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Light string has contradictory instructions

Karen Field
8/27/2010 11:45 AM EDT

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ReneCardenas
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re: Light string has contradictory instructions
ReneCardenas   9/8/2010 4:36:10 PM
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To wswbln: I agree, we have allowed our society to seek legal recourse at every instance of self inflicted injury and demonstration of absent common-sense. I don’t have the solution, but would like to see the courts bring a deterrent for frivolous lawsuits, maybe by requiring payment of all court costs including defense attorneys fees in all failed cases, so may be the bar can be raised just a little to stop stupidity in courts.

David Ashton
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re: Light string has contradictory instructions
David Ashton   9/8/2010 3:29:54 AM
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Jon...sorry, it's maybe not too obvious from my post, but my tongue was very firmly in my cheek when I wrote the above. I am as in awe of the guys who got men on the moon as anyone else. I was about 14 when we went Metric in Rhodesia where I was as a kid. I remember getting incensed that we were then paying 1 cent, equal to 1.2 of the old pennies, for the same sweets that used to cost us 1 penny. IE, we were getting ripped off 20 percent overnight! I am pretty used to Metric units now, but still revert to imperial occasionally. 6 inches of rain sounds more impressive than 150 millimetres. Working in factors of 10 for everything is easier in some respects (and the fact that US currency is 100 cents to the dollar means that some Americans think so too??) My wife still works obstinately in imperial units and it drives me scatty when she asks me to buy her 45 inches of elastic and they sell it by the metre. I've got pretty good at mental conversions though. And I'm very conscious of the fact that DIL ICs have pins spaced 0.1 inches apart at a width of 0.3 or 0.6 inches. So when I see a connector with 2.54 mm spacing I wonder, for a few seconds, what they are on about....My PCB design program still works in inches and I wouldn't want to change that. So no offence meant. It would be nice if the whole world used one system, whatever it was, but I don't think this will happen anytime soon....

wswbln
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re: Light string has contradictory instructions
wswbln   9/6/2010 10:36:25 AM
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@jonhp: Please don't take it personal, but I'm too very amused when I look in an american physics textbook and see all this (in my eyes) cumbersome correction factors. When Germany changed to the SI system in the early 70es I too had some problems first to see the drive behind the "metrication" (as you put it), but later learned to love the ability to derive the correct formulas my simply looking at the units. Knowing that 1kg*m/s² is 1N unlocks half of Newtonian mechanics and dynamics and passing my tests on thermodynanics so easily was also owed to this. I somewhat admire (or more so commiserate) US pupils for memorating all the scale factors that can't really make life easier, I think. But it really makes me shake my head when programmers of PCB layout programs base their internal computing on mils and have to deal with many positions after decimal point and rounding errors when the other way round would solve this in an elegant way. and @ReneCardenas: Isn't it funny to appeal for the use of common sense to people that force the placing of "Caution - slippery when wet" signs when cleaning the floor in order to avoid suing? NAd if there is a plug for daisychaining other loads, someone WILL plug 5 other strings or the electrical heater in there. After the house burnt down, he will then sue the dealer, the power company and whom else...

jonhp
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re: Light string has contradictory instructions
jonhp   9/5/2010 9:21:31 PM
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The shear arrogance of the "metrication" nuts is really getting to me lately. The USA space program is a success due to the skill, ability and hard work of thousands of scientists, mathematicians and engineers and has little to due with the measurement system used to define millions of parts, lines of code or what have you. You do all these fine people a grand injustice. Maybe some view English metrics as arbitrary, but what makes the meter less arbitrary: 1889-1960: one ten-millionth the meridian distance from the equator to the pole; 1960-1983: 1,650,763.73 wavelengths of orange-red radiation of krypton 86 1983-: 1/299,792,458 of the distance light travels in a vacuum in one second. Quarts work as good as liters, inches as well as centimeters, miles as well as meters etc. And making things metric, doesn’t necessarily make them more human friendly or easier to use. ¾” plywood in the USA is now 19mm thick. One third of the old version is ¼”. 1/3 of the “metric” version is 6.3333… Very hard to find on a metric ruler! And English metric doesn’t mean just fractions either. We measure rain in 0.01” increments. The metric equivalent is 0.2mm; it’s decimal but not easier. Type is measured in 0.1” increments. And on and on. I think if people, business, government, educators find value in the metric system; then fine use it. But forcing change in the measurement system doesn’t always help in the real world and it shouldn’t be a “cause” into and of itself.

