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LED Bulbs
Where the LED bulb is used will effect the life time
http://www.ledsmagazine.com/article...n-fixture-type-and-usage-scenario.htmlMICHAEL KACHALA, director of engineering at Hinkley Lighting, explains that consumers need data on LED lamp life expectancy in specific application scenarios.
Rarely does "always" or "never" constitute valid advice. An elder may have shared, "Never stick your finger in an empty light socket; you must always assume the electricity is on." Bring that uncertainty forward to the life and reliability of an LED lamp in an Edison socket. I believe the industry in making lamps look like their incandescent grandparent is falsely addressing limits on LED adoption. The assumption is that you can always consider using the LED in place of incandescent. Yet the only warning we have is to never use most available lamps in an enclosed fixture.
Consider for a moment the ecological predecessor of the LED lamp ? the CFL. Has it become common knowledge among consumers that CFLs will not perform as claimed in some fixture applications? Whose responsibility is it to make them aware of these limitations? Is it the belief that LED will overcome CFL's inherent shortcomings? In fact, LED lamps can and do fail even sooner and of course at higher fiscal cost.
I had the opportunity to share these thoughts with an engineer from a lamp manufacturer. He acknowledged that the lamp manufacturers have known for years that when CFLs are placed in the socket-up position, they last an average of 3,000 hours. Yet despite this knowledge, the package declaration to consumers only states 12,000 hours as the life expectancy. Our government regulates the packaging information.
While expanding our GU24-socket fixture product offerings, we undertook testing to determine the maximum CFL wattage as required by UL. Knowing a lamp consumes less power and thus produces less light while operating at higher temperatures, we measured CFL ballast enclosure temperatures as directed by lamp manufacturers.
After compiling results of different lamp brands, our findings indicated CFLs needed at least 20 in.3/W in enclosed lighting chamber volume, such as a typical ceiling flush mount. For example, a dual 13W CFL lamp would meet stated life in an 18-in. diameter bowl fixture. A dual 60W incandescent fixture could be as small as 13 in. Semi-enclosed fixtures depended upon lamp up or down and how close the glass shade was to the lamp. Interestingly, we also learned that the majority of CFLs quickly reduced power attaining a typical 70% level of stated light output.
Our lab attempted similar testing for LED lamps. With the exception of a single lamp brand with specs on use in enclosures, no other lamp manufacturer had temperature data to share with us. We learned that no standards exist to test and provide this information, more so that the LED lamp is considered an isolated thermal plane and not considered to dissipate heat into the fixture. To further complicate matters, some manufacturers shared that the ceramic paint covering the metal heat sink or plastic enclosure surrounding the driver is applied that way in part for product safety. It seems that consumers understand not to touch an operating incandescent lamp with a bare hand, but since CFLs are cooler, LED lamps must also remain cool enough to touch.
Electronics folks know there are no new technical breakthroughs in thermal management. The latest LED lamps run electronics hotter than their predecessors and drivers can fail quickly from de-soldering or thermal breakdown of components.
Energy Star long-term testing for LED lamps occurs with 40?C degree air surrounding the lamp, and not in typical fixtures. We find in our 25?C temperature-controlled test lab that the lighting chambers of semi-enclosed wall sconces regularly exceed 60?C with 8W lamps. Enclosed multi-lamp ceiling fixtures can exceed 90?C. So what are the impacts to anticipated life because of elevated operating temperature?
Insiders may know that Energy Star attempted to address testing temperature in the recent revision of the standard. Presumably, utilities shot down any testing change. The market desire and dynamics to adopt energy-saving technology have inertia in the form of rebates the utilities are compelled to apply. And the recent proposal to change testing standards by the US Department of Energy does not revise the 40?C test, nor address any aspect of varying lamp applications.
The general public needs a range of life expectancy as the lamp is used by the consumer. We have to move beyond the never and always paradigm, or we risk having LED technology disappoint the buying public more than CFLs have.
http://www.ledsmagazine.com/article...n-fixture-type-and-usage-scenario.htmlMICHAEL KACHALA, director of engineering at Hinkley Lighting, explains that consumers need data on LED lamp life expectancy in specific application scenarios.
Rarely does "always" or "never" constitute valid advice. An elder may have shared, "Never stick your finger in an empty light socket; you must always assume the electricity is on." Bring that uncertainty forward to the life and reliability of an LED lamp in an Edison socket. I believe the industry in making lamps look like their incandescent grandparent is falsely addressing limits on LED adoption. The assumption is that you can always consider using the LED in place of incandescent. Yet the only warning we have is to never use most available lamps in an enclosed fixture.
