protecting your computer, your LCD monitor, and your network gear. Like power supplies, there is really no such thing as "too big" as the system will draw only what it needs. But like power supplies, the larger models tend to have the higher-end features and components.

Understand a surge and spike protector is little more than a fancy and expensive extension cord that does absolutely nothing for anomalous "low-voltage events" like dips (opposite of spikes) and sags (opposite of surges), or brownouts (long durations sags). And for anomalous "high-voltage events" like surges and spikes, all a surge and spike protector does is chop off the tops ("clamp") of the voltage sinewaves - leaving a not-so-pretty mess for the PSU's filters and regulators to clean up. The better UPS will use it's AVR circuits to regulate the power into something easier on your computer's PSU.

If the anomaly is too extreme (high or low) for a surge and spike protector, they typically just kill power, causing the computer to crash, potentially corrupting hard drives. Hardly beneficial, IMO. But an UPS, on the other hand, will sense the extreme conditions and simply flip to battery power only to keep your system running AND isolated from destructive power.

Note until now, I mentioned nothing about an UPS providing backup power during a complete power outage - that's because battery backup is just the "icing on the cake". The "bread and butter" (I must be hungry! ;)) of a "good" UPS with AVR is the automatic voltage regulation.

That said, an UPS will typically have enough battery power for 20 to 30 minutes of backup power - so sorry, but an UPS is not likely able to provide power for the entire outage during the AC work being done on your apartment.

And for the record, I recommend ALL COMPUTERS BE ON A GOOD UPS w/AVR. I also have an UPS on my big screen TV and home theater equipment.
I also have an UPS on my big screen TV and home theater equipment.
Same here, but as you have indicated, they don't solve my problem. However, I have been discussing the issue elsewhere and have decided that there in no practical solution that I can afford. The generators are out because of a combination of safety and legal reasons. Inverters are out due to expense of the combination of the inverters and the number of batteries it would require to operate it as long as needed. Solar is out due to expense, so it appears that I'm out of luck, and will have to grin and bear it.
Well, in my experience, scheduled outages either last much longer than planned, or much shorter than planned. Hopefully yours will be the latter and you will not be without power for too long - and the day will not have record high temperatures. Still recommend a "good" UPS with AVR, however.
That is a concern for me also, because according to the forecast, the weather that day has a 60 percent chance of rain and thunderstorms, which I suspect would have an effect on the contractors being able to do their work, assuming that it is done outdoors, and may not finish according to schedule. The following day still has a 30 percent chance of the same, so the outage may get extended.
Didn't pay too much attention to your comment regarding an UPS, because I already have one. However the blackout was postponed (probably due to thunderstorms that day), and I've now got a bit more time to prepare for whenever they decide to reschedule it.

I ordered a DC Fan: Portable Camping Fan Blower w Rechargeable 12volt DC Battery AC Power Supply | eBay

Which hopefully will take care of cooling, and now I'm trying to determne if there is a practical way of keeping the PC powered. I have this APC: New APC BX1000G Line Interactive UPS 600W 1000VA Power Saving Back UPS | eBay

Which only provides ~19 minutes of backup power at my normal power usage, and I might be able to milk a few more minutes by only running essential components, but for this situation that is next to nothing.

Since I have a spare automotive 12v battery, I got to wondering if there is a practical means to connect it in parallel with the battery in my UPS ? It would seem that if the little battery in the UPS can provide 19 minutes, the auto battery ought to be able to give a couple of hours or more of power, if it could be channeled through the UPS. I do not want to go into anything to major, but is there an easy way to accomplish this?
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I got to wondering if there is a practical means to connect it in parallel with the battery in my UPS ?

No. For one, I would not put two different battery types in parallel, but also, at this point, we don't know how the cells in the UPS battery are configured. It uses two 7aH 12V SLA cells, but we cannot see if they are wired in parallel for 12V or series for 24V. It could be either. Some UPS use 6V cells, then "step-up" to 120VAC. Plus, you would be introducing a lot more amps to the UPS regulator/charging circuits than it was designed for. The better solution if you wanted to use a car battery is to buy an inverter. But still, depending on the power requirements of your computer, and the condition of the storage battery, I am not sure you will still get a lot of runtime - unless you had several car batteries in parallel.

