Solar Question(s) Please Help

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williaty
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Re: Solar Question(s) Please Help

Post by williaty » Thu Sep 26, 2013 4:09 pm

teotwaki wrote:Go read the manual at http://www.xantrex.com/documents/Power- ... 0-5000.pdf" onclick="window.open(this.href);return false;. Given that this is factory literature from a top brand company, tell me what you "literally believe" after you read "No load current draw < 0.3 A DC" in the specs on page 2.
OK, I see why we're arguing now. You have a modified square wave inverter. Yeah, efficiency on those is considerably higher and base load is considerably lower all at the expense of not being able to safely power all kinds of devices. I have several things that refuse to run properly off a MSW inverter, so I am in the habit of thinking only in turns of pure sine wave inverters. So, yeah, I believe a MSW inverter has those specs, now that I know you're talking about a MSW inverter.
but all of the hand-waving, multiquotes and thousand word rebuttals don't bode too well for at least appearing reasonable. Lighten up man! Share knowledge but skip the lectures.
I find it extremely bewildering that you find giving a good answer to be a bad thing.
Speakin' of words "napping" must be = idle = standby but sadly there is no mysterious Xantrex "napping" mode that pulls less power than idle mode.
Depends on the brand and model. Amazingly enough, I didn't psychically know which inverter you had, so I was assuming you had a full-featured one. Some inverters have a partial power mode where they alter the shape of the output wave form to reduce the total power output during low-demand use while leaving full output voltage available to low-power use devices (such as a night light). Others have a mode where the inverter output shuts off for a couple of seconds at a time, then flicks on for a split second to see if a load has tried to switch on and, if it detects a load the inverter will then "wake up" and go to full power output. Some inverters have both functions. Your Xantrex has neither, which is probably why you aren't aware of it.

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Re: Solar Question(s) Please Help

Post by teotwaki » Thu Sep 26, 2013 5:55 pm

williaty wrote: OK, I see why we're arguing now. You have a modified square wave inverter. Yeah, efficiency on those is considerably higher and base load is considerably lower all at the expense of not being able to safely power all kinds of devices. I have several things that refuse to run properly off a MSW inverter, so I am in the habit of thinking only in turns of pure sine wave inverters. So, yeah, I believe a MSW inverter has those specs, now that I know you're talking about a MSW inverter.

I find it extremely bewildering that you find giving a good answer to be a bad thing.

Depends on the brand and model. Amazingly enough, I didn't psychically know which inverter you had, so I was assuming you had a full-featured one. Some inverters have a partial power mode where they alter the shape of the output wave form to reduce the total power output during low-demand use while leaving full output voltage available to low-power use devices (such as a night light). Others have a mode where the inverter output shuts off for a couple of seconds at a time, then flicks on for a split second to see if a load has tried to switch on and, if it detects a load the inverter will then "wake up" and go to full power output. Some inverters have both functions. Your Xantrex has neither, which is probably why you aren't aware of it.
Actually they are called "modified sine wave" (MSW) which I find to be a euphemism but what can you do with advertising anyhow..... "a square wave with a variable delay between polarity transitions" is a bit more complex than simply MSW.

And MSW does not magically make vague things like "sensitive electronics" expire. Please provide some specific citiations as I would appreciate them. The same spec sheet that I linked to says:

Product Applications
Household Appliances: compact microwave ovens, bread makers, food processors, small bar refrigerators,
small vacuum cleaners, fluorescent and incandescent lights, sewing machines and fans
Handheld Power Tools: drills, jigsaws, sanders and buffers
Entertainment Electronics: televisions, VCRs, video games, stereos, musical instruments and satellite equipment
Office Equipment: computers with 17” monitors, facsimile machines


Truly good answers, amazingly enough, are not defined by word count, number of syllables, acronyms or hyperbole. I appreciate this most recent effort to focus and pare down the bit torrent count :P

