More LED bulb options

[tmbrown97]

I'm going to ask a dumb question here - but Inrush is just a minimal momentary thing - even a 15A breaker will absorb 20A for a split second, right?  Many of the ratings on switches are related to sustained dimming due to heating up the switch and everything in it - but is that seriously an issue for that millisecond when things kick on?  A switch that's rated for 900W is really only creating heat while dimming, isn't it?  I mean when it just kicks the whole load on, it isn't really creating that heat, unless I'm mistaken.  
 
I was under the impression that those ratings were about worst case scenario - running 900W worth of bulbs at maximum dimming so the switch is putting out it's maximum amount of heat... that's a whole different type of failure than a wire carrying a little extra juice for a split second, but well within its rating.
 
I have absolutely ZERO concern about Inrush unless I find it's causing my switches to malfunction - but hey, maybe I'm the one being naive.  If a switch blows up and shoots sparks, I can deal with that instantly - I'm 10,000x more concerned about something like a switch that's overheating and cooking over 3 hours and finally sparking a fire in my Dining Room after all my guests and I have migrated to another room than a momentary condition.  
 
And I don't know if this hurts or helps, but all of my switches ramp, albeit quickly - so I'd really like to know the effect that has on inrush since they don't just get flipped on - they dim up over like 1.3 seconds or even .06.

 

[Waynedb]

I'm going to ask a dumb question here - but Inrush is just a minimal momentary thing - even a 15A breaker will absorb 20A for a split second, right?  Many of the ratings on switches are related to sustained dimming due to heating up the switch and everything in it - but is that seriously an issue for that millisecond when things kick on?  A switch that's rated for 900W is really only creating heat while dimming, isn't it?  I mean when it just kicks the whole load on, it isn't really creating that heat, unless I'm mistaken.  
 
I was under the impression that those ratings were about worst case scenario - running 900W worth of bulbs at maximum dimming so the switch is putting out it's maximum amount of heat... that's a whole different type of failure than a wire carrying a little extra juice for a split second, but well within its rating.
 
I have absolutely ZERO concern about Inrush unless I find it's causing my switches to malfunction - but hey, maybe I'm the one being naive.  If a switch blows up and shoots sparks, I can deal with that instantly - I'm 10,000x more concerned about something like a switch that's overheating and cooking over 3 hours and finally sparking a fire in my Dining Room after all my guests and I have migrated to another room than a momentary condition.  
 
And I don't know if this hurts or helps, but all of my switches ramp, albeit quickly - so I'd really like to know the effect that has on inrush since they don't just get flipped on - they dim up over like 1.3 seconds or even .06.

Here is some info I found.
http://www.lrc.rpi.edu/programs/solidstate/assist/pdf/ASSIST-TechNote-Dimming-InrushCurrent.pdf

 

[BLH]

Many LED bulb manufactures will have data on their web site for the incandescent equivalent for their bulbs. When calculating how many on a dimmer.
One of my LED bulb say. Use an 80 watt value when calculating total wattage on a dimmer.
The repetitive peek currents also have to be taken into consideration. As pointed out in the above link.

 

[apostolakisl]

I'm going to ask a dumb question here - but Inrush is just a minimal momentary thing - even a 15A breaker will absorb 20A for a split second, right?  Many of the ratings on switches are related to sustained dimming due to heating up the switch and everything in it - but is that seriously an issue for that millisecond when things kick on?  A switch that's rated for 900W is really only creating heat while dimming, isn't it?  I mean when it just kicks the whole load on, it isn't really creating that heat, unless I'm mistaken.  
 
I was under the impression that those ratings were about worst case scenario - running 900W worth of bulbs at maximum dimming so the switch is putting out it's maximum amount of heat... that's a whole different type of failure than a wire carrying a little extra juice for a split second, but well within its rating.
 
I have absolutely ZERO concern about Inrush unless I find it's causing my switches to malfunction - but hey, maybe I'm the one being naive.  If a switch blows up and shoots sparks, I can deal with that instantly - I'm 10,000x more concerned about something like a switch that's overheating and cooking over 3 hours and finally sparking a fire in my Dining Room after all my guests and I have migrated to another room than a momentary condition.  
 
And I don't know if this hurts or helps, but all of my switches ramp, albeit quickly - so I'd really like to know the effect that has on inrush since they don't just get flipped on - they dim up over like 1.3 seconds or even .06.

 
My understanding of a triac dimmer is such that I do not believe heat dissipation at the dimmer is significantly different at different percentage levels of on.  The triac uses gating, not resistance to alter the current to the load.  Correct me if I am wrong on this.
 
That is an interesting article regarding the repetitive inflow issue with triac dimmers.  Since the triac is using gating to control current, it is like you are turning the device on 120 times per second.  I would think better quality LED's would use capacitors and/or other electronics to smooth that out though.  This would seem to have the potential to be worse at the most dimmed levels since the gate is closed longer allowing the LED to discharge itself the most in between pulses and act like a truly off bulb at each new pulse.

 

[tmbrown97]

That's why I asked  :blink:
 
Now to set up a test bench for LED bulbs...

