# Tag Info

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Conceptually, you want something like this: simulate this circuit – Schematic created using CircuitLab When you turn M1 on, the current rises in the solenoid, charging the magnetic field up. When you turn it off, the current decreases towards zero, flowing through the diode or upper MOSFET. If you PWM fast enough relative to the inductance, the ...

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In your example, the total loss dissipated in heat corresponds to the sum of individual losses in the resistors. You correctly calculate them with $P_R=I_{rms}^2R$ with $R$ the considered resistance and $I$ the current in the resistor. I simulated the below sketch with a 100-$\Omega$ resistance across the capacitor. The source delivers 10 V peak at a ...

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Quasi-square-wave quasi-resonant converters also called QR converters are popular structures in ac-dc chargers for notebooks and portable electronics. They are popular because: they operate permanently in discontinuous conduction mode (DCM). they remain a first-order system easy to stabilize despite a right-half-plane zero located in high frequency (versus ...

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The Poynting vector $\bf S$ is given by $${\bf S} = {\bf E}\times{\bf H}$$ The magnitude of the Poynting vector gives the intensity of the electromagnetic wave. That is the, the power per unit area. To get the received power from this you must average over time and integrate $\bf S$ over the effective aperture area of your antenna, multiplying for the ...

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When the new load comes onto the grid, a large load current will flow through it. This load current has to be sourced by the generators. The increased current in the generators throws an increased torque requirement onto the engine or turbine that's driving the generators. As the engine control at that instant has no way of knowing that more torque is ...

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All resistors have the same efficiency, they convert the dissipated power to heat. The answer depends on whether you want to heat air or a surface. A resistor that is mounted to the chassis with screws will transfer the heat to a surface more efficiently. A resistor with poor contact to the surface, will mostly heat the air. Chassis mount resistor: https://...

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A silicon-controlled rectifier (SCR) is a type of thyristor. Another type of thyristors is the Gate turn-off thyristor (GTO). A diode base rectifier is called an uncontrolled rectifier. With the use of SCRs (among other devices) you get a controlled rectifier. The benefits of a controlled rectifier is that you can control the load voltage and power factor. ...

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1) Around but less than 4 days (500 Wh / 5 W = 100 hours = 4 days). Because the conversion efficiency is less than 100%, you will not get the full time. 2) it won't hurt the battery itself but who knows what the 5V circuit will do? In any event it is not adviseable to exceed the limits of the stuff you buy unless you are willing to take risk. Most likely ...

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If this is a Cube-sat application, For aerospace I recall the two major concerns were reliability and efficiency. For reliability in a low air density environment and also for efficiency, you want the injected heat / lost heat ratio to be high, I expect. Thus the ratio of thermal resistance ratio for battery insulation to heater conduction to batteries ...

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It's not a good idea to replace the voltage levels that a system is expecting. Unless you're modding the synthesizer to accept your GND, 10V and 20V. Audio systems generally have a bipolar supply because it's necessary for the opamps inside to properly amplify an AC signal ( you can't amplify a negative voltage if your supply only has a positive rail). ...

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RL is just a bleed resistor to discharge C2. So, when someone disassembles the toaster, they don't get zapped. To discharge to a safe level in about a minute: 27k. Power = 160^2/27k = ~ 1W, this is probably too much power to waste. Maybe 100k? Need to know the coil resistance to determine appropriate values for R1 and R2. Edit 1: I wouldn't call J3 "AC ...

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The definition of the aperture of the antenna is The aperture is defined as the area, oriented perpendicular to the direction of an incoming electromagnetic wave, which would intercept the same amount of power from that wave as is produced by the antenna receiving it. (source) So if you know the aperture of the antenna, you already know, by definition, ...

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A typical flyback design From my understanding, if we go above the primary peak power, the transformer will saturate. How this CCM mode overcome that? It's better to talk about reaching a peak in primary current rather than a peak in primary power because it's an excess of current that creates core saturation. So, if you define $I_{MAX}$ as the ...

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I'm not 100% sure, but I believe that the reason for the unusual earthing arrangements on french and german plugs is backwards compatibility with existing installations. Appliances can be categorised into 3 categories. Class 0: no earth connection, not "single fault safe" (now banned in most first-world countries) Class 1: "single fault safe" only if an ...

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Once someone told me they are safer because the ground connects first, but this is also nonsense as the order of connection depends on the size of the plugs alone and not where they are You are right. The ground pin could be on the cord itself. But it is how it is. But this is a generic argument, looking at may available type sockets and plugs used ...

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It seems that you are asking about the power used by a fetal doppler device such as a baby heart monitor. It says in the instruction book that the power output is 20 mW/ square centimeter ... That tells you that the mechanical or sonic energy output by the device will be 20 mW/cm2. Therefore the total output power will be area × 20 mW where the ...

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The outside of the element is a metal tube, which must be earthed for safety. Inside that is a length of resistance wire, such as a nichrome alloy. The gap between the resistance wire and the outer tube is filled with heatproof mineral insulation. As the element gets old, the outer tube can develop holes, letting water in. At this point, the element ...

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you wanted to calculated the real power You would add the powers. You would calculate the DC power and you would calculate the AC power and add the two together.

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The size of the wire you need depends on the load connected to the extension cable, not the source providing power to it. The ampacity of the wire will not change based on the voltage of your electrical system, but the power handling is directly tied to it. If you are expecting to get "nearly" 1200w over a 6M cable at 230V, you need a wire that is rated to ...

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One way to define voltage (electrostatic potential) is the answer to the question "how much energy would it take to put an element of charge at this location?". So if charge enters a circuit element with a certain amount of energy, and leaves with less energy, the energy of the charge must have gone somewhere in the element. On the other hand, if charge ...

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Note that not all power transistors have the case or tab connected to the collector, some RF power transistors have the case connected to the emitter. This provides a lower inductance path to RF ground, which in an RF amplifier is critical to maximize gain.

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