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Discussion Starter · #1 ·
I think my bulb's life got shortened because of a couple power outages, so I figured I better invest in a good power supply backup. Would this one be sufficient?

http://www.bestbuy.com/site/olspage....&ref=10&loc=01


If it doesn't link, it's the CyberPower 800VA Battery Back-Up System w/ 450w of power. No idea if this would do the job, so any advice is appreciated.
 

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Discussion Starter · #2 ·
Nevermind. I read a few threads that said not to get a cheap UPS for you pj. Guess I'll just go with the new bulb then and be done with it.
 

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Quote:
Originally Posted by holyc0w
Nevermind. I read a few threads that said not to get a cheap UPS for you pj. Guess I'll just go with the new bulb then and be done with it.
SO whats the conclusion ?


I think the fact i connected my projection LCD TV to a APC 1100VA ups caused it to die prematurely.
 

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Quote:
Originally Posted by lowspeed
SO whats the conclusion ?


I think the fact i connected my projection LCD TV to a APC 1100VA ups caused it to die prematurely.
Why?


ted
 

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Quote:
Originally Posted by tvted
Why?


ted


I dont think it gives a good sinus.
 

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Your AE700 consumes about 150 watts. A UPS with either a stepped or sine wave output with at least 150 watt amps of output will suffice for the limited number of minutes the UPS will be called on to power your projector. I have a stepped UPS feeding my PT-L300U and over the past two years it kept the projector running fine through several brief power outages and also allowed me to power down during an extended power outage.
 

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Quote:
Originally Posted by Thomas Willard
Your AE700 consumes about 150 watts. A UPS with either a stepped or sine wave output with at least 150 watt amps of output will suffice for the limited number of minutes the UPS will be called on to power your projector. I have a stepped UPS feeding my PT-L300U and over the past two years it kept the projector running fine through several brief power outages and also allowed me to power down during an extended power outage.


SO your saying the projector won't be affected by the quality of the wave output ?
 

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Quote:
Originally Posted by lowspeed
I dont think it gives a good sinus.
But with a proper UPS the PJ would be running off line until there is a loss of power,

so a stepped voltage would not be a factor - as Thomas pointed out from his experience. Anyway the sine wave that the PJ's electronics sees is filtered and converted to DC (which the components use) by the caps in your PJ's supply. So, much of this is dependent on the quality of those capacitors.


If the source was being supplied by the UPS rather than line you are likely to perceive it long before the PJ suffers any damage. What Thomas says is more in my experience. The quality of Power Supplies has long been a particular interest of mine from my days of constuccting Audio components. It is arguable to me whether a UPS actually is a benefit but I doubt it is a harm.


ted
 

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Quote:
I dont think it gives a good sinus.
The bulb, like everything else in the PJ is supplied by DC. The Dc comes out of the power supply circuit, power supplies transform, rectify and filter the incoming AC to the various DC voltages required in the PJ. The 'quality ' of the incoming sine wave does not matter.
 

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The quality of the sine wave matters. Why?


Your power supply in the PJ or anything for that matter uses some sort of rectifiers and caps. Depending on the ratings and how close they run them to the limits will determine how well they stand up to the square/saw tooth waveforms you'll see.


Look at it like this, a sine wave is a gentle sweep up that's not going to slam an active component into conduction, a square wave is on, then off right now, it's hard on some diodes because they're not able to switch fast enough. There are diodes that tolerate that well, but do you know if your's in the PJ are? For what it's worth, it seems that many of the consumer electronics I repair do use high speed switching diodes now that should be fine with this type of waveform. But some of the budget stuff is lucky to work with a normal sine wave.


That said, it's doubtful a UPS made a bulb burn out quickly. When most cheaper ups's are running they are not supplying their own power until something drops the AC line voltage a bit. So you will have a sine wave until the AC goes away, then it goes to a sawtooth or a squarewave, and then is when you risk power supply damage. You usually won't damage things past the supply because the power supply rectifies and filters the voltage so those parts get clean DC. The power supply on the other hand may complain and die. I have seen it happen though when the diode shorts and kills the filter cap and passes AC to a micro before the product blows a fuse. Very rare but I've seen it occur.
 

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Quote:
Originally Posted by cummings66
The quality of the sine wave matters. Why?


Your power supply in the PJ or anything for that matter uses some sort of rectifiers and caps. Depending on the ratings and how close they run them to the limits will determine how well they stand up to the square/saw tooth waveforms you'll see.


Look at it like this, a sine wave is a gentle sweep up that's not going to slam an active component into conduction, a square wave is on, then off right now, it's hard on some diodes because they're not able to switch fast enough. There are diodes that tolerate that well, but do you know if your's in the PJ are? For what it's worth, it seems that many of the consumer electronics I repair do use high speed switching diodes now that should be fine with this type of waveform. But some of the budget stuff is lucky to work with a normal sine wave.


