I’ve heard that electronics equipment wears out quickest when it is turned on and off a lot, compared to being left on for a long time. I don’t know if that is true or not and in particular I’m concerned about my 50" LCD TV. Family members watch a bit, then either leave it on or shut it off when they leave. I’m not sure who to correct, if anyone…those who leave it on when they are done, or the ones who shut it off and walk away. I’ll wager the TV is on about 6-8 hours a day anyway, but that is spread out from AM to bed time.
I’m less concerned about electricity expense than I am about TV durability.
I’m no electronics expert, but my understanding of this issue when it comes to computers is that the process of turning the computer on and off results in changes in temperature (and attendant expansion and contraction) that can have an adverse effect on the life of the equipment.
The thing is, though, that some computer components, especially the processor, run quite hot during normal operation, so there can be considerable temperature changes between their running temps and their switched-off temps. I don’t know enough about the internals of modern televisions to know whether they would experience similar temperature fluctuations.
Even with computers, though, my reading suggests that there is no unanimous opinion about the issue of leaving it on versus turning it off. Any decision to leave the equipment running rather than switching it off needs to also take into consideration the fact that there will also be wear on the components if they are left running. Working out whether the strain of hours of unnecessary operation outweighs the strain of switching the TV off and then on again is probably not an easy thing to do.
If i were you, i’d just switch it off when you’re not watching it. At least you’re being responsible with your power use that way, and i can’t imagine that it will shorten the life of your TV by any appreciable amount.
It should be noted that if you are concerned about this, you’d avoid changing the load on your CPU as much as possible, since modern CPUs in particular (especially those with turbo/boost modes in addition to power saving modes, which now includes desktop CPUs) vary dramatically in power consumption with load, which in turn leads to significant temperature fluctuations, much more often than simply turning the computer on and off (the CPU die temperature also fluctuates much more than the heat sink temperature due to thermal resistance and heat capacity; see the examples here; temperature jumps up/down ~20C in seconds, with a much smaller and slower rise/fall over about 5 minutes due to the heatsink warming/cooling).
Just to clarify concerning computers. Think about servers. They never get turned off until a failure or update occurs. My home server never goes off unless I experience a power failure about twice a year. It has been running 24/7 for over 5 years. However, I do not keep the server monitor on. Only when I need to access the server computer itself. However, the server is located in the basement where it is significantly cooler and as a result transfers heat very readily.
You are correct that the CPU and other components run hot during normal operation. But the operative word here is normal. Yes, manufactures are trying to bring down the operating temps. but its not a problem. My regular desktop computer that I use on a day to day basis is usually turned on in the morning and off at night or unless I’m leaving the house for more than a couple hours. I only turn it off at night because I hate to see the power being used for no reason.
I don’t know about flat-screen TVs, seeing as they have no moving parts, but as far as desktop computers are concerned mine is never off unless we lose power. While it’s running I have zero problems. Every time it is turned off and must be turned back on it’s hell trying to get it to boot. It usually takes me 4 or 5 restarts and some cursing and maybe even a whispered prayer or two to get it to boot into Windows, but once it’s there it’ll stay running with no issues for weeks at a time. It’s about 10 years old and has had a few part swaps (power supply, RAM). So I never turn it off unless I absolutely have to, usually to blow the dust out every few months.
I appreciate the comments and attempts to correlate with PC experience. I myself generally leave PC’s on because they have analog power supplies and my experience has been that they do better when left on, and simply put to sleep mode when not being used.
However, as to a modern LCD TV and its power supply, are there any real TV techs out there with some info to share?
All power supplies are “analog.” However, both PC and TV powers supplies are switching, as opposed to linear. The amount of electricity wasted by leaving a large TV on all the time will more than make up for any reduction in lifetime. IMHO, it shortens the usable life of a TV to leave it on all the time - if it’s an LCD, you are using up the backlight lifetime, if it’s a plasma, the screen itself has a finite life, and if it’s DLP, well those lamps are expensive, and have a short life to begin with.
When you turn off a modern TV, you generally aren’t really turning it off anyway. You’re basically putting it into “standby”.
