what does R, S, T labelled wired stand for in 3 phase wiring? Thanks.?
411855
R, S and T as consecutive letters are used to name the 3 different phases. I am not sure why they those 3 have been chosen.
701526
I found a rather technical but useful page about this.\n\nIt seems without fully reading the page that RS485 uses balanced lines, which means it has two wires for the signal rather than one, the second wire carries an inverted version of the data.\n\nThe reason behind this is that if the cable picks up current from neighbouring cables it will be the same on both wires and will be distinguished from the data because the data always shows up as an opposite signal on the second wire.\n\nThis makes for quite a robust line (in terms of magnetic, electrical and radio interference) which allows you to use the serial link over much longer distances.\n\nThere are other differences but I’ll let you read about them.
549392
In electronic components, the designations for the component usually has two letters, followed by a serial number of a manufacturer.  The first letter stands for the material. In this case, the first letter, "B", stands for silicon.  The second letter, "C", indicates the type of component, which is indeed a transistor.\n\nEXTRA INFO: In some cases, the number may contain a suffix, which indicates the grade, or reliability factor, of the component.
265030
I couldn't tell you why a transmission Line has a ground wire attached, unless somebody thought it was a good place to put one. lol umm, details..?
947411
Depending on the utility company, some use Dyn11 and others Dyn1 or some other vector group that is universal to their\nsystem.\n\nThe reason being is that  they can be interconnected with the low voltage side of another transformer that is connected to the same high voltage supply circuit.\nDyn 11 means that the vector group is at the 11 o'clock position. If for instance two transformers on the same high voltage line side had different vector groups say Dyn11 and Dyn 1 they would always be 30° out of phase, this would mean that should they be interconnected they would immediately trip the incoming CB/fuses.\n\nSource: Electrical Engineer (ret.) with 45yrs experience
998724
ANSI/EIA (American National Standards Institute/Electronic Industries Association) Standard 568 is one of several standards that specify "categories" (the singular is commonly referred to as "CAT") of twisted pair cabling systems (wires, junctions, and connectors) in terms of the data rates that they can sustain. The specifications describe the cable material as well as the types of connectors and junction blocks to be used in order to conform to a category. \nThese categories are: \n\n\nCategory  Maximum data rate  Usual application \nCat 1        Less than 1 Mbps    Analog voice (plain old telephone   service) ISDN Basic Rate Interface Doorbell wiring. \nCat 2         4 Mbps                    Mainly used in the IBM Cabling System for Token Ring networks .\nCat 3        16 Mbps                     Voice and data on 10BASE-T Ethernet \nCat 4         20 Mbps                    Used in 16Mbps Token Ring Otherwise not used much \nCat 5         100 Mbps                 100 Mbps TPDDI \n                                                 155 Mbps ATM \n\n\nCAT 5 is currently under consideration to be incorporated into the Gigabit Ethernet specification for short distance wiring. While longer connections using Gigabit Ethernet use optical fiber, the goal is to leverage the CAT 5 twisted-pair wiring most organizations already have in place for connections out to the desktop. \n\nThe two most popular specifications are CAT 3 and CAT 5. While the two cables may look identical, CAT 3 is tested to a lower set of specifications and can cause transmission errors if pushed to faster speeds. CAT 3 cabling is NEXT-certified for only a 16 MHz signal, while CAT 5 cable must pass a 100 MHz test.
303344
http://www.lammertbies.nl/comm/cable/yost-serial-rj45.html\nthis page is very good at explaining it
120987
There are three wires: yellow, red and green.  Same thickness.
979486
In AC three-pin plug a cable having three wires is connected. The green one is earth or ground, the red one is live or Phase and the third one is called neutral.\n\nEarth is connected to the body of your gadget and the other two are connected to the main circuit. When you switch on the gadget the circuit is completed and the device starts running.
936402
International Standard IEC 60898-1 and European Standard EN 60898-1 define the rated current In of a circuit breaker for household applications as the current that the breaker is designed to carry continuously (at an ambient air temperature of 30 °C). The commonly-available preferred values for the rated current are 6 A, 10 A, 13 A, 16 A, 20 A, 25 A, 32 A, 40 A, 50 A, 63 A, 80 A and 100 A (Renard series, slightly modified to include current limit of British BS 1363 sockets). The circuit breaker is labeled with the rated current in ampere, but without the unit symbol "A". Instead, the ampere figure is preceded by a letter "B", "C" or "D" that indicates the instantaneous tripping current, that is the minimum value of current that causes the circuit-breaker to trip without intentional time delay (i.e., in less than 100 ms):\n\nType Instantaneous tripping current\nB above 3In up to and including 5In\nC above 5In up to and including 10In\nD above 10In up to and including 20In
360978
You mean the IEEE regulation?\nThe Institution of Engineering and Technology prepares regulations for the safety of electrical installations for buildings, the IEE Wiring Regulations (BS 7671) now having become the standard for the UK and many other countries.\n\nhttp://www.iee.org/Publish/WireRegs/about-bs7671.cfm\n\nAlso refer to http://www.tlc-direct.co.uk/Book/1.2.1.htm
430412
The wires are placed on the poles according to their voltage - highest voltage on top (farthest away from people) and lowest on the bottom. This means the bottom one(s) is usually telephone (12 volts), then cable tv (30 volts) then the "secondaries" which are what your house runs on (220 volts) and then all the way up top, the "primaries" which carry electricity over long distances, and are usually 13,600 volts.