You did not know which inverter I had because you keep assuming. Ask questions once in a while then formulate an answer. The dialog is actually a good thing. :idea:

Again, assuming what I am and am not aware of and you provide no citations, links or references there is no telling what you may be talking about with non-industry terms like "napping" or a plethora of other assumptions based on you own home brew installation. Recall that there are interested parties reading this thread that are intelligent but unfamiliar with this topic and they would appreciate sources of information as well as plain spoken English so as to conduct their own research.
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Re: Solar Question(s) Please Help

Post by angelofwar » Thu Sep 26, 2013 7:11 pm

teotwaki wrote:The set up in my trailer's nose box with the 1500 watt inverter on the left
Image
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Awesome teotwawki!!! You build it yourself? Interested in those fuse boxes specifically. Got a link?
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Re: Solar Question(s) Please Help

Post by williaty » Thu Sep 26, 2013 8:33 pm

teotwaki wrote:Actually they are called "modified sine wave" (MSW) which I find to be a euphemism but what can you do with advertising anyhow..... "a square wave with a variable delay between polarity transitions" is a bit more complex than simply MSW.
I'm quite aware what the inverter makers claim their inverters are (modified sine wave). I'm also quite aware of what that waveform is called in every electrical engineering class I've ever take (modified square wave). The engineers acknowledge that the waveform in question has little to nothing in common with a pure sine wave and quite a lot in common with a square wave, so I call it what it is rather than lying and calling it a modified sine. I fully admit this isn't how the alt-e industry typically speaks, but I prefer scientific honesty to marketing lies.
And MSW does not magically make vague things like "sensitive electronics" expire. Please provide some specific citiations as I would appreciate them. The same spec sheet that I linked to says:
You're right, it won't flat out kill very many things at all. In fact, there's a LOT of stuff that works just fine with a MSW, or even square wave, inverter. There are a very few devices that will run too hot and fail if you run them at a high duty cycle. This is mainly a small subset of compressors and motors. One specific example, though, is that SWITCH brand lightbulbs will explicitly state that they're not compatible with MSW inverters if you email their tech support and get them to ask the engineering department. It causes the power supply to fail somehow (they wouldn't say how but I suspect it's due to the fact that the peak-to-peak voltage is different on MSW inverter than on pure sine and that the effective duty cycle is different). However, not being destroyed is not the same thing as working properly. There's two classes of devices that won't be harmed but will fail to work properly. The first is devices that use the zero-crossing of the voltage supply to determine timing. This means that some circuit design for clocks will fail to keep time properly. Remember that a clock can mean things that don't "tell time". A surprising number of things use clocks now to do internal timekeeping for various stages of their function. The second category is about half of all VSR (variable speed reversing) electric motors in tools and appliances. It seems there's two main topologies for a VSR circuit. One runs happily on a MSW inverter, the other doesn't work at all until you reach 100% output. My Milwaukee drill is one of the latter. If you start to pull the trigger when attached to a MSW inverter, nothing happens until you reach full throttle and then it'll suddenly kick on and run at full speed. Sometimes, it'll kind of jerk and shudder a few times if you hold it at part throttle, but it won't actually run. Note that the known problems with some VSR circuits and MSW inverters directly contradicts Xantrex's statement that they can run all handheld power tools. The truth is that they can run some handheld power tools but when has marketing ever been restrained to the truth?

The only way to deal with the situation is to contact the manufacturer of every device you intend to run off of battery power and specifically ask if it's safe to use that device off of a stepped square wave. Sometimes, you actually have to explain to them what the output from a MSW inverter actually is. Generally, it takes some prodding before you're forwarded to the engineering department to get a real answer. Once you know if any of your devices can't be run off an MSW inverter, you then can decide if you should buy a MSW or PSW inverter. Or you can just say the hell with it and buy a PSW to begin with and know you're covered.

