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From Wikipedia

Symbol

A symbol is something such as an object, picture, written word, sound, or particular mark that represents something else by association, resemblance, or convention. For example, a red octagon may be a symbol for "STOP". On maps, crossed sabres may indicate a battlefield. Numerals are symbols for numbers (amounts). All language consists of symbols. Personal names are symbols representing individuals.

Psychoanalysis and archetypes

Swiss psychoanalyst Carl Jung, who studied archetypes, proposed an alternative definition of symbol, distinguishing it from the term sign. In Jung's view, a sign stands for something known, as a word stands for its referent. He contrasted this with symbol, which he used to stand for something that is unknown and that cannot be made clear or precise. An example of a symbol in this sense isChrist as a symbol of the archetype called self. For example, written languages are composed of a variety of different symbols that create words. Through these written words, humans communicate with each other.Kenneth Burke described Homo sapiensas a "symbol-using, symbol making, and symbol misusing animal" to indicate that a person creates symbols in her or his life as well as misuses them. One example he uses to indicate his meaning behind symbol misuse is the story of a man who, when told a particular food item was whale blubber, could barely keep from throwing it up. Later, his friend discovered it was actually just a dumpling. But the man's reaction was a direct consequence of the symbol of "blubber" representing something inedible in his mind. In addition, the symbol of "blubber" for the man was created by him through various kinds of learning. Burke emphasizes that humans gain this type of learning that helps us create symbols by seeing various print sources, our life experiences, and symbols about the past.

Burke also goes on to describe symbols as also being derived from Sigmund Freud's work on condensation and displacement further stating that they are not just relevant to the theory of dreams, but also to "normal symbol systems". He says they are related through "substitution" where one word, phrase, or symbol is substituted for another in order to change the meaning. In other words, if a person does not understand a certain word or phrase, another person may substitute a synonym or symbol in order to get the meaning of the original word or phrase across. However, when faced with that new way of interpreting a specific symbol, a person may change their already formed ideas to incorporate the new information based on how the symbol is expressed to the person.

Etymology

The word symbol came to the English language by way of Middle English, from Old French, from Latin, from the Greekσ�μβολον (sýmbolon) from the root words συν- (syn-), meaning "together," and βολή (bolē), "a throw", having the approximate meaning of "to throw together", literally a "co-incidence", also "sign, ticket, or contract". The earliest attestation of the term is in the Homeric Hymn to Hermes where Hermes on seeing the tortoise exclaims σ�μβολον ἤδη μοι μέγ᾽ ὀνήσιμον "symbolon [symbol/sign/portent/encounter/chance find?] of joy to me!" before turning it into a lyre.

Role of context in symbolism

A symbol's meaning may be modified by various factors including popular usage, history, and contextual intent.

Historical meaning

This history of a symbol is one of many factors in determining a particular symbol's apparent meaning. Old symbols become reinterpreted, due perhaps to environmental changes. Consequently, symbols with emotive power carry problems analogous to false etymologies.

For example, the Rebel Flag of the American South predates the American Civil War. An early variant of the crossed bars resembled the Scottish Flag.

Juxtaposition

Juxtaposition further complicates the matter. Similar five–pointed stars might signify a law enforcement officer or a member of the armed services, depending the uniform.



From Yahoo Answers

Question:

Answers:The triangle is a 'Delta' style winding. Each line of the triangle represents a transformer winding between 2 phases of the 3-phase power lines. There is no 'ground' connection. .

Question:Question... If I have 5 single phase 120VAC, 20Amp circuits coming to a piece of equipment for power and I want to change that to bringing in 3 phase nuetral and ground to a power box and distributing the power in the power box and make my single phase circuits from there (putting the 20 circuit breakers in there for the 20 amp circuits). What 3 phase power requirement do I have is it simply 100 amps three phase or do I have to figure in the 1.73 (square root of three factor) x the 100Amps. Thanks ahead The wiring is not or does not exist I am just looking at how to do it. I think bringing 3-phase 5 wire (3-phases, neutral, ground) 208VAC at whatever amperage is a better way to do it. Instead of 5 separate 120VAC/20Amp circuits and 5 breakers in the main breaker panel. So if I have 100 amps of single phase load. 100A x 120V = 12000W so 12000W / 208V = 58A 58A / 1.73 = 33.5A per phase? What you do is add up the total Wattage or KVA with the voltage you know/have. divide by 1.73, divide by the new 3 phase voltage and voila you have the new 3 phase current... so 12000W (120V x 20A) / 1.732 = 6928.4 / 208V (3 ph V) = 33.3 Amps @208V, 3 phase current.

