The device which disconnects the start winding in some split-phase motor circuits after a present speed is?
351810
The thermostat is a heat sensor. The commutator is part of the rotor. The brush spring keeps constant pressure on the brush against the rotor, \nThat leaves.... the relay.\nIn small motors a centrifugal switch is used. It's mounted on the rotor shaft. When it reaches speed, the outward force opens the switch and disconnects the start windings.\nIn larger motors like 100 horse power and up, a "part winding start" can be used. Only a small part of the windings are used to start the motors. The starter box has a timer that triggers a relay that engages the rest of the windings when the speed is up.
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The device electrically separates the water heater from the household piping. \nIt also provides a convenient way to disconnect the piping for removal or servicing of an appliance, such as a water heater or water softener.\n\nRefer the link for pictures
932280
When supplying a branch circuit with more than one live conductor, each live conductor must be protected by a breaker pole. To ensure that all live conductors are interrupted when any pole trips, a "common trip" breaker must be used. These may either contain two or three tripping mechanisms within one case, or for small breakers, may externally tie the poles together via their operating handles. Two pole common trip breakers are common on 120/240 volt systems where 240 volt loads (including major appliances or further distribution boards) span the two out-of-phase live wires. Three pole common trip breakers are typically used to supply three phase power to large motors or further distribution boards.\n\nMCB (Miniature Circuit Breaker)—rated current not more than 100 A. Trip characteristics normally not adjustable. Thermal or thermal-magnetic operation. \nThe overload relay  consists of a coil, a plunger, a dashpot, and a pair \nof switch contacts. The plunger is attached to a disk suspended in an oil-filled chamber (dashpot). The coil connects in series with an associated 440-volt motor supply circuit and the switch contacts are in a 115-volt start-and-run circuit for the motor. \n\nDuring normal operation, the magnetic flux induced by the coil is not great enough to cause an appreciable movement of the plunger. However, if an overload of sufficient magnitude and duration occurs, the increased current through the coil draws the plunger upward. \n\nWhen the plunger and disk reach the end of their upward travel, the normally closed contacts open in the 115-volt start-and-run circuit, de-energizing the motor contactor which opens the 440-volt motor supply circuit. With the motor circuit open, the overload relay plunger drops and the relay resets. \n\nSince the dashpot retards upward movement of the plunger disk, the circuit does not break instantaneously during an overload. Two conditions determine the delay time: (1) the size of the orifice in the plunger disk through which the oil must pass and (2) the magnitude of the overload (strength of the magnetic field).
1075481
Hotwire around it in the circuit.  Cut the lead feeding into the filter after the jumper.\nJust like bypassing a sensor in a burglar alarm system.
807450
For a wye-connected machine:\nThe phase voltage (measured between a-b, b-c, or a-c) is (SQRT(3))* the line voltage (a-n, b-n, or c-n). In this case, connect your invertor across a-n, b-n, c-n (this may mean breaking the "common" neutral connection).\n\nFor a delta-connected machine:\nThe phase voltage equals the line voltage. In this case, connect your invertor across a-b, b-c, and a-c.\n\nWhich polarity you choose for the three connections will determine rotation - make sure your resultant rotation matches that on the machine nameplate, or you'll likely burn it up due to insufficient cooling...
987674
Those are called "ferrites".  You can learn more about them from a company called "Fair-rite" (I put their link down below).  A ferrite is really nothing more than a magnet, but one specially tuned depending on the frequency of signal running down the cable, or the current if the cable is a power cable.\n\nElectro magnetic interference (EMI) is all around us, especially with all the electronic devices we have running in the modern home.  EMI flies through the air and, when it contacts something metalic, it "runs along" that metalic line.  In the case of a cable, imagine the clean signal picking up "fuzz" as it runs down the line.  That's pretty much what happens.  A ferrite stops the "fuzz" from getting through to the end of the cable, thus making the signal much cleaner when the end device gets to it.  On a power cord, the ferrite helps prevent too much EMI from leaking out at the end and interfering with the device that the power is for.\n\nI should mention that a ferrite is always "optional" on a line, in other words the cable will work without one.  However, ferrites aren't expensive and they do help with the signal, so most companies will just add one on to the product just in case.