Consider for a moment the ecological predecessor of the LED lamp ? the CFL. Has it become common knowledge among consumers that CFLs will not perform as claimed in some fixture applications? Whose responsibility is it to make them aware of these limitations? Is it the belief that LED will overcome CFL's inherent shortcomings? In fact, LED lamps can and do fail even sooner and of course at higher fiscal cost.
I had the opportunity to share these thoughts with an engineer from a lamp manufacturer. He acknowledged that the lamp manufacturers have known for years that when CFLs are placed in the socket-up position, they last an average of 3,000 hours. Yet despite this knowledge, the package declaration to consumers only states 12,000 hours as the life expectancy. Our government regulates the packaging information.
While expanding our GU24-socket fixture product offerings, we undertook testing to determine the maximum CFL wattage as required by UL. Knowing a lamp consumes less power and thus produces less light while operating at higher temperatures, we measured CFL ballast enclosure temperatures as directed by lamp manufacturers.
After compiling results of different lamp brands, our findings indicated CFLs needed at least 20 in.3/W in enclosed lighting chamber volume, such as a typical ceiling flush mount. For example, a dual 13W CFL lamp would meet stated life in an 18-in. diameter bowl fixture. A dual 60W incandescent fixture could be as small as 13 in. Semi-enclosed fixtures depended upon lamp up or down and how close the glass shade was to the lamp. Interestingly, we also learned that the majority of CFLs quickly reduced power attaining a typical 70% level of stated light output.
Our lab attempted similar testing for LED lamps. With the exception of a single lamp brand with specs on use in enclosures, no other lamp manufacturer had temperature data to share with us. We learned that no standards exist to test and provide this information, more so that the LED lamp is considered an isolated thermal plane and not considered to dissipate heat into the fixture. To further complicate matters, some manufacturers shared that the ceramic paint covering the metal heat sink or plastic enclosure surrounding the driver is applied that way in part for product safety. It seems that consumers understand not to touch an operating incandescent lamp with a bare hand, but since CFLs are cooler, LED lamps must also remain cool enough to touch.
Electronics folks know there are no new technical breakthroughs in thermal management. The latest LED lamps run electronics hotter than their predecessors and drivers can fail quickly from de-soldering or thermal breakdown of components.
Energy Star long-term testing for LED lamps occurs with 40?C degree air surrounding the lamp, and not in typical fixtures. We find in our 25?C temperature-controlled test lab that the lighting chambers of semi-enclosed wall sconces regularly exceed 60?C with 8W lamps. Enclosed multi-lamp ceiling fixtures can exceed 90?C. So what are the impacts to anticipated life because of elevated operating temperature?
Insiders may know that Energy Star attempted to address testing temperature in the recent revision of the standard. Presumably, utilities shot down any testing change. The market desire and dynamics to adopt energy-saving technology have inertia in the form of rebates the utilities are compelled to apply. And the recent proposal to change testing standards by the US Department of Energy does not revise the 40?C test, nor address any aspect of varying lamp applications.
The general public needs a range of life expectancy as the lamp is used by the consumer. We have to move beyond the never and always paradigm, or we risk having LED technology disappoint the buying public more than CFLs have.
LEDs def have an upper limit on wattage due to heat dissipation. Too big and they have mini fans built in, which is just too complicated. They've been getting around it by using many small bulbs instead a few large bulbs, such as you see on car brake lights. A huge breakthrough with come when they become cost competitive with four ft fluorescent tubes. They can be retrofitted into old fixtures, but it requires some tweaking. Four and eight ft bulbs need regular replacement along with their ballast resistors, and one advantage of LEDs is low maintenance. In industrial settings, the lights are often over 20ft overhead and the labor costs for fluorescent maintenance can add up. I've seen the LED replacement drop in price by half, but they can be hard to source.
We switched our big Ford E350 van to LED headlights, at the suggestion of our trusted mechanic. So far we really like them, but admit they look a tad weird.
The lows and highs are aimed slightly differently.
Off:
On:
High Beam (which are plenty bright):
I forget the price, but they weren't that spendy.
The lows and highs are aimed slightly differently.
Off:
On:
High Beam (which are plenty bright):
I forget the price, but they weren't that spendy.
Whoa? I replaced several CFL's 100 W for 100 W LED outdoor flood lights. An amazing difference. "I can see clearly now" is an understatement.
I have not measured my amp difference but I have no problem with my visual security. Being new I have no input on how long they will last.
These are the simple screw in bulbs for regular outdoor spot/flood units that most are used to. I did buy ONE FANCY unit that does fine not worth the money when I can just change our a screw in light bulb.
I really don't care what some people wish to argue. Windygey has his own views and that's just fine. Others march on. LOL
I have not measured my amp difference but I have no problem with my visual security. Being new I have no input on how long they will last.
These are the simple screw in bulbs for regular outdoor spot/flood units that most are used to. I did buy ONE FANCY unit that does fine not worth the money when I can just change our a screw in light bulb.