If you’re plugging your TV into a switched outlet and turn it off and on by flipping that switch, THEN maybe you’re doing some sort of damage to it over time (still probably not as much as leaving it on 24/7, though), but not just by pushing the power button.
My main concern on powering up devices is voltage transients. A bit of extra current reaches a part of a circuit that is higher than expected or the circuit is up and running enough to handle it yet.
With modern PCs (love that term), the PS provides a “voltage good” signal that tells the MB the PS is fully stabilized and so the MB can start the boot up process. This cuts down, but doesn’t eliminate, such transients.
Modern TVs are becoming very PC like. So I suspect they also have “voltage good” signals and transients are less of a problem for them as well.
But still, just clicking the set on and off for fun is probably not a good idea. Especially for the display elements.
If you bought a “lemon” TV set that is going to fail within a few weeks, the number of power cycles you run it thru is the most important variable in how long it takes to fail. If the set survives the initial break in period, then other factors start to dominate. In particular, cumulative effects of heat on the components.
The background electricity used by a flat panel TV is nothing compared to an old CRT set in off-but-ready-to-come-back-on-in-an-instant mode.
A somewhat related question (this seems to be the place to ask, so I apologize for the slight hijack):
My Vizio tv is about six months old, and it takes forever to turn on. After hitting on the “on” button, it’s usually about 15-20 seconds before the tv actually turns on. It’s doing something, because the power indicator light turns on immediately, but I have no idea what.
So while I can’t flick my tv off and on, I’m a little curious as to why.
This doesn’t make much sense (current also isn’t the same as voltage); a well-designed power supply isn’t going to be throwing out random voltage spikes, whether it is starting up or otherwise (I make my own circuits, including switchmode power supplies, so I have plenty of experience in this area; some cheap designs can have a voltage overshoot on power-up but this also implies that the power supply isn’t very stable).
Has it always been like this? If not, then there may be a problem developing; this is a common symptom when cheap defective capacitors start to fail (worsens until it no longer turns on). Although I have seen others talk about the same problem being present from the start (but why would a LCD TV take as long as a CRT TV to come up? LCDs can start operating immediately).
They start instantly, but don’t necessary display instantly. As I said, many do some channel diagnostics when they start. For example, mine will detect new digital subchannels on startup without going to the menu and doing it manually.
I’m no techie, but to interject some information on my particular LCD screen - mine goes into standby and turns the display/backlight/sound off after 5 minutes of no signal. I wouldn’t think that was a bad thing to do if the manufacturer made it to do that. I generally turn it off (it’s 5 years old), but if I forget for some reason, it basically shuts down in short order anyway. In standby, the mfr logo stays lit, so I know whether I actually powered it off or not. The only long-term wear effect I’ve noticed after 5 years of use for hours a day is that it is, indeed, prone to burn-in a little easier than it used to be (it’s a 37-inch in the living room, with a desktop hooked up to it as well as DVD and TV). Ive noticed burn-in along the top where the web browser design stays stagnant for hours at a time. It goes away after a couple of movies or leaving it on a white screen for a bit.
It’s an LCD. Not sure what specific type. And to address the other questions, it’s done this since day 1, and it doesn’t seem to be taking any longer than it first did. I’m guessing maybe a combination of warming up as AaronX speculates, and searching channels, etc as srzzs suggested?
CCFLs do have some turn-on delay, but they come on right away and take a minute or two to reach full brightness, sort of like CFLs but faster (for those confused about acronyms, CCFL stands for cold cathode fluorescent light, which is directly driven by high voltage instead of using heated cathodes and lower voltage; in theory, they can come on instantly but they need to be warm for maximum efficiency). One way to tell if the TV is waiting for the backlight to warm up is to see if the screen comes on (the backlight glow will be visible) but remains black until it completely comes on.
In any case, it seems to be a TV-specific issue; LCD computer monitors are pretty much the same as TVs as far as the display is concerned (they may even use the same panels) and the ones I have seen come on in a second or two. Not all TVs have this problem either; I wonder if you can disable auto channel detection if that is the reason.