DLP - Leave it on or turn it off?

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Leave it on if you think you will be using it again within the next hour. Go ahead & turn it off if it will be longer than that. That's the rule of thumb I have used with my Samsung DLP. My original lamp has 6500 hours on it.

Leaving it on 24/7 will eat up bulbs...

I agree with jedvik's statement. It's hard to say what's the most optimal point in doing this. 5mins off is way to short, 2hrs left on w/o a view is way to long. Gut feel tells me that somewhere in the 30-60min range is optimal, but then it's my gut feeling.


CCourtney

Remember, there's more than just the bulb in the TV. The color wheel spinning at X,000RPM, and a whole bunch of electronics inside, its not just a question of bulb life.

Juliox,


The life of the color wheel and electronics are going to be minimally affected by power cycling vs leaving TV on.


The major concern with these sets is the bulb as it IS a consumable item (i.e. expected to be used up multiple times during the life of the set.)


CCourtney

Isn't there already something built-in that will handle that? I know on other microdisplays that if you don't have a source signal on your input for x number of minutes, it will automatically power off.

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This is true but unless you shut off the STB (you may have to unplug it as I believe the Motorola still sends the signal) it will have a source signal.

I agree with the one hour rule. Restarting a lamp that has not cooled sufficiently seems to be the formula for short bulb life. By the same token, I wouldn't leave it on 24/7 either.


Our 27 month old HLM507W probably has less than 1200 hours on it now. I'd share my exact lamp hours, but its not worth a lamp cycle to check it very often.

AFAIK the bulb doesn't need to cool before being turned on again. The biggest thermal stresses occur when the temperature swing is a maximum at maximum rate, i.e. from cold to hot. From warm to hot is not as bad, and from hot to cold is probably the least harmful since its gradual. BTW, when you turn your TV off the bulb stays on for a while just in case you didn't mean to turn it off. This means you can turn it on again quickly without stressing the bulb.


Bulb deterioration is proportional to the length of time it has been on. Deterioration is also proportional to the number of off-on-off cycles. So the question is, is it better to leave your TV on for an hour when you're not watching it, or turn it off and subject the bulb to an off-on cycle? I don't know the answer, but I'd be inclined to turn it off. I don't want my tv to start running my life.

If it's going to be more than 5-10 minutes until you watch again, I'd turn it off. It's probably not ideal (30-60 minutes is probably better), but you never know when something else will come up anyway, and that short amount of time turns into a longer amount of time.


I think the biggest stress is turning it off, and then turning it back on before the fan shuts off (I think it says this in the manual). I definitely wouldn't leave it on all the time, though. AFAIK, no matter what the screen is showing, the bulb is still on, at full wattage. It's just the mirrors on the DLP chip that are turned to not show the light.

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I think that may be a few seconds, but it's the fan that stays on for a minute or so, to cool the bulb off. But if you "accidentally" turn the TV off and the bulb itself goes out, you're supposed to let the fan finish cooling the bulb before turning it back on. I think it says this in the user manual as well. I know the technician said it as well, when he replaced a noisy color wheel last year.


For example, when you go into the service menu, you have to turn the TV off. But you can enter the button sequence fast enough to bring up the service menu before the bulb actually turns off, which is ideal.

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Exactly. You should avoid turning the TV back on before the fan shuts off it at all possible - usually about 1 minute or so. I know I can see the bulb turn off after a few seconds, hear the fan shut off, and then there is a click when the "power" shuts off (not sure how much time between the last two, though).