David Ashton
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re: Light string has contradictory instructions
David Ashton   9/5/2010 12:54:11 AM
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Maybe I'm like these guys who say Vinyl has a warmer sound than CDs, but incandescent bulbs do have a nice warmth about them that LEDs (even the warm white ones) don't begin to match. I have a set of basket-weave type round lampshades that I bought on a trip to Madagascar years ago. Clear incandescent bulbs look great in them and cast nice patterns on the wall and ceiling, primarily because they are an almost point source, omnidirectional source. Can a LED match that? (Even frosted incandescents look terrible in them.) Incidentally, standard size incandescent bulbs are almost unobtainable in Australia now but I did manage to get some high-efficiency halogen types which are an even better point source. Horses for courses I guess, I have CFLs most other places in my house.

WKetel
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re: Light string has contradictory instructions
WKetel   9/3/2010 9:28:36 PM
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One more thing, which is that in the state of California it is advised to not eat these strings of lights, based on the allegation that they contain lead. Possibly on the base of the lamp, so don't eat the lamps either. ONLY from our guardians in California do we get such vital advice.

WKetel
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re: Light string has contradictory instructions
WKetel   9/3/2010 9:25:59 PM
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It is clear that I did not examine the picture closely enough the first time I commented. I was thinking about the strings of 50 lamps, and the whole string may be 5, 10, or 15 watts. These are much bigger bulbs, and so the connecting wire may be as big as #18, although my guess would be #20. USA wire sizes relate inversely to the current handling capacity, a very logical arrangement, Asho #1. So it would be fine for 1 string and OK for 2, and 3 is undoubtedly the limit. The very first part to fail will be the contacts at the fuses internal to the power plug. Typically these are made with the cheapest possible injection molding process, using the cheapest possible polyethylene plastic available, and the contacts are some sort of brass alloy that develops an insulating oxide layer after a few weeks.

ReneCardenas
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re: Light string has contradictory instructions
ReneCardenas   9/2/2010 10:11:41 PM
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But even those LED strings have to deal with that pesky power issue, that is, if you want to be safe and not burn the house! In a serious note, those strings still have limits on how long can they be, and how many you are able to connect in series.

ReneCardenas
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re: Light string has contradictory instructions
ReneCardenas   8/30/2010 4:25:35 PM
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Just realize that there is a 2000 character postings. And the paragraphs are not been formatted as typed in word file. The link below and additional notes relate to the posting above. http://www.powerstream.com/Wire_Size.htm 5 Watt lamp (x20) string http://images.restorationhardware.com/content/catalog/product/pdfs/prod1673011_info.pdf 7Watt lamp (x10) string http://images.restorationhardware.com/content/catalog/product/pdfs/prod1673011_AI.pdf PARTY GLOBE LIGHT STRING $35 - $39$31.49 - $34.99 Miniature versions of lights seen in Italy's piazzas and the Tuscan countryside. • Illuminate outdoor gatherings • All-weather wiring • UL-listed for indoor or outdoor use • Large globes (70W) come 10 lights to a string • Small globes (100W) come 20 lights to a string • Three light strings can be connected end to end • Large globes: 11'L; bulb size, 2-1/4"D • Small globes: 21'L; bulb size, 1-1/2"D • PROPOSITION 65 WARNING: This product contains lead, a chemical known to the State of California to cause cancer and birth defects or other reproductive harm • This item cannot be shipped to Canada

ReneCardenas
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re: Light string has contradictory instructions
ReneCardenas   8/30/2010 4:23:13 PM
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Gentlemen, if anyone would have taken a quick tour to the actual link, there is more data that is missing in this posting. For starters, the problem has two variables, this product is sold as a string of 10 or 20 lamp strings. In other words, 7Watt-lamp sting dissipated 70Watt total & 5Watt-lamp string dissipates 100 Watts total. (Or about 0.6Amps and 0.83 Amps respectively). The photo is clearly for the 100Watt string version, so far so good, thinks make sense. Also if you read the additional information posted below, it can be seen that the manufacture provides a 5 Ampere fuse. So for a typical derating of 80% of the maximum load current. If the fuse was the only weak link, there is enough safety margin to install 3 strings (from this vendor) in any combination using the same type and power limited to 100 Watts per string. However, given that there is another variable not clearly stated in the posting or by the vendor or manufacturer, “the gauge of the electrical cable” in this case. Cable gauge is a critical safety parameter that defines the capacity to deliver power safely power down stream, to other loads or lighting strings. Using the guesstimate by WKetel, and using the conservative 700 circular mils/Ampere rule-of-thumb the cable (AWG#26 is rated to 0.36A) would be barely safe to be connected individually since a single lowest-power string (70W) needs a rating of at least 0.6 Amps. If the manufacturer (very unlikely), had used AWG#16 or #19, then there would be reason to feel with confidence that the 3 string configuration was safe. However, that would be a very stiff and heavy cable. In other words, use your common sense and feel the temperature of the cable at the start of the string to see if the wiring is under rated. It should feel not higher than couple of degrees over room temperature. So like many thing in engineering, apply common sense, and do not exceed the cable rating by applying a space heater at the lighting string end!

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