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Re: Solar Question(s) Please Help

Post by williaty » Thu Sep 26, 2013 8:35 pm

angelofwar wrote:Interested in those fuse boxes specifically. Got a link?
I have no idea what brand he's using there, but both Blue Sea Systems and Cooper/Bussman make products that look like that and fulfill that function. My preference is for Blue Sea because their catalog is MUCH easier to search through, they provide an immense amount of helpful information about battery-backed power systems for free, and their specs are usually a little better (especially their AICs) than Cooper/Bussman's.

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Re: Solar Question(s) Please Help

Post by Benny » Thu Sep 26, 2013 9:42 pm

williaty wrote: ... both Blue Sea Systems and Cooper/Bussman make products that look like that and fulfill that function. ...
Those look similar (but not exactly like) some of the Blue Sea systems I found when I was building my semi-portable system. That's what I went with too, and I'm pretty happy with them.
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Re: Solar Question(s) Please Help

Post by teotwaki » Fri Sep 27, 2013 1:20 pm

angelofwar wrote:
teotwaki wrote:The set up in my trailer's nose box with the 1500 watt inverter on the left

Awesome teotwawki!!! You build it yourself? Interested in those fuse boxes specifically. Got a link?
Thank you!

Yes I did build it. The fuse boxes are from Blue Sea. I can give a couple of links but you'd want to shop around for best pricing
http://www.starmarinedepot.com/blue-sea ... 7AodJl4A6g" onclick="window.open(this.href);return false;

http://www.starmarinedepot.com/blue-sea ... cover.html" onclick="window.open(this.href);return false;
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Re: Solar Question(s) Please Help

Post by teotwaki » Fri Sep 27, 2013 1:35 pm

Williaty,

one thing that you did not touch on specifically but I would like to know your thoughts about has to do more with off the grid designs that the OP may be interested in. Key things that you mentioned was your selection of 24 VDC battery banks, AC powered LED lights and the other was going for true sinewave inverters. Your points about timing dependencies were very interesting.

My interest would revolve around the fact that no matter what your DC system voltage is, it is more efficient to distribute higher AC voltages over long wires than it is DC voltages. (The old Tesla- Edison rivalries! http://en.wikipedia.org/wiki/War_of_Currents" onclick="window.open(this.href);return false;). But since we cannot store AC voltage we are forced to use batteries as the basis for our systems.

It is also more practical for AC anyhow given that our houses are wired that way, LOL.


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Re: Solar Question(s) Please Help

Post by williaty » Fri Sep 27, 2013 1:54 pm

Going to answer back to front on this one:
My interest would revolve around the fact that no matter what your DC system voltage is, it is more efficient to distribute higher AC voltages over long wires than it is DC voltages. (The old Tesla- Edison rivalries! http://en.wikipedia.org/wiki/War_of_Currents" onclick="window.open(this.href);return false;). But since we cannot store AC voltage we are forced to use batteries as the basis for our systems.
That's not quite entirely accurate. If we could use a 120VDC power system it would be equally efficient over equal distances as a 120VAC system. The reason that's not commonly done is making large conversions to DC voltages is much more complex than making large conversions to AC voltages (where you can use a transformer). Additionally, interrupting a DC circuit in an emergency is much harder than interrupting an AC circuit (since the DC lacks the zero crossing that extinguishes the arc for AC) and it only gets worse as you raise the DC voltage. So, really, it's not that DC power transmission is less efficient, it's that efficient DC power transmission is a pain in the ass. However, on a giant industrial scale, High Voltage Direct Current (HVDC) power transmission lines are not uncommon at all. The biggest advantage is that, lacking phase and frequency, you don't have to synchornize each end of the link. Wiki has a good page about HVDC.
teotwaki wrote:one thing that you did not touch on specifically but I would like to know your thoughts about has to do more with off the grid designs that the OP may be interested in. Key things that you mentioned was your selection of 24 VDC battery banks, AC powered LED lights and the other was going for true sinewave inverters. Your points about timing dependencies were very interesting.
The rule of thumb I was told by several different people who work professionally in the alternative energy industry is that, in a home/boat/RV system, for each kilowatt of system power, it's a good idea to add another 12V. This tops out at 48VDC, because at 50VDC, the code changes completely. The reason this is done is that, for instance, at 1kW on a 12VDC-nominal system, you're moving some pretty damned big currents (~80A) and your wiring has to be crazy large. By doubling up to 24V, you halve the current and can reduce the wire size. Doubling again to 48V by the time you get to 4kW produces similar reductions in wiring requirements. More importantly, for holding the wiring size constant (maybe you can't fit anything bigger than 0 AWG wire through the wall or something), as you increase system voltage you reduce transmission losses (makes the system more efficient). Finally, if you're solar powering the system, it's usually more efficient to put several panels in series to raise the voltage, which reduces the current, which makes the transmission to your solar charge controller more efficient. Having a higher system voltage on the battery side means the input and output voltages of the SCC are closer together, which also increases efficiency.

