Emi Definition and 39 Threads

As i recently came to know that the energy is not travelled in the wire infect it is travelled in the space around the wire in the electrical and magnetic field (thanks to varitasium for his video) so my question is particularly related to the IC fabrication. In IC fabrication we have...

I am new to EMI modeling and just looking into it. I would like to create a circuit schematic to represent the inductive and capacitive coupling paths in one schematic. All that I've been able to find online is references discussing each independently. Is this the best approach if you want to...

I am starting the input filter design for a converter and only have the voltage and power specs. It will be the input filter to other converters on a parallel bus, so I could look at the datasheets for those and get some specs there. I do not have any information from the input converter to this...

Let's assume that I have have one conductor carrying current to the load in one direction and the return line with current in the opposite direction from the load. If the current has high di/dt due to switching, may have EMI issues with nearby circuits. I know that I can put a "ground" plane on...

This is an excerpt from a high school physics textbook. I don't understand the possible reason behind this statement. If we change something in the circuit say for example add a resistor , the current and hence the flux should change. Then why/how is this statement true?

I have done the maths to work out the Induced Voltage on a communication cable, from a bunch of 3 phase circuits in a panel - with the minimum distance between them I calculated it to be about 1.5nV; but for a larger system where there could be larger loads on the cables I was thinking about...

Dear forumers, I need a 50hz 250VAC power line filter for an EMI shielding faraday cage. The filter should work between 100khz and 20ghz, attenuation should be >=60dB between 1mhz - 5ghz. Regular power line EMI filters like this don't seem to go that high (only up to a few hundreds of mhz...

Homework Statement More than one options may be correct . Homework EquationsThe Attempt at a Solution [/B] Options a) and c) are correct . But I don't understand how non magnetic metal reacts to the magnetic field . Is it in some way related to ferromagnetism ? But then either both b)...

Does EMI filter still work if you live near a base station which produces dirty electricity? Or EMI filter only filter the dirty electricity which would have been generated from your power circuit if w/o EMI filter?

I have a circuit which can produce bursts of 500V. When I did this circuit, The 2.2 mH is burning. I want to know whether do we need to take care the power rating of inductor? After the test I tried the experiment without inductor too. I have used 2.2ohm, 1W resistor. That too started to burn...

I need to know how to couple noise due to chattering of relay? I have seen the below method to couple. But I want more detailed circuit to do this. Please help me. Also I want to know where the tremendous amount of EMI can be seen ? Is it across the coil of relay?

Hi, With all the various RF coming from things in my own house (cell phones, TV, cable modem, electric motors, etc.) and from outside I need to try to limit that interference while working on amps. Disregard for the moment, interference coming in through the AC mains. I also want to explore...

Hi.. I want to know how can we specify the data(electrical) passing through cable that we are designing in CST design studio to test the effect of EMI on the data passing?

This is not a homework.i am not able to understand rotating motional emf .so could u please tell why could we use the effective length to calculate emf in this case .

Hi, I am a Reliability Engineer. Currently, I am facing difficulties in finding the root cause to a defective EMI filter bead. Resistance measurements across the four leads (vertically, horizontally, diagonally) show that they are all shorted. However, a good ferrite bead should only be...

Hi all, I was wondering if a computer could be use to monitor the EMI on a house power line ? I have read a few papers on the subject, all of which proposing all sorts of devices, but I was wondering if it could be done directly by prompting a computer to monitor the electric flow through...

Question in relation to audio. I read online that a low impedance system is less susceptible to EMI and RFI than high impedance. How? I thought that high impedance = high resistance, therefore higher resistance to EMI and RFI. Would love to be updated with the explanation. Thanks.

Hello. We're in the age of the high speed computation. Personal computer clock speed is on the order of GHz and scientist looks for a way to raise the speed up to THz class. I've read this from newspaper and got some question. I've learned in class that radiation effect becomes severe as...

If we have a conducting loop, and a magnet (say North pole first) is pushed into it; that induces and emf and hence a current in the coil due to the changing magnetic flux, right? According to Lenz' law, the direction of the current is such that it opposes the change. So from the side the magnet...

Hello. Let's say there is a instrument needed to be EM wave-shielded in High voltage discharge lab. Building Faraday cage becomes necessary and the instrument is moved to inside the cage. The cage is grounded to lab ground and the frame ground of the instrument (it is also signal ground for the...