The ONLY solution I see to provide coverage during extended power outages as this situation appears to be is to use a gas powered backup power generator/inverter.

BTW, 19 minutes of backup power from an UPS is considered pretty good. After all, the idea behind an UPS for "backup" power is to (1) prevent data loss during a sudden loss of power and (2) provide enough time to save any open documents you are working on, exit all running programs, then "gracefully" exit Windows and shutdown the computer - and that takes less than 5 minutes.

Personally, and not knowing all the details so this may be impractical, but if my place was going to have a "scheduled" extended power outage, I would arrange to work some place else that day.
Personally, and not knowing all the details so this may be impractical, but if my place was going to have a "scheduled" extended power outage, I would arrange to work some place else that day.
That seems to be the consensus of most others that I have been talking online to, but there are two reasons that I won't...I'm somewhat disabled and more than a little reclusive. That is why I consider my PC to be important, it is the means by which I accomplish a lot of things. Still, I guess the world won't come to an end if I have to do without it for one day. I just hope that doesn't grow into two.
Just got the notice that the blackout is rescheduled for next Tuesday. If the forcast holds out, it will probably be done this time, because it doesn't mention any chance for rain this time...only being hotter. I hope that fan arrives before the lights go out, because if it doesn't it may force me to go to the other building, which I do not look forward to at all.
And they didn't tell you how long they expected the outage to last? That is odd. I don't see why facility power has to be out for A/C work, other than maybe for a short "cut-over" period. I would think they would have everything physically in place to make the actual power outage as short as possible. I can see being without AC for a long time, but not power. Food starts to spoil and/or thaw, and some people may have medical devices with limited, if any battery backup. Aquariums need aeration and of course, the DVR!!!
No, they said that the power would be out from 8:00AM to 5:00PM, but as you mentioned previously it could go longer than expected. I agree about the time involved as being too long for anything that I understand. Hopefully that have just set those times to cover their tails...but who knows?

I got an email from the fan seller, verifying that it actually was physically shipped today, but the projected ETA is one day late, and the last time something was shipped to me via USPS Parcel Select, it took the scenic tour of the US, before it finally arrived.

Since the fan is only being sent from one state away, I will cross my fingers and pray. I just met the postman at the door and advised him about the blackout, and the expected shipment, but even if it shows up on Tuesday, it won't be of too much good, because it takes 10 hours to charge the battery. I may have to use the auto battery instead.
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My fan arrived yesterday, just in time for getting the battery charged up for today. I've tested the fan on my auto battery and it puts out a nice stiff breeze, so I guess that I won't melt. I have a feeling that it will get used a lot more than one day due to it's portability, it can blow most anywhere...on the balcony, working on the car, etc.
From your keyboard, to God's ears. The power came back on about half an hour ago. I waited this long to post, just in case they would power off things again. If the management hadn't so conscientiously warned us about the power, I would probably have slept through the entire time, instead of worrying about it.
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If the management hadn't so conscientiously warned us about the power, I would probably have slept through the entire time, instead of worrying about it.
lol Maybe. Or the sudden silence would have woke you.
With my neighbors...there is never any real silence, except for a few hours in the middle of the night, which is usually broken by police and ambulance sirens at erratic intervals. Which is part of the reason that I have become a night person, with the hum of my computer to keep me company.
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Sometimes I feel that someone should invent a device that would receive signals from emergency vehicles that wouldn't require having everyone else having to listen to them. But then, I imagine that some pedestrian would get run down by them. Still it would be a good idea so that someone listening to their boom-box while driving would become aware, and not run headlong into them, or block their lane of traffic. It would require a very weak RF signal, so that drivers wouldn't be receiving other signals across town or miles away. 1/4 mile reception should work.
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