Even at 48V, if I wanted to move any meaningful power more than about 10' or so, it's probably worth converting to AC via a properly-sized high-efficiency inverter. You'll have ~1/3 the efficiency loss you would from a 48V transmission or about 1/10th the power loss you would with a 12V system. If you're talking about a 90% (from 12V) improvement in transmission efficiency, the ~10% you're losing in the inverter is trivial; it's a big net gain. So the things on the bench/wall with my alternative power system are mostly DC (if I can run them direct from the 24V battery bank) but I send power around the rest of the house at 120VAC because it's more efficient even in a house as small as mine.

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Re: Solar Question(s) Please Help

Post by Sun Yeti » Sat Nov 16, 2013 10:41 am

It so happens I have some pretty strong feeling on the subject of using LED light bulbs on an invertor vs. using 12V LED lights, but I will try not to make this a rant. Here is a comprehensive list of problems with the former arrangement:
-Losses due to inverter efficiency (even with a good inverter, there will be at least a few percent)
-Base power loss in the invertor. The Xantrex invertor that was mentioned earlier in the thread is very good in that it has a low standby power (which, correct if I am wrong, it uses all the time, even when it is powering things), but if all you are running is a few LED lights, that's still a significant ratio of non-useful watts to load watts.
-Losses due to the switching power supply in the lightbulb. There are some decent LED driverse out there (efficiency greater than 80%, power factor greater than 90%), but they cost more than your average LED lightbulb, and they take up more room. To get an LED driver small enough to fit in a lightbulb, you have to make a number of sacrifices. A common one is power factor. The power company charges residental users by watts (not volt-amps) most places, so regular comsumers don't notice or mind, but many LED light bulbs have a power factor as low as 0.6. If you are generating your own power, this is a concern (although it won't actually cost you 40% more power in that example; see this thread on candlepowerforums for more info: http://www.candlepowerforums.com/vb/sho ... wer-Factor" onclick="window.open(this.href);return false;). And on top of that, the lightbulb power supply is unlikely to be much more that 85% efficient.
-The switching power supply in the lightbulb can generate radio noise and interfere with radio communications (another corner they cut to make the power supplies small).
-Lower lifespan/less reliablility. I've had a few '20 year' LED lightbulbs that died in one or two years. The LEDs were probably still good, but the power supply is a piece of sophisticated electronics, with a load of failure-prone components.
-Heat problems: LEDs are happier the colder they are. Imprisioning them in a sealed glass hemisphere with their own waste heat and a bunch of other heat-generating electronics reduces their operating efficiency and lifespan. This is why LED lightbulbs look so crazy with all the fins and so on, trying desperately to dump heat.