 

[etc6849]

That makes two of us!  I only have an old analog oscilloscope, so I have no way to record transient current (yet).
 
However, I just bought one of these guys:  http://www.tequipment.net/RigolDS2072.html
 
I didn't just buy it for light bulb testing, so this isn't the solution for everyone in this thread, but thought I'd share.  The DS2000 series can do all sorts of neat things like serial decoding too.  In general, the Rigol scopes are very hackable.  With the DS2072, I'll end up with a $1699 scope + $778 options for only $788 (after 6% eevblog discount).  The DS4000 series can be hacked in a similar fashion too, but the cost of the 4000 series was too high for me to justify as a hobbyist.
 
Of course, once I set it up, if anyone wants to send me some led lamps for free, I'd be happy to post screen shots of the current transients.
 
PS Work2Play:
I just read your other post.  I think some of the nicer Fluke amp probes have an inrush option. However, if the sampling frequency is slow (which is probably the case), you could easily miss the peak, so you can't use any of your existing gear to measure inrush current.  
 
In short, you should look for a cheap digital oscilloscope.  The Rigol DS1052 is a more affordable option than the DS2072 I bought, but really it's worth the extra price for a much nicer scope (IMHO).  Hears a video comparing the two:  http://www.youtube.com/watch?v=_TSr9nFN1GU

 

[etc6849]

I believe anytime you use a piece of equipment outside its design, one invalidates that equipment's UL listing?  However, I'll admit, I could be overly paranoid about inrush current.  I haven't actually bought any LED lamps yet, but since I want lamps brighter than 60 watts, I'll have to look at other options than traditional incandescent lamps (including the overly priced halogen lamps).  
 
I'm also paranoid about using an A21 lamp in an A19 enclosed fixture.  I think that would also invalidate the fixtures UL listing.  I guess that means I'll never get to have 1600 lumens out of single lamp fixtures again...?!?
 
This brings up an important question: if you really use these lamps with fixtures and dimmers not designed for them and your house burns down, is your insurance going to pay out or are they going to cry foul?
 
I really wish the government would solve bigger problems instead of sticking their nose where it doesn't belong...  It simply isn't worth risking fire to my home or ruining $70+ dimmers to save a few dollars/year.  Maybe they'll undue the ban as more and more try CFLs and realize how crappy they are (and how overly priced LED lamps are).  Regardless, I'm not a happy camper right now.

 

[etc6849]

I think this is how most modern dimmers work.  There wouldn't be any energy savings if they used resistance.
 

The triac uses gating, not resistance to alter the current to the load.  Correct me if I am wrong on this.

 

[apostolakisl]

I believe anytime you use a piece of equipment outside its design, one invalidates that equipment's UL listing?  However, I'll admit, I could be overly paranoid about inrush current.  I haven't actually bought any LED lamps yet, but since I want lamps brighter than 60 watts, I'll have to look at other options than traditional incandescent lamps (including the overly priced halogen lamps).  
 
I'm also paranoid about using an A21 lamp in an A19 enclosed fixture.  I think that would also invalidate the fixtures UL listing.  I guess that means I'll never get to have 1600 lumens out of single lamp fixtures again...?!?
 
This brings up an important question: if you really use these lamps with fixtures and dimmers not designed for them and your house burns down, is your insurance going to pay out or are they going to cry foul?
 
I really wish the government would solve bigger problems instead of sticking their nose where it doesn't belong...  It simply isn't worth risking fire to my home or ruining $70+ dimmers to save a few dollars/year.  Maybe they'll undue the ban as more and more try CFLs and realize how crappy they are (and how overly priced LED lamps are).  Regardless, I'm not a happy camper right now.

 
1) I'm totally with you on the government thing.  The gov't ban on incandescent bulbs is absurd.
2) I don't agree with you on the belief that LED's are overpriced.  For your most commonly used fixtures (4 hours per day), the payback on the Cree A19 bulb is around 1.5 years at .13/kwh electricity.  The bulb should last you at least 10 times that long, so it is makes perfect sense.  The CR6 bulb payback is about 4 years.  That doesn't include the savings if you live in a hot climate regarding less heat.  And the new BR30 bulb would be around 2 or 3 years.
 
For rarely used bulbs, we should be using 50c incandescent bulbs.  Like that attic light that is on 5 minutes per year.  The government's ban is just dumb.  The payback on that is like forever.
 
The market has and will continue to drive companies like Cree to develop better LED bulbs all the time.  The government's role, as usual, distorts markets and almost always creates unintended outcomes and generally someone who is politically connected manages to profit from it.
 
I don't think there are any insurance issues to be had with bulbs like the Cree ones.  They are UL listed dimmable bulbs.  UL would not put their stamp on them with that language if they couldn't be used with standard dimmers.  Plus, I have about 40 of them (CR6) in my house on Insteon dimmers without even a hint of trouble.

 

[Automate]

Incandescent bulbs will have a higher inrush current also.  Metals have higher resistance at higher temperatures.  An incandescent bulb will draw its rated current when the filament is already white hot.  When you first turn on the bulb and the filament is at room temperature it will have less resistance and therefore higher current draw.

