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Episode 060724 - Lies in Consumer Electronics
Anyone have a good story about a run-in at an electronics store? Anyone know any other things those guys lie about in order to sell more goods?
Comments
-sorry if you mentioned this in the show, I haven't had a chance to listen to the whole thing yet.
A laptop doesn't really have a UPS. If I plug my laptop into the wall it uses the power from the wall directly. I can take the battery completely out of my laptop and it will run on wall power. However, if the power goes out, the laptop switches to the battery. So a laptop doesn't technically have a UPS. But from the perspective of a user, a laptop acts as if it had a very awesome UPS. So plugging your laptop into a UPS is silly, just plug it into a surge protected outlet. As for cellphones, I'm not sure if they run off the battery or the wall when they are plugged in. It probably depends on the specific phone model.
Catch - a good number a cellphones WILL NOT work without the battery connected to the unit while plugged into an outsides power source.
Best Buy tried to get me to pay $6 for an extended warranty on a cordless phone that was $11 after rebate. The extended warranty was only for 1 year.
I put the odds of the phone breaking during the first year at about 1 in 500, especially since any pre-existing defect would be discovered during the return period. I am sure that the warranty did not include the battery. I'm also sure that you have to pay shipping to get your item serviced. Needless to say, I passed. I think I can "self insure" an $11 item.
The slightly more expensive (but still real cheap) ones have what they usually call AVR. There are multiple ways of them implementing this, but basically you still get the mains AC passed direct to your PC, but it is also able to adjust for small changes in power on the input to clean up the output. If there is a major spike or brownout, it will switch to full backup mode for a few seconds then switch back. I have this type of UPS, and I know when there was a slight surge or brownout because it will switch to battery for a few seconds then go back even though nothing else in the house shuts down.
What you are describing is an "online" ups, where the load is always running off the battery. In realty, they don't really run off the batteries though. They simply run an AC to DC (charger) then DC to AC (inverter) 100% of the time. The batteries sit in the middle so if the AC to DC converter shuts down the DC to AC converter is not starved for power. There is no need in this case to switch at all. In general, you don't really want this type of UPS in your home. They are a lot more expensive, and require more maintenance because the inverter is doing a lot more work. They also generate a good amount of heat and require better cooling. This is why most UPS devices will be noisy when on backup power, as they need the fan to cool the inverter.
Another thing to note is the power from consumer UPS devices while on battery is not generally as good as mains AC. The output is generally a "stepped sine wave", which is usually printed as a feature on the box. What that translates to is you will get a stair step effect on the output instead of a smooth analog signal, which means more frequency harmonics. For the most part your equipment will not care either way.
I've never worked with non-data-center UPSs before in my life, and in fact this is the first one I've ever owned. ^_~
However, last year, I was in the market for a digital camera (since I've never really owned one) and someone tried to help me. He told me a whole lot of things about all different cameras, all of which was suspicious and vague. I tested him with a question that he should have been able to answer (I knew the answer, but it was a test) and he didn't even know what I was talking about.
Then I left the store.