I really don't care what some people wish to argue. Windygey has his own views and that's just fine. Others march on. LOL
My interest is that people march on with the best information available. The DR can be a toxic place for electronics. An LED is a basic electronic device prone to different failure modes from other light emitting technologies. Talk to those who live near the ocean and have precious computers eaten by the salt in short order. Or on a grid where the power has large spikes, or is either too low or too hight in voltage. Some electronics does not like the "modified sine wave" output of most inverters used here (my Lutron LED dimmers paired with dimmable LED bulbs being one example). A bulb without the proper cooling may have great light output for a short life time.
Being an electronics engineer myself, I like to find out as much as I can what the problems versus the benefits are for technologies. I think of it as an on going discussion over time and not an argument.
Being an electronics engineer myself, I like to find out as much as I can what the problems versus the benefits are for technologies. I think of it as an on going discussion over time and not an argument.
Yachts have two completely separate electrical systems. One for 120v and one for 12vdc. Inverters on a yacht are a totally different animal than what is usually sold for house systems in that they automatically come on when there is no shore power or other 120v service feeding into the system and switch to charging mode complete with deep and float charging capabilities when AC is connected to them. Also you are correct in that most new inverters are over 90% efficient with exception of the older "modified sine wave" inverters. Not only is proper wire size from the solar panels to the charge controller and onto the batteries important (better to be too big than too small), but so is the wire diameter. Many small strands will create a better electrical highway than will fewer larger wire strands for the same overall sized wire. Also tinned marine cable will last much longer in Caribbean conditions.*
There are several LED sites available and it's best if one takes their time to understand what it is that they are buying beforehand. I've thrown a few hundred dollars away before finding proper working LED Lights. Now our yacht is all LED inside and out greatly reducing our overall power consumption which is important when living solely off.of solar and wind. I use superbright LED.*
www.superbrightled.com
Exactly why I exercise caution when jumping into a technology.
As for wire given wire guage and the amount of wire strands for that given guage having an effect on energy loss, where do you have proof for that? (Of course different guages will have different current carrying ability, but unless we are getting into the skin effect at very high voltages, I would like to see the reason why the number of strands makes a difference for DC or AC voltages up to 220V used commonly in a home). I understand that when very high currents are used, finely stranded wire can be of some help, but it generally is not an issue in home wiring.
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I agree. *Wire strand size has no effect on conductivity. As a general rule the gauge of the wire (i.e. the cross section area of the conductor) is determined by the current the the cable is required to carry at its maximum load plus 20%*
The thickness of the insulation is determined by the voltage the cable is required to carry.
The only beneficial factor in having multi-strand wires is so that the wire can withstand bending, flexing, vibration etc. *Household wiring is not required to flex, so multi-strand wire is not important.
Have you never heard of a little thing *called resistance winde?? Just like more cars can travel faster in five lanes than four, electricity can travel faster (less resistance) with more strands than a few thick ones.http://electronics.stackexchange.co...oes-the-thickness-of-a-wire-affect-resistance
Basic engineering rules..
The link you provided shows the property of resistance based upon a smaller wire having more resistance. Basic electrical engineering indeed and you have clearly misunderstood its intent. The overall wire guage is by far and away the determining factor for its resistance for house hold wiring and not the number of conductors used.
beeza has responded correctly about this point in post 71. Multistranded wires are used where flexibility and heat dissipation are needed at lower voltages.
The skin effect and the use of more strands to carry more current is important at higher voltages like those used in AC power transmission lines.
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Sure winde.. The whatever you say. People putting together solar systems had better understand that DC Voltage is way different than AC. Go cheap, and you will have cheap. Especially when it comes to wire type, and size. Multi strand tinned wire is the way to go if one wishes to get maximum results from their solar systems. Problem is that multi strand tinned wire is twice the cost. Some think that it doesn't matter but it does.. Just ask anyone who lives abord and depends on their alternative energy source for power. I highly suggest people educate themselves on DC voltage before going to solar or wind power. I pulled the first link that came up winde, but I know what I know, and you should take a look at multi wire vs large strands and the resistance between the two.. Big difference and it's not my rules.. I didn't come up with physics laws.
To be clear, I am talking about AC voltage and the importance of the skin effect for the most part.
Regarding DC applications like boats or solar panels, they are in potentially wet or humid environments, the tinned wire provides much greater "resistance" to corrosion. In other words, tinned copper will last much longer.
Having more strands to the wire could be useful in dissipating heat and certainly in flexiblity, but it is not going to lower the wires DC resistance at a given wire gauge. In fact, if there is less copper in the cross sectional area of the multistranded wire than in a solid wire, the multistranded wire will carry LESS DC current . That is basic electrical engineering.
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