I hit a 1:40 ratio pulse transformer with a 1000V (100mA) sawtooth pulse and it creates a spark gap. Unfortunately it also creates a lot of EMI and my micro-controller and power supply has problems because of it. How do I stop this? How do I know what the wavelength is of the EMI field so I...

I have a 3 conductor wire that are all wrapped in a foil shield with wire conductor, for a total of 4 wires. I am connecting the 3 inside wires to audio left, right, and ground. This is an unbalanced setup, right? Where/how do I connect the shielding? Do I connect both sides (i think no)...

Hello all. I was wondering if there is a method or a device to check the quality of the twists on twisted pairs cable harness vis-a-vis EMI. i.e. someway (to tell is the twists are good enough to pass EMI testing). Cheers

how to purposely INDUCE EMI, noise, et cetera?? drill? phone? troubleshooting a GPU server, it has a card in it that generates a 20-100 MHz clock signal that goes to the actual GPU. Have worked on several of these units, when they fail the gpu doesn't get the clock signal so there is no VGA...

I have a temperature probe that I amplify with an OP amp and the circuit has to sit next to a video transmitter operating at 1280 MHz outputting ~ 800 mW of power. I can get the circuit about a meter from the transmitter if I absolutely have to but it is going to be in somewhat close...

A non conducting ring of mass m and radius R has a charge Q uniformly distributed over its circumference. This ring is placed on a rough horizontal surface such that the plane of the ring is parallel to the surface. A vertical magnetic field B=B0t2 τ is switched on. After 2 second from switching...

can i use surge protector for EMI protection inplace of EMI filter?what the difference between them?

Homework Statement The Attempt at a Solution Suppose that N pole of magnet is facing the solenoid considering view from magnet when the magnet moves close ... current is anticlockwise and increase from 0 to max till magnet reach starting of solenoid when it enters the solenoid ...

Homework Statement The Attempt at a Solution I think that both i1 and i2 will have same mag and direction and at same time the loop is not closed so will there be any current?

#1 No idea. #2 Please someone explain me the question. From what I have understood, I think it’s because on connecting wires, it will form a closed loop and will induce an opposing EMF which will induce current in circuit and which will provide an opposing torque to the motion. #3 Yes...

Homework Statement suppose there is a inductor connected to a battery and resistor in series ... i need to find the current in circuit at some time t i suppose i could use Kirchhoff's loop law but i don't know weather to take potential across inductor (L di/dt) as positive or negative. i...

Homework Statement A circuit has an inductor of self inductance 5L connected in series with a resistor of resistance R and a cell of emf E. After a long time, a new inductor of inductance 4L is suddenly connected in series to the arrangement, keeping the rest of the arrangement intact. What...

Are thermocouples not effected by EMI? I've been reading a lot of papers lately about temperature measurement. Most them involve temperature measurement in electrochemical devices such as batteries and fuel cells. Using micro-thermocouples seems to be common practice but this makes absolutely...

I would like to quantify the EMI on a circuit and I am confused on how to do that. I have two parallel wires that are laying on top of each other. I have tried to calculate the flux linkage and came up with: \Lambda = [l*\muo*I/(2pi)]*ln((d-a)/a) where a=radius of each wire...

(1)why is magnetic field generated when current is passed through a conductor? :confused: (2)why is current induced in a conductor by change in magnetic flux? :zzz:

Using Faraday's law for a closed loop we say that the EMI is -d(phi)/dt .Now this emf is induced in the closed loop...So between which two points is the PD equal to -d(phi)/dt Thanks

I have some chip emi filter capacitor type. Its parameters are size 0603 , 1000pF , tollerance +/-20%. I would like to replace it by filter of another vendor, with the difference of tollerance -20/+50%. As I'm understanding from attenuation characteristics chart, the replacement maybe even...

Hello everyone, Can anybody tell me that, actually what is the main function of EMI shielding gaskets?And i would also like to know the applications of EMI shielding gaskets. Best regards

Hi What kind of problems ESD can cause to a helicopter? Blades are usually made from a carbonfibre and they can cause electrostatic charge into a helicopter structure. Is there any method to prevent that to happen? If that charging occurs, what happens when heli is landing, will it discharge...