Recent content by SirAskalot

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    Cons of Stopping shaft connected to gearbox

    First of all, a gearbox only changes the speed. So to determine if you need one you have to look at the shaft rotation speed in relation to the generator nominal speed. Problem is what are you going to do with the electricity produced. It is intermittent so you may want to store it in a...
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    Please help designing a specific electromagnet

    You have two equations and two unknowns; L , A. Should be basic algebra. R = rho * L / A L = 500 * "circumference of one turn" <---- given by geometry of your coil/core
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    ANSYS Maxwell Impedance Matrix

    If you are unsure of how to interpret the results for three conductors. Remove one current/voltage source and simulate the system as a two circuit system, e.g. current in circuit 1 and 2. This will give you the case as in the documentation, with L11, L12, R11,R12, … ,R21. Then apply current to...
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    DOL Motor Starter can support 160KW, 1000KVA Pump?

    It mainly depends on the grid it is connected to. The problem faced with starting is the voltage drop in the cables/grid becomes to large due to the large starting current. Thus a reduced terminal voltage will reduce the output torque of the motor, and it may not be enough to overcome the load...
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    Cons of Stopping shaft connected to gearbox

    I dont understand what you mean, so you have to elaborate some more. What is the prime mover of the shaft? What is it connected to? Why do you need a gear box? Do you need to break the shaft every 1 minute? Do you want to generate electricity from the rotating/kinetic energy stored in the shaft?
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    Very silly question regarding DC motor

    I would try it out. Set the voltage limit "low" at first, measure the current and maybe the temperature of the motor (simple PT100 element or similar, its also very fun an interesting to just experience it). Measure the current with a ammeter or oscilloscope (if available. Current rise/peak may...
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    Very silly question regarding DC motor

    From my experience, it is neither the voltage or current that breaks the machine, it is long exposure to high temperatures. That is, the insulation degrades due to the high temperatures. Current are of course the central factor in the temperature distribution in the machine, but thanks to the...
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    Servo Mechanism to initiate movement of an electric motor trolley

    Choice of motor also depends on your power source (i.e. battery, fuel cell, generator), load torque (you have said 400 Nm, based on what?), power ( what speed do you want?, air drag coefficient etc.) and speed/gear ratio. A DC motor might be the simplest motor to control, so it would be a good...
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    Servo Mechanism to initiate movement of an electric motor trolley

    Are you looking for advice on selecting a motor (drive system), or the control part of the system, i.e. the sensing of motion/force in a direction?
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    Faraday's law

    Look up "Lenz law"; "An induced electromotive force (emf) always gives rise to a current whose magnetic field opposes the original change in magnetic flux."
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    Motor circuit excessive heat

    You mentioned that you changed the gear ratio. This would change the load torque on the motor, from low to high. And since it does not run/spin the load torque is higher than the torque produced by the motor. http://en.wikipedia.org/wiki/Gear_ratio Torque is proportional to current and it...
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    Induction coils and contact materials

    2500 degrees Celcius are some serious temperature! What is the application if I may ask? Shielding can be done in two ways. Either by conducting the magnetic flux trough a high permeability conductor ( that is, the flux is confined to inside of the material) or using a high electrical...
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    Generator selection help

    Well, torque is not drawn from anything. But the generator creates a "counter torque" acting in the opposite direction than the torque created by your motor. A equal torque and opposing torque will prevent a acceleration (Newtons laws, right?). As efficient as possible is one of the biggest...
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    Can we use earth as neutral?

    The "quality" of your voltage depends on how the transformer is grounded. In a floating neutral point or delta connected secondary a phase-ground connection would not give the same function as a phase-phase connection. But it would still be a potential difference between one phase and ground...
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    Generator selection help

    Just to clarify. Are you designing a internal combustion engine, the one you refers to as the motor, or are you designing a electrical motor? Anyway, what "type of electricity" do you want? AC or DC? 50 or 60 Hz? What "grid/network" are you going to supply? According to conservation of energy...
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