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Discussion Starter · #1 ·
So here's the situation. I installed 91 pendant lights rated for 100-150 watt halogens in my churches sanctuary. It was a renovation job, and we added 2 wings on either side of our main sanctuary. I installed the wiring in 3/4" conduit and ran #10 thhn solid from the dimming panel to the first light, and then #12 from that point to the rest of the fixtures (10 total per dimming channel/ckt). I installed 3 ckt's + ground (6 total current carrying conductors) per conduit run. Every splice is twisted properly then wirenutted. Being this is the church I attend, I made sure everything was done correctly by doing it myself instead of having any of my apprentices do it.

Now the problem. In the main sanctuary and the right wing, I ran all new wiring from the dimmer panel to the fixtures. In the left wing I reused existing piping and wiring from the dimmer panel to a JB in a mechanical room where I picked up the circuitry and wired the lights in that wing. The wire size was #12 stranded in the reused pipe. I calculated the voltage drop before I decided to reuse it and determined it was well within my 3% drop allowance. Since all the lights have been installed I've had 31 go out randomly within a 2 month time period. No bulbs burned out in the left wing yet, only the main sanctuary and right wing. I checked connections just to verify my workmanship and everything checked out fine. When checking voltage (my source voltage is 119 at dimming panel), I found that in the left wing (the one I used existing wiring) that when under load the end of line voltage is 114v. The main sanctuary and right wing she under load have 118v. The bulbs are Feit par 38 86watt 120volt indoor outdoor floods. I know they're not the greatest bulbs, boss is cheap. So I'm thinking that the reason the left wing isn't burning out bulbs is because of the voltage drop, and that if I used 130 volt bulbs in the main sanctuary and right wing, I won't have bulbs burning out every few weeks.

Has anyone else ever had this problem with these type of bulbs? Any suggestions? One more thing, I used 130v 100watt bulbs in temp pigtail lights on all this wiring between Christmas and end of March until my lights arrived. I only had maybe 8 bulbs burn out in this time, mostly towards the end, and the lights were on everyday for construction purposes. Thanks for reading and I'm anxious to get your feed back!
 

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We'd all like to believe that a light bulb is just a light bulb (or, more properly, a "lamp" :laughing: ). Most electricians have come to the conclusion, however, that there's a great disparity between brands in terms of how long they last. There's also an outside chance that the dimming controls or DMX unit or whatever you have is using a MWBC and has the neutral gone marginal someplace. Given that you note the budget brand lamps used, I think this is the beginning and end of your issues.
 

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Discussion Starter · #7 ·
Yes I agree Feit is junk, but 24 Feit bulbs have not burned out at all in the left wing, where my voltage is 114v. However 31 out of 67 have burned out in the other 2 areas where my voltage is 118.6v to be exact. Am I crazy or am I on to something regarding the voltage of the bulbs rating(120) being fine at 114v but the ones at 118.6 are going out prematurely would be better suited with a 130v rated bulb.

I'm considering putting 2 130v bulbs and 3 120v bulbs in the same row right out of the box, and seeing which ones last longer.
 

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Yes I agree Feit is junk, but 24 Feit bulbs have not burned out at all in the left wing, where my voltage is 114v. However 31 out of 67 have burned out in the other 2 areas where my voltage is 118.6v to be exact. Am I crazy or am I on to something regarding the voltage of the bulbs rating(120) being fine at 114v but the ones at 118.6 are going out prematurely would be better suited with a 130v rated bulb.

I'm considering putting 2 130v bulbs and 3 120v bulbs in the same row right out of the box, and seeing which ones last longer.
Fantastic. You do your mad scientist experiment, then go watch Myth Busters. The rest of us already figured it out for you. :laughing:
 

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Discussion Starter · #11 ·
Fantastic. You do your mad scientist experiment, then go watch Myth Busters. The rest of us already figured it out for you. :laughing:
Thanks I appreciate the sarcasm...but I'm looking for the reason. The 24 lights in the section that has 114 v hasn't had a bulb burn yet while 31 others did in a section with a slightly higher voltage has. I don't want my co or the church to spend $ ,by a different brand bulb, and have the problem reoccur on the same fashion. Verify the problem to better the solution.
 

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Thanks I appreciate the sarcasm...but I'm looking for the reason. The 24 lights in the section that has 114 v hasn't had a bulb burn yet while 31 others did in a section with a slightly higher voltage has. I don't want my co or the church to spend $ ,by a different brand bulb, and have the problem reoccur on the same fashion. Verify the problem to better the solution.
Your problem has been verified. Cheap lamps don't last as long. Several actual electricians have told you that. It necessarily stands to reason that the closer the voltage provided is to the lamp's rating, so much the shorter life you'll realize. Of course changing to 130v lamps will make them last longer. That's what math people call a "given". :thumbsup: Programming your dimming unit to make 100% actually 90% will have the same effect.
 

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Getting good quality incandesant lamps is very difficult now days !
Since the beginning of the phase out of theses lamps
the amount sold has dropped dramatically, so the majors are
simply not interested in making high quality lamps any more.
Most are sourced from china, even the majors have there lamps
made there now, so quality is a joke.
Get used to it as it will only get worse.
look for long life lamps
2500 hrs instead of 1000hrs.
 

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I don't know if this works for halogens to but for compact fluorescent they need to run 100 hours 100% after install before dimming them. Are they ballasted halogen bulbs?

Also why not go with LED? You might even get rebate from energy company from 50% to 90% rebate depends what programs you got.
 

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I'll play:

If I've got the right lamp, this thing is rated for 41 days. Without knowing how much they're being used, let's pretend in the Left Wing you're seeing a 50% reduction in life.

I can't swear this is true for halogens, but just about every curve I find for tungsten elements equates a 5% overvoltage to a 50% reduction in lamp life.


If the "good" circuit is 114 volts, what's 105% of that? 119V, which coincidentally, is just about what voltage you've got on your Left Wing circuit.

Besides which, if I remember right, lamp life is rated on the number of hours it takes 50% of a test batch to burn out. So even if these weren't crap lamps, it still doesn't mean that any given lamp is guaranteed to not burn out before that mark.
 

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Seriously, it's because they're FEIT.

Menards sells FEIT and they're often on clearance so I have tried TONS of FEIT. Halogen PARs, CFLs, CFL PARs, LED PARs. I have had no issues with their LEDs. I've had a handful of CFL and CFL PAR failures, maybe 10%, which is the same as any offbrand CFLs.

We installed maybe 20? recessed cans in our banquet room about a year ago. I put in about half 90w FEIT PAR38s, half Sylvania 80w PAR38s. *ALL* of the FEIT bulbs died in the first few months. *ALL* of the original Sylvania bulbs are still working.

If your boss is cheap? Bulbrite. Or, whatever offbrand 1000bulbs.com sells. I've have great experiences with both.
 

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Discussion Starter · #20 ·
I appreciate the helpful advice. dspiffy, your banquet hall scenario was very helpful to use as a reference to back up why Feit bulbs are junk.

I came here for professional, experienced knowledge, and I thank all of you who posted. I'm 39 and the master in the company I work for. I have 16 years experience and I know I don't have all the answers. There's no one older or with more experience than me that I can go to in my company for more complex problems. Is there a section of this Forum that discusses trouble shooting issues? I like to learn from others every chance I get, and in my position now, everyone looks to me for answers. I've been around and seen what I've seen, but there's so much more out there. Thanks again!
 
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