My small business manufactures LED light fixtures that electrically consist of top quality LEDs, and a appropriately sized ballast resistors (http://www.yetisolar.com/products/exclamation-light" onclick="window.open(this.href);return false;). They are well-heatsinked using thick aluminum and vertical air convection. We follow the KISS (Keep It Simple, Stupid) principle. The LEDs could take 3 to 4 times the current they run under normal conditions, so even if the charge controller goes nuts and trys to put 16 volts into the battery (and connected lights), they would still be fine (although noticably brighter). Yes, if the battery is really low the lights will get slightly dimmer, but I consider that a feature, not a bug (it lets you know your battery is getting low). It's true what williaty said that more R&D dollars go into 120V AC problems, but those problems are also much bigger. If there was more R&D dollars going into coal-fired airplanes, that still wouldn't necessarily mean they were better! And yes, there is a lot of cheap, 12V crap out there, but good DC LED lighting will always beat good AC LED lighting until they can make inverters and LED drivers that are 100% efficient with a power factor of 1.0 and no standby power that are as reliable as LEDs (the LEDs themselves can last 20 years or more), and cost almost nothing. In other words, not for a very long time. I really think that as renewable energy gets more widespread, DC lighting will also become more prevalent.
I find it uniquely frustrating that so many preppers have their heads in the sand about climate change.

But, I've come to realize there's no point in arguing with someone if there's no possible evidence you could present that would actually change their mind.

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Re: Solar Question(s) Please Help

Post by williaty » Sat Nov 16, 2013 1:44 pm

Sun Yeti wrote:-Losses due to inverter efficiency (even with a good inverter, there will be at least a few percent)
VS the losses in the wires because 12V requires moving 10x the current. Parasitic losses in the wire rise by the square of current, so you're burning off 100x more power as heat in the wire using 12V LEDs than you are using 120V LEDs.
-Base power loss in the invertor. The Xantrex invertor that was mentioned earlier in the thread is very good in that it has a low standby power (which, correct if I am wrong, it uses all the time, even when it is powering things), but if all you are running is a few LED lights, that's still a significant ratio of non-useful watts to load watts.
As I believe has been noted in this thread, choosing a high efficiency (above 90%) inverter with a small base load (meaning sized properly to the load it'll be powering) is important.
Losses due to the switching power supply in the lightbulb. There are some decent LED driverse out there (efficiency greater than 80%, power factor greater than 90%), but they cost more than your average LED lightbulb, and they take up more room. To get an LED driver small enough to fit in a lightbulb, you have to make a number of sacrifices. A common one is power factor. The power company charges residental users by watts (not volt-amps) most places, so regular comsumers don't notice or mind, but many LED light bulbs have a power factor as low as 0.6. If you are generating your own power, this is a concern (although it won't actually cost you 40% more power in that example; see this thread on candlepowerforums for more info: http://www.candlepowerforums.com/vb/sho ... wer-Factor" onclick="window.open(this.href);return false;). And on top of that, the lightbulb power supply is unlikely to be much more that 85% efficient.
Short answer to this: shop smartly. All the 120V LED light bulbs I have have an electrical efficiency above 90% and a power factor above 0.9. Sure, I had to pay for it. But if you want to cheap out and pay $5 for a A19 replacement, you're going to get crap and you deserve it.
-The switching power supply in the lightbulb can generate radio noise and interfere with radio communications (another corner they cut to make the power supplies small).
I'm a ham radio operator. I have zero problems from my 120V LEDs producing RFI. Again, I buy good LEDs only. I do have problems with CFLs and linear florescents producing RFI though.
-Lower lifespan/less reliablility. I've had a few '20 year' LED lightbulbs that died in one or two years. The LEDs were probably still good, but the power supply is a piece of sophisticated electronics, with a load of failure-prone components.
Again, buy quality. The Philips L-prize winning lamps have over 18-years equivalent run time in government testing labs and they're still going. If you cheap out, you deserve what you get.
-Heat problems: LEDs are happier the colder they are. Imprisioning them in a sealed glass hemisphere with their own waste heat and a bunch of other heat-generating electronics reduces their operating efficiency and lifespan. This is why LED lightbulbs look so crazy with all the fins and so on, trying desperately to dump heat.
This is a red herrring. Your 12V LEDs have exactly the same problems with heat. Die temperature is a function of current run through the emitter and the efficiency of your thermal path to the outside world. So those fins you mock are a sign of a job well done. If you're not doing that, you're either risking burning up the emitter or you're running a small fraction of the potential output of the LED.
My small business manufactures LED light fixtures that electrically consist of top quality LEDs,
It's nice to have you admit your post was spam.
The LEDs could take 3 to 4 times the current they run under normal conditions, so even if the charge controller goes nuts and trys to put 16 volts into the battery (and connected lights), they would still be fine (although noticably brighter). Yes, if the battery is really low the lights will get slightly dimmer, but I consider that a feature, not a bug (it lets you know your battery is getting low).
So your output varies with voltage input. Knowing the curve for LEDs, your output varies a LOT with input unless you're doing something to stabililze it. To a lot of us, that's not a feature, that's a show-stopper failure of the product. When I flip the switch, I want a predictable amount of light. So, now I have to use a voltage regulator with your product, which has roughly the same efficiency losses as inverting to 120V. If I want to know my batteries are dying, I'll look at my battery monitor, which is required tech anyway.
but good DC LED lighting will always beat good AC LED lighting until they can make inverters and LED drivers that are 100% efficient with a power factor of 1.0 and no standby power that are as reliable as LEDs (the LEDs themselves can last 20 years or more), and cost almost nothing.
The problem is that there's (as far as I've ever been able to find) no good consumer-ready DC LED lamps out there. I'm not interested until it's greater than 90 lm/Watt, CCTs of 2700K and 4100K available, and a CRI greater than 90 off the shelf that I can just walk in and pick up. That doesn't exist yet in a marketable form that I've ever seen an ad for. Sure, I could pick up a Nichia 219, but then what? I have to have the skills to solder and fabricate something usable out of it. Even once all those requirements are met, you still have the problem of how incredibly inefficient 12V power distribution is. Running 12V the length of the house is going to require either HUGE wires or be HUGELY inefficient.