Answers:Ken, power is power, so 5 times 20 A single phase 120v is 12kW. 3 phase power will be 230V, so you will need 35A (33A actually, but I'm rounding.) per phase to equal the same power. You may however have problems distributing the power per phase and you can't combine two of the phases if you don't have enough current available on a given phase for a given circuit, so you might have to bump the service up to 40A or more in order to distribute the power without having a circuit that needs more power than any of the three phases can supply by itself.

Question:Answers to my previous question implied that I should use 3-phase power in the (large) house. I know that you can power 120V outlets on one of the 3 phases connected to neutral/ground. That'll work for most of the house. However, what do I do about 240V appliances? Joining 2 phases only gives 208 volts. That's not going to power an electric range and water heater properly, is it?

Answers:Regarding resistance-heating devices such as an electric water heater or a range, the power they produce drops to approximately 75%, found by squaring the voltage ratio: (208V/240V)^2 = 0.751 = 75.1% In the case of the water heater, it will run 33% longer to make up the difference. So will the range top, unless the elements are thermostatically controlled, in which case they will duty-cycle on longer so that the heat output is the same (up to 75.1% maximum). The other thing to consider is whether you have any motors that you want to run. On a 240V system, a motor nameplate rating of 230V is proper (or 460/230V, or 460/230-208V). On a 208V system, the proper motor nameplate rating is 200V, not 208V. A triple-rated motor (460/230-208) will run on 208V, but not down to a 90% voltage rating at full torque, horsepower and efficiency as required by NEMA. Or in other words, you can do it, but if the utility's voltage sags (to the extent it is allowed), your motor will run less well than expected. So, if you have any say in the motors that you purchase, select ones rated at 200V. To revisit your previous question, you stated that you needed a 400A single-phase panel because 200A isn't large enough. The local utility around here considers that to be a class 320 panel (320 amps continuous, 400 amps maximum), as you can only load a breaker to 80% maximum with continuous loads, with continuous loads being defined as ones that last 3 hours or longer. The local utility has no problem supplying power to that size of panel. If your load is over 400A, they can require you (at their option) to go with 3-phase power (e.g., 208V 200A) which some people don't want because they'd rather have 240V for the reasons discussed above. So if you want 120/240V single phase, ask your utility, I'm sure you can have it. You asked whether to have one 400A panel or two 200A panels. The utility will provide power only to one device (called the service entrance equipment). At minimum it is a meter base (the socket) with either a disconnect switch or a main circuit breaker. You can buy a combination "meter-main" which is the meter socket and a main breaker, or you can buy a combination meter-main-panelboard that includes branch breakers. Where I am going with this is that you can't have the utility connect to two 200A panels, but you could have a main breaker with two 200A feeder breakers that serve feeders to two 200A panels that are located wherever you desire. One other point. Are you familiar with doing load calculations per the National Electrical Code? If not, consider having an electrician or engineer or someone experienced run through the calculations for your house. There are various ways of computing the total load, and it may well be less than 200A if done per procedure.

Question:Hi guys, In a data centre, a rack current reading shows 60 amp. Voltage is 235 V How is the calculation done? Calculation 1 - current x voltage x 3 phase = watts / 1000 = kva x power factor = kw 60 x 235 x 1.732 = 24421 watts / 1000 = 24.42 kva x 0.8 = 19.53 kw And Calculation 2 - VLN x 1.732 = VPP 235 x 1.732 = 407 Given 28 amp per phase (stated in server manual) current x voltage x 3 phase / 1000 = kw 28 x 407 x 1.732 / 1000 = 19.73 kw Calculation 1 is what i learnt but supplier is proposing calculation 2. Which of the above calculation is correct ? And for calculation 2, (VLN x 1.732 = VPP) 3 phase power already multiplied but why multiply by 1.732 again? Thanks in advance guys!

Answers:You may notice that there is a discrepancy between your measured 60A and the 28A in the manual. It would help to know a little more about the load, are there three separate single phase loads delta connected to a three phase service? Calculation 2 is weird. If it is a calculation for a single phase load, the 1.732 factor is not needed, but. if there are three single phase loads delta connected to the three phase supply, then since 1.732 x 1.732 = 3; 28 x 235 = 6.58kVA per load 6.58 x 3 = 19.74kVA total once one delta connects the three loads the supply current will be 28 x 1.732 = 48.5A per phase since two loads are on each supply conductor, while that is less than your measured 60A it is closer than the 28A from the manual 48.5A x 235V x 1.725 = 19.74kVA

From Youtube

3 Phase Power :This is a diagram of how 3 Phase Power works

Phase 3 - PART 2 *Religious Symbols* ORIGINAL :All 20 Parts Excluding The Three Trailers.. -- I, Achernahr, hereby give my approval and support for RezaKhalilZada to upload The Arrivals and all other WUP material onto his account for the purpose of spreading the information many have found to be crucial and relevant. -- All these uploads are purely for educational purpose, not for advertising or using the Audio claiming it's my own. Therefore I'm not breaking any law.