2647
The PD will decrease as the current passing through it will drop due to current division
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One really needs the manufacturers part number to get that information. If the dataplate is gone, you can ohm out the windings, and through the process of elimination determine the  proper connections. You might want to check out the stepper motor seciton at CNC zone.\nhttp://www.cnczone.com/forums/forumdisplay.php?f=193
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It appears that you have asked about the synchronous motors that are used to run flourmills. \n\nThese motors can be initiated at a particular RPM only. For that, a small induction motor runs the synchronous motor and brings it to a particular RPM. As soon as it happens, the main synchronous motor is switched on.\n\nYou might have seen a lever switch for this setup… the operator operates the lever to the upper position for starting induction motor… then on assessing that the motor has reached the minimum required RPM he brings down the lever to the downward position for switching on the main synchronous motor.
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This is a magnetic flywheel.  The spinning magnets will induce a voltage across the coil of wire.  If you draw current from the wire, that current will induce a magnetic field which will exert a torque on the magnets, slowing them down.  The total electrical energy you can get out of the system will never exceed the initial kinetic energy of the rotating magnets.\n\nThe thing slowing down the magnets is not friction, it's an electromagnetic force, and even if you eliminate friction completely, the magnetic torque will spin down your magnets quite handily as soon as you start extracting energy from the system.
895254
Running an electric motor "backwards" generates electricity.
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In order to know how 3-phases of voltage (separated by 120 degrees) are produced, one would have to know how a 3-phase generator works and know a bit about electromagnetic theory.\n\nIn nearly all power plants (except for some wind turbines), a 3-phase synchronous generator is used.  This type of generator has one or more wire coils attached to the shaft (the rotor) and a set of coils evenly spaced around the frame surrounding the shaft (this area is known as the stator).\n\nThe coils on the rotor are energized by a small DC source and become constant electromagnets with north/south poles determined by the direction in which the current flows.  The shaft is moved by a source of mechanical power.  Generally a steam turbine is used where the steam is heated from some source of energy like coal, natural gas, nuclear etc.\n\nSo as you can imagine, we have one or more electrogmagnets attached to a shaft being rotated by a turbine.  Remember that these rotating electromagnets are inside the evenly spaced windings on the stator.  Faraday's law states that a time-changing magnetic flux in a coil will produce a voltage in that coil.  Since the rotor electromagnets are constantly changing position relative to the stator coils, the magnetic flux seen by the stator coils is also constantly changing.  The wire coils on the stator frame are evenly spaced such that the induced voltage waveforms will be spaced 120 degrees apart.\n\nSo, we then have sinusoidal voltage waveforms produced on the stator coils such that they are 120 degrees apart.  These coils on the stator are then connected in either wye or delta configurations and carefully hooked up to the power grid.\n\nSo that is a somewhat simplified view of what is happening.  There are various other complications that I have not mentioned, but are not important in getting the general idea.  You might be able to find a nice 3-phase electric generator animation on howstuffworks.com or Wikipedia.
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A choke is an inductor designed to have a high reactance to a particular frequency when used in a signal-carrying circuit. They are inductances that isolate AC frequency currents from certain areas of a radio circuit. Chokes depend upon the property of self-inductance for their operation. They are used to block alternating current while passing direct current. Common-mode choke coils are useful in a wide range of prevention of electromagnetic interference (EMI) and radio frequency interference (RFI) from power supply lines and for prevention of malfunctioning of electronic equipment.
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You might start by contacting the power company.  If you have concerns about eletromagnetic interference, they should be willing to help you.
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try this website http://www.howstuffworks.com/search.php?search=electrical%20motors%20and%20generators&ref=hpaw&page_ref=http://www.howstuffworks.com/
448481
The concept is to build an electromagnet that cuts the circuit when energised. This produce a buzzing effect
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the chances are that if the motor has only one capacitor ( capacitor run only) then the run capacitor is faulty and if the motor happens to be spinning in one direction it will get up to speed in that direction. Answer buy a new capacitor. if the motor has two capacitors (capacitor start/run) the chances are the motor has serious problems because the rotation of the motor is dependent on the the terminal connections.