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From USCG Surge Protective Devices Onboard Vessels
A marine casualty investigation of two separate stateroom fires onboard a U.S. Flag Container ship revealed that the sources of the fires were attributed to the use of SPDs plugged into a lighting circuit. It was discovered that a ground had developed on another circuit that was connected to the same ...
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Correct, coil noise is generated in the windings of the motor because of Pulse Width Modulation (PWM) driving current. Different frequencies of modulation cause corresponding sound frequencies (may create half or double frequency oscillations as well).
To change the speed of an electric motor, PWM is required to regulate voltage in DC motors and generate ...
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Something like this?
http://www.browninnovations.com/sound-dome/single-localizer-sound-dome
As others have said, it is a speaker with a parabolic reflector to direct the sound down at the listener. You can make your own fairly easily: http://www.instructables.com/id/umbrelAudio-Sound-Dome-Umbrella/
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The difference is due to the strongest force in the universe: Marketing.
Both devices are linear regulators. This means they take a high and varying voltage in, and produce a low and steady ("regulated") voltage out. These type of regulators are totally powered from the input voltage, and adjust how much current they allow to pass from the input to the ...
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With a description as vague as that, it was probably a parabolic reflector with a speaker at its focus. Pointed straight down, the "beam" of acoustic energy would be reflected from the floor right back into the "bell", with remarkably little leakage out the sides.
A reflector with a diameter of 4-5 feet would be directional for frequencies down in the ...
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Not too sure if you will be able to find datasheet for specific cell phone. These are proprietary information and mobile phone manufactures usually don’t share this type of information in public for various reasons. Depending on the business needs you should contact the vendors directly and seek datasheet, which might be obtained under a non-disclosure ...
answered Jun 16 '15 at 23:13
Mahendra Gunawardena
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6
There are cases where DC power generation is superior to AC.
If it's going to be transmitted by DC, and you can generate at the transmission voltage, or you can step up the voltage to transmission levels without too much loss, DC is superior.
If your load is DC, and is close to your generator (in space and in voltage), DC is superior.
Both of these assume ...
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You are correct, getting oil pressure will require an electric motor as your source of rotation, potentially a gear box to slow that rotation down, and the pump itself. You'll also need a reservoir to store the non-pressurized oil and probably a filter to keep the oil clean (dirty oil will damage your components.)
If you're new to the world of hydraulics, ...
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At a very high level linear low-dropout regulators have a pass transistor, an operational amplifier, a resistor divider circuit feeding the operational amplifier and VREF. The operational amplifier is an error amplifier. In short the pass transistor acts as a variable resistor which controls the current flow.
Block diagram for linear & low dropout ...
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One way to think of MEMS is regular mechanical systems, but at a very small scale. Often these tiny systems are fabricated using technology developed for making silicon electronic chips, like nanometer-scale photolithography and etching.
However, describing MEMS as just downscaled regular mechanical systems is doing the concept injustice.
Various physical ...
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Because this question has proven a little more derisive than I had anticipated (where's that engineering sense of fun/humour?)- I thought I'd attempt an answer as well, if only to prove it's an engineering question which can be answered using the engineering method; although hopefully someone using something more than Google will be able to chip in with a ...
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Pretty much all electric motors demand a lot more power for starting from a dead stop than for generating motion in a steady state. There are a whole lot of schemes for smoothing out this 'inrush current' demand, either from the electrical side or from the mechanical side (by decoupling the load and gradually re-connecting it once the motor spins up.) The ...
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You did not specify what materials you are working with and neither the dimensions. I made some assumptions.
First of all, the coolant circuit is likely driven by a pump. Therefore you need to know the flow rate $\dot{Q}$ the pressure needed on the pressure side. You can get more information here.
For your specific setup to cool the PSU you have pressure ...
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You are combining two concepts.
A sensor is any device that responds to a desired signal in some manner to produce an output that is used to detect the presence of the desired signal or to allow some desired attribute of the signal to be measured - such as its amplitude, frequency, rate of change, relative phase, etc. Even colour, temperature, dimensions, ...
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The pressure requirement could also be to raise the temperature at which the water boils. The boiling point of water depends on the pressure it's at; higher pressure raises the boiling point, as the following image shows.
As you can see, water at atmospheric pressure boils at 100 C, but water at 3 bars boils at about 130 C. When water starts to boil, it ...