 

[Waynedb]

 
I really wish the government would solve bigger problems instead of sticking their nose where it doesn't belong...  It simply isn't worth risking fire to my home or ruining $70+ dimmers to save a few dollars/year.  Maybe they'll undue the ban as more and more try CFLs and realize how crappy they are (and how overly priced LED lamps are).  Regardless, I'm not a happy camper right now.

Maybe I am just crazy but I don't see what the big deal is about the standard incandescents not being for sale anymore, you can buy halogen bulbs that look the same, are just as bright and use less power than a standard incandescent and they are not expensive. Who cares if a 100 watt bulb isn't available when a 72 watt bulb is for all intents and purposes just as good and barely cost any more.

I use L.E.D. Lights because electricity in California is very expensive ever since the manufactured shortages we had where utilities were purposely shutting down power plants to drive up electric rates, we also had companies selling natural gas charging 9 times as much to send it out here versus the east coast. Now in California we have tiered electric rates where the top tiers include an arm and a leg in the price.

 

[tmbrown97]

I think it depends on where we live - with $.35/kWh (my current rate), I like LED bulbs because the payback is pretty quick for me; I couldn't care less about Incandescents being gone, although I agree that the government should stay the hell out of it.
 
ETC - I'm very curious about the scope and what you mean by "hackable" - I do a lot of microwave work and scopes are definitely used in that work but I have never learned that aspect myself...  while not in the cards in the short term, I could see buying one of these down the road.

 

[etc6849]

Halogen lamps are much more expensive than incandescent as far as a percentage of initial cost.  I remember getting a 100W incandescent for $.5/lamp versus $1.5 to $2.50/lamp for halogen.  Further I put 6 60 watt equivalent halogen lamps on a 600w Leviton dimmer and the dimmer quit working after a year!  It could have been coincidence, but I'm going to measure some halogen lamps when my digital oscilloscope shows up.
 
My complaint (more like a statement of fact) is now I have less options as a consumer.  Whatever happened to letting folks decide what products to buy on their own?!?  The truth about the light bulb ban is manufacturers wanted to have a reason to charge more, and our government wants to dictate how we live and what products we buy and use (and of course get donations from the manufacturers).  It's not like our government has bigger problems to solve or anything...
 
LED lamps are expensive in that you know in five years or less, new and better versions will be half the cost or even less of what you pay!  The $30 100w equivalent LED lamps today will be $5 in the near future.  Is it really worth investing in LEDs now, when I know for sure prices for the technology will fall even more and better options will be available?  Not to mention using LED lamps could ruin expensive dimmers or burn down my home, wiping out any cost savings.  I don't care what your electric bill is, if you fry a $70+ dimmer, you will lose money.
 
Sure there's a positive NPV (net present value) if I switch to LEDs and keep the same lamps for 5 years (duh).  But what better options and price drops will I miss out on if I buy now?  How much more money would I have saved had I waited a year or two before switching?  There is an opportunity cost with any new technology that can't be ignored.

 

[etc6849]

In the case of the scopes I linked to hackable means enabling extra features:
RS232, i2c, SPI serial decoding,
increasing memory depth: the available number of points stored for a trigger (56 Mpts from 14 Mpts) and 
increasing the bandwidth (e,g, from 70MHz to 200MHz for the DS2000 series)
 
Within a series, most of the Rigol scopes have software limitations, but the same hardware.  There's no soldering involved and the hacks get simpler every day.  The thread on hacking them is here:  http://www.eevblog.com/forum/testgear/sniffing-the-rigol's-internal-i2c-bus/585/
 
I probably won't risk hacking mine until I actually need one of the extra features.  If you buy one of the Rigol scopes, I wouldn't update the firmware before reading the above thread as the manufacturer can fix the vulnerabilities at any point.
 
PS:  electric rates are less than $.12/kwh for me.  I can't imagine paying the electric bill you are potentially talking about!
 

I think it depends on where we live - with $.35/kWh (my current rate), I like LED bulbs because the payback is pretty quick for me; I couldn't care less about Incandescents being gone, although I agree that the government should stay the hell out of it.
 
ETC - I'm very curious about the scope and what you mean by "hackable" - I do a lot of microwave work and scopes are definitely used in that work but I have never learned that aspect myself...  while not in the cards in the short term, I could see buying one of these down the road.

 

[etc6849]

The problem isn't the UL listed LED lamps (Cree appears to be an excellent brand from what I've read).  It's using a dimmer that the manufacturer clearly says is not for LED lamps.  To my knowledge this would invalidate the UL listing of that dimmer (and perhaps for the fixture too if it wasn't designed for the particular bulb shape).  That said, I'm not too worried if I hear more success stories like yours after years of use...
 

I don't think there are any insurance issues to be had with bulbs like the Cree ones.  They are UL listed dimmable bulbs.  UL would not put their stamp on them with that language if they couldn't be used with standard dimmers.  Plus, I have about 40 of them (CR6) in my house on Insteon dimmers without even a hint of trouble.