Circuit Definition and 1000 Threads

A circuit breaker is an automatically operated electrical switch designed to protect an electrical circuit from damage caused by excess current from an overload or short circuit. Its basic function is to interrupt current flow after a fault is detected. Unlike a fuse, which operates once and then must be replaced, a circuit breaker can be reset (either manually or automatically) to resume normal operation.
Circuit breakers are made in varying sizes, from small devices that protect low-current circuits or individual household appliance, up to large switchgear designed to protect high voltage circuits feeding an entire city. The generic function of a circuit breaker, or fuse, as an automatic means of removing power from a faulty system is often abbreviated as OCPD (Over Current Protection Device).

View More On Wikipedia.org
Recent contents Top users
  1. S

    Maximum rate at which energy is stored in a LR circuit

    Homework Statement An Inductor L and a Resistance R are connected in series with a battery of emf E. Find the maximum rate at which the energy is stored in the magnetic field. Homework Equations Energy stored in an inductor : U= 1/2Li2 For a simple LR circuit with a DC voltage source the...
  2. A

    How can I relate the electric field to potential in a parallel plate capacitor?

    I want to calculate Electric field inside and outside a capacitor(two parallel conductor plates and in between a dielectric) which is fed by an AC voltage source. My problem is I do not know how can I relate the electric field to the potential in a capacitor. I got confused about the derivative...
  3. D

    Engineering Calculate the maximum power of the resistor in a circuit

    Homework Statement In an AC circuit of periodic current we know: ##E=6[V]##, ##R_g=50[Ω]##, ##L_g=\sqrt3 [nH]## and ##ω=50*10^9[s^{-1}]##. Calculate: a) All available power of the ##E## b) The resistance of ##R## so that the average power is max c) That average power from part b) Homework...
  4. B

    Orbital Shaker Rheostat circuit

    Hi all - I'm looking for a little bit of practical advice on an academic electronics project. I'm working on rehabbing an older laboratory orbital shaker for my lab, and I am working on identifying the issue with its problematic operation. This is the particular product...
  5. U

    Can anyone tell what's wrong with my circuit?

    I am doing basic tutorials with an arduino but I can't seem to get this circuit to work. I hooked everything up and ran the given code but nothing happens. The relay is supposed to trigger the led's on and off but when I run the code the relay isn't even making any noise
  6. L

    What is the current in these 3 circuits right after the switches are opened?

    Homework Statement What is the current through the resistor marked 'R' in all three circuits just after the switch is reopened after being closed for a long time? The Attempt at a Solution The explanation that we were given for (1) is that I = V/2R and (2) I = V/3R and (3) I = V/(R/2) but I...
  7. Pushoam

    Inductor as a battery in a circuit

    Homework Statement Can we consider an inductor as a battery of emf ξ = -## L \frac {dI } { dt} ##? For the above circuit, ##V_A - V_B = V_C -V_D \\ -L \frac {dI } { dt} = IR ## Here, the inductor is acting as a battery of emf ## -L \frac {dI } { dt} ##. For the above circuit, ##V_A - V_B...
  8. S

    Engineering How Do You Reduce Capacitor Values in a Circuit?

    < Mentor Note -- thread moved to HH from the technical forums, so no HH Template is shown > Hi All. Can someone give me some tips/tricks for reducing these capacitors? I understand that, when reduced, the value is 100uF but I don't get it... Thanks for your help.
  9. G

    Touch lamp circuit for posterity....

    As part of troubleshooting this circuit I drew a full schematic, only to find near the end that the blob chip was blown - the crack was hiding behind a capacitor. Anyway, since I went to the bother, I thought I'd post the schematic here in case it helps anyone else... I think the IC is a TT6061.
  10. G

    Engineering DC circuit analysis: conceptual mistake?

    Homework Statement Homework Equations[/B] I have a circuit that consists on 3 components in parallel: a current source Ia, a resistor R and a capacitor C. Ia is directed upwards, while the currents through the capacitor and the resistor are both directed downwards. Select the correct option in...
  11. G

    Optimizing EMG Circuit Design: Tips and Parameters for Improved Performance

    HAI EVERYONE i have designed a circuit for emg detection but its not working perfectly. may i know the parameters that to be considered in each stages and what should be the value of each parameters in each stages. (e.g. gain at IN stage =20). thank you..
  12. terryds

    Wye-Delta and Series-Parallel Circuit Problem

    Homework Statement Determine the equivalent resistance and the total current!Homework Equations Ohm's Law Wye-Delta Transformation The Attempt at a Solution [/B] I do the series on 10 ohm, 5 ohm, 3 ohm resistors, because it is node e-g,g-h,h-f, so it becomes 18 ohms (e-f). Then I do the...
  13. C

    RC Circuit: 20V AC Source, 12V Voltage Across R, What about C?

    A 50Hz AC source of 20V is connected across R and C. The voltage across R is 12V. The voltage across C is?
  14. S

    Solve RC Circuit Problem 1: V=IR, Q=CV

    1. 2. V=IR, Q=CV3. To calculate the current in the circuit in the case when the switch is open and steady state is reached, I assumed that no current will flow "across" the capacitors and so the current I will simply be emf/(r+R1+R2) = 12 V/(1+3+2) = 2 A. The voltage drop across r would be...
  15. L

    Navigate the Res-Monster Maze: Find R's Current

    Homework Statement Res-monster maze. In Fig. 27-21, all the resistors have a resistance of 4.0 and all the (ideal) batteries have an emf of 4.0 V. What is the current through resistor R? (If you can find the proper loop through this maze, you can answer the question with a few seconds of mental...
  16. L

    Capacitors charged in parallel

    Homework Statement Capacitors C1 = 6.97 uF and C2 = 1.54 uF are charged as a parallel combination across a 281 V battery. The capacitors are disconnected from the battery and from each other. They are then connected positive plate to negative plate and negative plate to positive plate. A)...
  17. C

    Purely Inductive Circuit -- Mathematical proof for current lag

    how we can mathematically prove that in a purely inductive circuit current lags behind voltage by a phase angle of π/2?
  18. S

    How do I calculate voltage drops and currents in a resistor circuit problem?

    Relevant equations: V=IR Attempt at solution: When the switches are open, R1, R2 and R3 are in series so the current in that case would be 12 V/ (2 ohms + 3 ohms + 3 ohms) = 1.5 A. When the switches are closed, the current across R3 is still 1.5 A, so the voltage drop across R3 is 1.5 A * 3...
  19. X

    Current flow in a two source circuit

    Hi guys, is the current flow in this picture correct? I'm trying to understand current flow in a two source circuit.
  20. E

    Can this circuit be solved? Please explain

    See the attached image. This circuit seems simple enough, but the fact that the voltage drop across each of the resistors is not the same means that equivalent resistance methods cannot be applied. