0
Electrical Wiring
Ask questions here about proper wiring and electrical installation here.
4,935 Questions
What is conductor size for a 45kw 3 phase 415 volt induction motor at 50 meters?
To answer this question, wire size is rated in the amount of amperage that it can legally carry. The formula to find amperage when the HP is known is I = HP x 746/1.73 x E x %eff x pf.
A standard motor's efficiency between 5 to 100 HP is .84 to .91.
A standard motor's power factor between 10 to 100 HP is .86 to .92.
Amps = 60 x 746 = 45000 = 45000/ 1.73 x 415 x .87 x .87 = 45000/718 = 62.7 amps.
The electrical code states that a motor conductor has to be rated at 125% of the motors full load amperage. 62.7 x 125% = 78 amps
A #4 copper conductor with an insulation factor of 75 or 90 degrees C is rated at 85 and 95 amps respectively.
A #3 copper conductor will limit the voltage drop to 2% or less when supplying 78 amps for 50 metres on a 415 volt system.
How do you make your weapon special in oblivion?
There are two ways to get your weapon enchanted or "special." The sigil stones you get from closing oblivion gates have two enchantments on them: an offesive one for your weapon or a defensive one for your armor. If you are the Arch-Mage, then you can use the Altar of Enchanting to enchant your weapon, provided you have a filled soul gem available.
The standard method of speed control of three-phase motors is a VFD or variable frequency drive. Standard drives need AC power though. A quick look through ABB's catalog shows an ACS-550 drive good for 400hp weighs 504 lbs. and is 79 inches tall. Oops, not very practical for an electric car. The standard control algorithm for these drives would not have the right "feel" for an electric car as well. The accel/decel curves are all wrong. Do you realize that a 400 hp, 460V motor draws over 470 Amps? That's a whopping 374 Kw! Realistically, you are in the realm of $1,200-a-piece IGBT modules, six of them, with a custom designed, microprocessor-controlled driver. Oh, and one electronic engineer experienced in high-power power conversion design, and a software engineer too. The modules will probably have to be liquid-cooled. A quick calculation shows a bank of 54 12V lead-acid batteries each rated at 65 A/H would run this motor at full power for six minutes. Hope you have some exotic secret batteries in mind...
Will a pioneer tau-11 work as a FM transmitter?
The Pioneer Tau-11 is a switching box and mic preamp for mixing and controlling a
pair of tape decks.
If you turn it over and read all the fine print on the bottom ... or look through the
instruction book if you still have it ... somewhere you'll find a little sticker or a
half-page saying that the unit complies with the requirements of "FCC Part-15".
That's a rule imposed on manufactured electronics that puts strict limits on the
amount of signal they're allowed to radiate.
So no, the Tau-11 isn't built to be a radio transmitter, and before it can be sold
in the US, it's required by law to be incapable of doing that job.
The simplest explanation (and therefore not completely accurate, but it will help you understand what happens) is that as the frequency of an AC signal increases the less able a wire is to contain it.
- at very low frequencies, including those of powerlines, the current flows easily through the entire diameter of the wire
- at intermediate frequencies, up to about the AM radio band, the current avoids the center of the wire, only flowing through its surface
- at high frequencies, including those used for TV, a significant amount of the AC signal escapes from a wire as electromagnetic radiation - the shield on a coaxial cable "reflects" this electromagnetic radiation back to the center conductor, preventing its loss
- at microwave frequencies AC will not follow a wire at all and the electromagnetic radiation is directed around through metal pipes called waveguides (analogous to a coaxial cable but without a center conductor, only the outer shield to reflect the electromagnetic radiation)
Does the power factor in three phase system depend on the phase sequence?
No. It depends on the inductive and capacitive reactance of the load.
How does an astable circuit work?
astable network means it has only one stable state.so the circuit need trigger input to change to another stage and it automatically changes to the previous stage when the process completed with the use of the capacitor.
How made the Jacobs ladder electricity?
I don't know, but i do know you need a massive @ss transformer!
How to generate power from piezoelectricity?
mainly Piezoelectric crystal is a transducer which convert mechanical energy to electrical energy.
piezoelectricity material generate power, when we compress or extended its shape.
means that when we change in dimension of material then the voltage produced between atoms of material by which power generate.
How can I tell if an extension cord is for outdoor use?
Look on the cord for the designation SOW. This type of outdoor flexible cord is for use wet, damp or dry locations and is approved for extra hard usage.The letters mean, S - severe service cord, O - oil resistant outer jacket material and W - (CSA) weather and water resistant (approved for indoor and outdoor use)
How do you convert a three phase power supply into single phase power supply?
You can take three separate single-phase circuits from a 3-ph generator. Just use one of the live wires plus the neutral to make a single-phase supply.
<<>>
A three phase generator does not have to be converted to single phase. In electrical terminology any two legs from a three phase system are classed as single phase. No matter what voltage the generator is producing, L1 - L2, L2 - L3, L3 - L1 are classed as single phase legs along with L1 - N, L2 - N, L3 - N.
If the generator output voltage is not the voltage that you are looking for use any two legs of the generators output voltage and use a transformer to obtain the voltage that you need.
How do you get rid of unwanted eddy currents?
To eliminate eddy currents you can cut small slits in metals. This will prevent larger eddy currents from occurring. Placing insulators between small laminations can also help to protect against eddy currents.
Would voltage in a three phase supply change if neutral wire is disconnected?
No, The voltage will not change. The neutral is basically a ground and is used in conjunction with the phases to create another voltage and act as the return line in an electrical system. "Depending on the system that you have". If you have a 480 volt and used a neutral with it you would have 240 or 277 volt. The 277 volt is what is normally used in office lighting. If you have a 208 or 240 three phase system using a neutral you end up with the 120 volts that is used for just about all normal lighting, receptacles and general use devices used everyday.
Additional Answer
While the supply voltage wouldn't change, the voltage across each phase of an unbalanced load may change if that load is unbalanced.
Wiring sound and light define the following polarity of the screw colors brass bronze silver green?
Brass (or bronze) is the "hot" wire, (Black, red, or blue) silver is for the neutral (the white wire) and green is for, well, the green or bare wire
Electrical circuits, to limit the maximum current flow. Fuses will "blow", or burn out, and cause an open circuit, to stop the flow of current when it could potentially damage a circuit, system, or device.
What is a bad connection in an electrical circuit called?
"A wiring fault" which - depending on the actual behavior of the bad connection - might also be described as "an intermittent fault", "a high resistance fault", or a combination of all three terms.
For example: "An intermittent, high resistance wiring fault".
The power consumed can be calculated directly from the current draw, voltage, and power factor: (3A) x (400v line to line) x (sqrt(3)) x (.9pf) = 1.87kW. This would be a reasonable value for a 3hp motor that is not running under full load (the motor may be slightly over-sized for this application). The size of the motor is irrelevant to this calculation, although it shows that it is running at ~85% of its capability.
Another Answer
Since a motor is a balanced load, we use the following equation to find its input power:
power = 1.732 x line voltage x line current x power factor.
So, in your example,
power = 1.732 x 400 x 3 x 0.9 = 1870 W
Obviously, it cannot be delivering 2200 W when its input is just 1870 W. However, to determine its output power you will need to determine its efficiency at that input.
What colour are the phase neutral and earth cores flexible cords?
Flexible cord colours are, White for neutral and Green for ground.
AnswerIt depends on the standards used in your country. The above answer refers to North America. In Europe, the colours are brown for the line (not 'phase'!) conductor, blue for the neutral conductor, and green/yellow stripe for the earth (ground) conductor. For European three-phase systems, the lines are coloured brown, black, and grey.
For the UK11 kV is the standard three-phase h.v. distribution voltage in the UK, where it is a line voltage (i.e. it is the voltage measured between any pair of the three line conductors). A single-phase distribution transformer is connected between any two lines, so 'single-phase 11-kV' is simply a connection made between any two lines of an 11-kV three-phase system.
As the primary windings of three-phase 11-kV distribution transformers are delta (3-wire) connected, the primary phase voltage is numerically equal to the primary line voltage (11 kV).
On a 220 volt electric motor which is the neutral wire L1 L2 or L3?
If the motor wire numbers are L1, L2 and L3, it is not a single phase motor. It is a three phase motor. Also for future reference, a 220 volt single phase motor does not use a neutral.
It will still be 4.5V except your meter will either indicate "-" for negative or normally no indication at all for positive. If your meter indicates both negative and positive, you will see "+".
There are many facts about rusting including the fact that it is a chemical process. Oxygen is also involved in this process.
Definition of digital devices?
Digital electronics represent signals by discrete bands of analog levels, rather than by a continuous range. All levels within a band represent the same signal state. Relatively small changes to the analog signal levels due to manufacturing tolerance, signal attenuation or parasitic noise do not leave the discrete envelope, and as a result are ignored by signal state sensing circuitry.
In most cases the number of these states is two, and they are represented by two voltage bands: one near a defenitions
reference value (typically termed as "ground" or zero volts) and a value near the supply voltage, corresponding to the "false" ("0") and "true" ("1") values of the Boolean domain respectively.
Digital techniques are useful because it is easier to get an electronic device to switch into one of a number of known states than to accurately reproduce a continuous range of values.
Digital electronic circuits are usually made from large assemblies of logic gates, simple electronic representations of Boolean logic functions
Can 400V motor run on 415V supply?
Probably; it is a difference of less than 4%. And since the voltage is slightly too low, you won't burn the motor - having too high a voltage is more risky.