572836
Three phase power is delivered perhaps to a machine shop with large electric motors.  The motors and transformers (if needed) are often connected in "Y" or "Delta" configurations using all three phases.  The machine shop may also use single phase (for light bulbs?) and two phase (for heaters?).  A single phase to ground provides 110 volts.  Two phase connected together provide 220 volts.  When all three phases are connected 440 volts is provided.  You can often see all three phases up on most power poles and only two phases are connected to most homes (for 110 and 220 volt service).\n\nConsider the analogy between the flow of electric current and the flow of water.  Voltage is like water pressure and current (amps) is like flow rate (gpm).  The three phases represent three different "pipes" between the generator plant and the customer.  Each phase is like a piston pump at the generator that shoves a pulse of water (amps) to the customer then sucks it back (alternating current).  The three phases are connected to the same shaft (like pistons in a three cylinder car) but are evenly spaced (360 degrees/3 = 120 degrees out of phase).  The electrons shoved into the pipe at the generator need not reach the customer before being sucked back.  A like quantity of electrons are pushed into the ground at the customer's installation (communicated at the speed of light!) then pulled back out of the "ground" for reuse.\n\nObviously the power that can be transmitted to the customer depends on whether he/she is using single, two or three phases where P = EI (Power = Voltage x Current).  Hope that helps a little.
512437
Ground or earth in a mains (AC power) electrical wiring system is a conductor that exists primarily to help protect against faults and which in normal operation does not carry current.\n\nThe term "ground" is used in Canada and the U.S.; the term "earth" is used in most of the rest of the English-speaking world. They are used synonymously here.\n\nNeutral is a circuit conductor that carries current in normal operation, and which is connected to earth.\n\n    * In a polyphase or three-wire AC system, the neutral conductor is intended to have similar voltages to each of the other circuit conductors, and similar phase spacing. By this definition, a circuit must have at least three wires for one to serve as a neutral.\n    * In the electrical trade, the conductor of a 2-wire circuit that is connected to the supply neutral point is also referred to as the "neutral". This is formally described in the US and Canadian electrical codes as the "identified" circuit conductor. If the entire system is only single phase then the current carrying conductor that is tied to earth is still a neutral by this definition.\n\nThe NEC and Canadian electrical code only define neutral as the first of these. In North American use, the second definition is used in less formal language but not in official specifications. In the UK the IEE definition is a conductor connected to the supply system neutral point, which includes both these uses.
1063180
first...identify the power source (AC or DC)\nthen...isolate the power source (lockout)\nnext...verify the circuit is not live (test)\n\nfinally...if it is AC three phase reverse any two of the three motor leads, if it is DC just reverse the two leads (if shouldn't be DC)\n\nif it is a european piece of equipment the wires should be black-black-brown, swap the blacks\n\notherwise, it should be brown-orange-yellow or black-red-white\n\nDO NOT ATTEMPT IF YOU ARE NOT QUALIFIED\n\ngood luck
1082346
The "60 each" part of your question says you don't understand the most basic aspects of electricity.  Voltage is a measurement between two points.  Think of a 12V car battery.  It is 12 volts between the 2 terminals of the battery.  Another analogy:  two things that are 3 feet apart are 3 feet apart, not 1.5 feet each.\n\nDoubling 120 is 240, not 220, but I 220 is a commonly used number, like 110 for 120, but the standard voltages are 120 and 240.\n\nI think the point about doubling when you lose a neutral is talking about what is called a multiwire circuit.  The service into your house is the same, and some appliances like your dryer, have the same thing.  For a single phase case, a multiwire circuit has 2 phase (or hot) conductors and a neutral, with 120 volts between each phase and the neutral and 240 volts between the two phases.  This is created by a secondary winding on the utility transformer that is 240V, with a tap in the center which is grounded.  The tap is half way so it is 120V to each hot conductor.  If the neutral connection is lost, you still have 240V between the hot conductors, and all the 120V things in your house will be put in series.  For example, a couple light fixtures on 2 separate circuit breakers might be on the two opposite phases.  When the neutral is lost to the utility, there is still a connection of the neutral's of the lights, so you'll have the two lights in series and connected to 240V.  Each light will not have 240V though.  If the load on each phase were the same, removing the neutral will still leave 120V on each side.  That isn't likely, so one phase will get more than 120V (and generally cause damage) and the other phase will be less than 120V, and they will add to 240V.  It would be impossible for it to be so unbalanced that one phase would be 240V and the other would be 0.
742046
For three phase AC powered loads, three separate power lines provide power to the load. The voltage waveforms on these three lines differ only in their timing, or phase relationship. A fourth wire may provide a neutral connection to the load. In the case of balanced loads, where the current in each of the three phases is equal, the current in the neutral wire will be zero. The neutral wire may therefore be eliminated, as it is not necessary for the purpose of carrying current. The vector sum of the currents drawn from the three phase lines will be zero with a balanced load. A non-zero sum of the current indicates an unbalanced load and that a current is returning to the generator, or current source, via an unintended path. This is the ground fault current.\n\nThe ground fault current for a three-phase system, without neutral, may be measured by performing a vector summation of the phase currents. This summation may be performed by a current sensing transformer with the phase currents passing through the common aperture in parallel. The magnetic field induced in the transformer core is then the vector sum of the three individual phase currents and the voltage induced in the secondary winding placed on the transformer provides a signal representing the vector sum of the currents, the ground fault current.\n\nThe electrical characteristics of ground faults in solidly grounded WYE systems allow for simple detection of ground currents by monitoring the phase and neutral currents for a simple unbalance in those currents. The principle is that the current going to the load on the normal phase and neutral conductors should return via those same conductors. Any missing current is deemed a fault to ground on the load side of the detector and, when that unbalance exceeds a set threshold, a ground fault is determined. The basic ways of measuring this unbalance for solidly grounded four-wire systems use one ground sensor surrounding the phase and neutral conductors, four individual current transformers connected in a WYE configuration, or four voltage sources connected in a delta configuration.