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When chemical/photovoltaic power generation is readily available, versus electromagnetic (based on mechanical power).
If locally you have sources of mechanical power (wind turbines, steam turbines, diesel motor, hybrid car gasoline motor, etc) you use a generator and either rectify the AC to DC (with losses) or adapt your recipient devices to accept AC, or ...
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A perfect ideal transformer converts some combination of Volts and Amps going into it, to some other combination of Volts and Amps coming out but a the same power. Put another ways (Volts in)(Amps in) = (Volts out)(Amps out).
By this logic, it is the power used by the bulb that matters. Just because the transformer could have supplied 300 W (and then ...
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The answer is #1, with a bit of an asterisk.
If the bulb pulls 50 watts as it's rated, the current (power divided by voltage) will be 4.17 amps. We know that anywhere in a closed circuit, the current is the same, so the power supply is outputting 4.17 amps as well (assuming it is attached to only one light bulb.)
So, if your power supply is outputting 12 ...
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Because it is not a power cable (Q1) using power connectors (Q2).
BNC cable has a solid conductor and a ground braid to electrically shield and mechanically protect the conductor.
Electrical reason: Some ground braids are made of steel, which is not as good a conductor as copper, so voltage losses to the wire would be higher than copper wire. Basically, ...
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Originally the spiral shaped devices were fitted to the earth wires on top of pylons as vibration dampers (the very top single wire on pylons is the earth wire). It was however noted that they also had the effect of discouraging birds from landing on the wires. Therefore the spiral bird diverters can be used as dual purpose devices. Keeping birds away and ...
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MEMS is a semiconductor based process that can create miniature structures in silicon. When these structures (sensors) are subjected to mechanical stresses (pressure, acceleration, yaw etc) they are able generate electrical signals. These signals are conditioned using an Application Specific Integrated Circuit (ASIC) to create a sensor system.
Below are ...
answered Nov 15 '15 at 14:34
Mahendra Gunawardena
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3
the iron structure(s) inside a generator serve the purpose of minimizing flux leakage, which maximizes the utilization of the magnetic field in generating electricity. One of the ways in which they accomplish this is by furnishing what is called a return path for the lines of force, so as to "close" the magnetic circuit inside the device.
For things ...
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Each channel can be set to be triggered high or low.
See User Manual
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Make sure that the 12V supply is capable of sourcing sufficient current. This the source that powers the output A & B. The 5V input supply is most likely to power the logic circuitry. On PCB board 12V supply power supply should be routed to the H-bridge which will provide the voltage to both Output A and Output B as mentioned above.
Also when you are ...
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Typically, the max is 100mW (20dBm). You can refer to an example wifi chip datasheet (This one is used in many mobile phones with Snapdragon processor) -
https://developer.qualcomm.com/download/sd410/wcn3620-wireless-connectivity-ic-device-specification.pdf
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SSR or Solid State Relay is what you are after. You should be able to trigger this one right off the 3 volt rpi gpio. FOTEK SSR-40DA. Here is a DC one CPC1709J. Use a voltage divider or zener diode so you dont exceed the 1.2v input. You will likely need a heat sink.
You may want to consider using a mosfet instead and running higher frequency. Higher ...
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Regarding questions 2 and 3, I think you need to look deeper in the chemistry, reactivity, and heat transfer characteristics of Nitrogen.
1) It is not a noble gas. It is reactive, and you benefit from this reactivity each time you eat a plant protein.
2) I have not designed a railgun and I don't have much sense of the thermal inefficiencies here. But I ...
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DSP is relevant to any engineering field that involves gathering data and/or controlling something. That includes almost all robotics applications.
It's not quite clear just from the title what "Power electronics and drive" means. "Power electronics" could be anything from a 20W amplifier driving a motor, through a few MW for transport applications (e.g. ...
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Here is a good link on Capacitors. Capacitor is a energy storage device. Capacitor can act like a battery. Stored energy is discharged to a device like an LED. Take a look at this capacitor battery LED resistor animation.
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We have a test rig that works something like this, to heat up small objects (typically cubes of material with sides a few mm long) to about 1000C fairly quickly.
The heat source is a "tube" of ordinary (and fairly cheap) tungsten-halogen car headlight bulbs surrounding the test piece, rated 12V 55W each, with home made parabolic reflectors covered in ...
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