That said, it's doubtful a UPS made a bulb burn out quickly. When most cheaper ups's are running they are not supplying their own power until something drops the AC line voltage a bit. So you will have a sine wave until the AC goes away, then it goes to a sawtooth or a squarewave, and then is when you risk power supply damage. You usually won't damage things past the supply because the power supply rectifies and filters the voltage so those parts get clean DC. The power supply on the other hand may complain and die. I have seen it happen though when the diode shorts and kills the filter cap and passes AC to a micro before the product blows a fuse. Very rare but I've seen it occur.


You know what ? I had a cheapo belkin that only kicks in if the power goes down.



And then i decided hmm maybe i should change it to one that "conditions" the line.... 2 months later the bulb blew....


so i dont know.... could be that the bulb was crap to begin with.
 

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It should not have affected the bulb, as others have said your bulb is not seeing the waveform from the AC mains, it has it's own power supply and should be isolated.


During one of my training schools we discussed bulb life in projectors, specifcally the DLP product we were looking at. The basic theory of bulb life is to not turn it on and off several times. Every time you strike it you lose some life and eventually it will not be able to establish an arc because you ate the electrode away. The best case usage would be to turn it on and use it to watch all your daily watching in one period, of course that's not what people do. So, the people that eat bulbs are those who turn it on to see the news and off again, then an hour later turn it on to watch a show and off again. Etc, multiple strikes on the lamp will shorten it's life span greatly. The way your parents taught you is not correct for any product that uses a lamp, do not turn it off if you're out of the room for a bit and then back on when you come back, that's going to reduce the lifespan.


Out of curiousity, how many hours did you get out of it and how do you typically use it?
 

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Quote:
Originally Posted by cummings66
It should not have affected the bulb, as others have said your bulb is not seeing the waveform from the AC mains, it has it's own power supply and should be isolated.


During one of my training schools we discussed bulb life in projectors, specifcally the DLP product we were looking at. The basic theory of bulb life is to not turn it on and off several times. Every time you strike it you lose some life and eventually it will not be able to establish an arc because you ate the electrode away. The best case usage would be to turn it on and use it to watch all your daily watching in one period, of course that's not what people do. So, the people that eat bulbs are those who turn it on to see the news and off again, then an hour later turn it on to watch a show and off again. Etc, multiple strikes on the lamp will shorten it's life span greatly. The way your parents taught you is not correct for any product that uses a lamp, do not turn it off if you're out of the room for a bit and then back on when you come back, that's going to reduce the lifespan.


Out of curiousity, how many hours did you get out of it and how do you typically use it?
I would say about 1400hours. i would guess i turned it on and off 700-800 times.
 

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Quote:
Originally Posted by lowspeed
I would say about 1400hours. i would guess i turned it on and off 700-800 times.
1400 hrs is not bad for a lamp struck often or not.


You are averaging less than 2 hrs per on time. What might be interesting is the number of on/off cycles per day as well as the duration of off times.


cummings66 is absolutely correct in his description of bulb mechanics and usage vs. lamp longevity.

This is not to say you won't find the exception to the rule - either short-live or long-lived.


ted
 

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Quote:
Originally Posted by tvted
1400 hrs is not bad for a lamp struck often or not.


You are averaging less than 2 hrs per on time. What might be interesting is the number of on/off cycles per day as well as the duration of off times.


cummings66 is absolutely correct in his description of bulb mechanics and usage vs. lamp longevity.

This is not to say you won't find the exception to the rule - either short-live or long-lived.


ted



1400 is aweful.... for a 300$ bulb :)



if it was 10$ 1400 with be ok....
 

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Quote:
Originally Posted by lowspeed
1400 is aweful.... for a 300$ bulb :)



if it was 10$ 1400 with be ok....
It is. It is. ;)

I couldn't agree more.


However it is a bargain compared to some and certainly for those of yesterday.

At your rate that is cheaper than 25 cents an hour - cheaper than DVD rental and certainly cheaper than gas. :eek:


I'm certainly not arguing this is not a blow to the consumer, but PJ bulbs have never been cheaper than they are currently and this after all is a rarefied interest and lamps should be factored into the cost of ownership. One a year is good for me - depending on usage of course.


ted
 

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Quote:
Originally Posted by tvted
It is. It is. ;)

I couldn't agree more.


However it is a bargain compared to some and certainly for those of yesterday.

At your rate that is cheaper than 25 cents an hour - cheaper than DVD rental and certainly cheaper than gas. :eek:


I'm certainly not arguing this is not a blow to the consumer, but PJ bulbs have never been cheaper than they are currently and this after all is a rarefied interest and lamps should be factored into the cost of ownership. One a year is good for me - depending on usage of course.


ted


For a projector yes.. for a TV no.
 
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