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Re: Solar Question(s) Please Help

Post by Sun Yeti » Sat Nov 16, 2013 11:03 pm

Yes, obviously my long, detailed post was spam written by a robot :) And this reply must also be spam written by a robot. In fact, probably everyone else on the internet is a robot and you are the only real person. It must be lonely...

OK, flaming aside, let me reply. You happened to claim that something doesn't exist that I make for a living. I mentioned what I do because it was relevant to the conversation. LEDs draw a very small amount of current, so wire losses are not a big deal. For example, with the lights I referenced, I can run 30 feet of 16 gauge wire for less than 1% losses. If necessary, I can reduce the size of the ballast resistor and do even longer wire runs (wire resistance replaces some fraction of ballast resistance) without effecting brightness or efficiency. It is definitely important to size your inverter properly, I don't disagree.

There is a variety of quality in LED bulbs and you get what you pay for. LED bulbs are useful if all you have is AC power light fixtures that you want to retrofit. But, even with the fins they can't complete in terms of heat dissipation with a fixture that can cool by free air convection and conduction through a vertical aluminum plate. AC fixtures will likely move beyond the bulb soon as well. Proof is in the pudding (see efficiency paragraph below).

Because the resistance of LEDs increases as applied voltage declines, the change in amount of light is not discernible until the battery is almost dead. If completely constant light output is top priority for you, I guess that's your call, but our eyes percieve light on a log scale, so a 10 or 15% change is not even going to register for most people.

My LED light fixtures has slightly variable efficiacy with applied voltage, but a minimum of 120 lumens per watt (even Cree's LED bulbs, which are some of the best, only get 88 lumens/watt at 5,000 K). The color temperature on my fixtures is about 5,000 K, which is a bit higher than you are looking for. The CRI is a bit lower than your preference, at about 75. They don't fit all of your color requirements, but they are a lot more efficient than bulbs, and they are very user friendly off the shelf. Not everyone is as picky about color as you are, and CRI will continue to improve as new LEDs come out. And really, do the math, the transmission loss is way less than you think. The world changes fast. Perhaps the last time you checked there weren't any good DC fixtures, and maybe you got burned buying some crappy ones, but that doesn't mean they don't exist now.

