T5 lighting bulb life

[dave]

I see many posts and some retail sites suggesting that bulbs be replaced every 6 or 12 months, yet I don't see any data published that shows were lumens have been reduced to a point of them needing to be replaced.

Has anyone seen a study?

 

[stickx911]

Dave;289513 wrote: I see many posts and some retail sites suggesting that bulbs be replaced every 6 or 12 months, yet I don't see any data published that shows were lumens have been reduced to a point of them needing to be replaced.

Has anyone seen a study?

retail of course wants you to replace more often. I'd say if you do not have a par meter (which I assume you do not), you can just settle with 12 months plus some head room for error. Or if you get some types of algae growth that sometimes signify its time for new bulbs.

 

[coblerx4]

I read on Marine depot that the 10,000 last 2 years and Atinic 18 months.

 

[rockdog]

book is 18 months, I would shoot for every year also... if you see a color change it may be time then..

Jason

 

[wmboots]

I sell t-5 lighting to customers of my company for their warehouses and during the sale I let them know that t-5 lamps have an estimated 20,000 hour lamp life and from what I read about 10k and actinic lamps they have a 10,000 hour half life which to me would mean it would be about time to replace at 10,000 hours. How many months that is depends on the hours you have them burning per day.

 

[stickx911]

wmboots;289642 wrote: I sell t-5 lighting to customers of my company for their warehouses and during the sale I let them know that t-5 lamps have an estimated 20,000 hour lamp life and from what I read about 10k and actinic lamps they have a 10,000 hour half life which to me would mean it would be about time to replace at 10,000 hours. How many months that is depends on the hours you have them burning per day.

but light intensity would fall long before that 10,000 hours (@8 hrs a day would = about 1,250 days ~3.5 years)

 

[stickx911]

And I'm asking, not saying, wouldn't the bulb loose a good bit of brightness before 10,000 hrs?

 

[coblerx4]

I thought that was what was great about T5's that they also stayed brighter longer? So it sounds like what I read that they should be changed at 1 1/2 and 2 years will be right if you account for any fading.

 

[wmboots]

I have a customer that we replaced all his old T-12 fixtures in his office area with T-8's over 2 years ago. While visiting him a couple months back to go over his request to change out some metal halides to T-5's in his warehouse he made the comment that he felt the lights in his personal office seem to be getting dimmer. I got my par meter out and was able to show him that after 2 years his T-8's were still putting out nearly the same as when we first installed them. The dimmished par was less than 1%. Having said this I believe if from what I have read and what I seen with T-5's I personaly believe you could easily go 18 months between bulb changes. I plan on installing a 6 lamp T-5 next time I have to place an order for a customer. Then I will just go by and see Sal or C.R. (depends on who gets me the best price) for lamps.

 

[dave]

Here is a good site about lighting. It's from 2002 but should still be valid.