So I think it's a bit much to claim that all DC light fixtures are crap. Perhaps I am taking this a bit personally, as this is something I have been working on for years. If someone claimed that what you do for a living is both impossible and wrongheaded, you might react the same way. If you have more real questions/comments about the technology (and there were several interspersed in your last post which I addressed), I would be happy to discuss this further. But I could do without the vitriol.
I find it uniquely frustrating that so many preppers have their heads in the sand about climate change.

But, I've come to realize there's no point in arguing with someone if there's no possible evidence you could present that would actually change their mind.

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Re: Solar Question(s) Please Help

Post by williaty » Sat Nov 16, 2013 11:30 pm

Sun Yeti wrote:OK, flaming aside, let me reply. You happened to claim that something doesn't exist that I make for a living.
PM me and I'll give you an email address to send a spec sheet to. If you really are shipping a viable product with >90lm/W, >90 CRI, and a CCT of 2700K or 4100K, my wife is about to re-do all her under-cabinet kitchen lighting with your product. If they don't meet those specs, or the product really isn't shipping yet, then, well, my point still stands. If you deliver, you'll have a review here and on CPF about your product's success.
The color temperature on my fixtures is about 5,000 K, which is a bit higher than you are looking for. The CRI is a bit lower than your preference, at about 75.
CRI of 75 is TERRIBLE. That is completely unsuitable for any type of in-home lighting. Mid-80s is minimum acceptable to most people and I'm picky enough to require >90. The funny thing is that I designed lighting professionally for a few years. I've had to deal with turning what the engineers want to offer into something the customer will actually be willing to put up with without complaint. 75 CRI causes complaints.

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Re: Solar Question(s) Please Help

Post by teotwaki » Mon Nov 18, 2013 1:14 pm

Sun Yeti wrote:Yes, obviously my long, detailed post was spam written by a robot :) And this reply must also be spam written by a robot. In fact, probably everyone else on the internet is a robot and you are the only real person. It must be lonely...-------------------SNIP--------------. But I could do without the vitriol.
Nobody expects the Spanish Inquisition! LOL
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Hang in there Sun Yeti! Some here may have "loud" voices but they are just broadcasting their own opinions. :mrgreen:
My adventures and pictures are on my blog http://suntothenorth.blogspot.com

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Sun Yeti
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Joined: Mon Oct 21, 2013 4:54 pm
Favorite Zombie Movies: 28 Days Later, Zomblies (no, that's not a typo)

Re: Solar Question(s) Please Help

Post by Sun Yeti » Mon Nov 18, 2013 6:47 pm

Yeah, I really shouldn't have taken it so personally. I haven't posted that much before, and I imagine I will get a thicker skin to that sort of thing with time. Nothing clarifies ones ideas on a topic better than having to defend them in an intelligent debate. We PM'd a bit, and basically, I will let him know if/when I start making lights with a bit higher CRI (color rendering index). It was nice that we were able to go forward with a civil conversation about this even though we have some differences in taste/priorities for lighting. And, it was probably better to take that to PM, so as to avoid hijacking the thread.

Some people (like myself) don't really notice color/CRI of everyday lighting, thus whatever is the most efficient is the way to go. However, for some other people (like williaty), CRI is one of their primary concerns. Because I proritize efficiency in my lights, the CRI is still a bit low for some people. Likely that will change with time, as even the high-efficiency LEDs get a few points better on CRI with every generation.

Anyway, thanks for the spanish inquisition pic. I'll hang in OK. Not leaving any time soon.
I find it uniquely frustrating that so many preppers have their heads in the sand about climate change.

But, I've come to realize there's no point in arguing with someone if there's no possible evidence you could present that would actually change their mind.

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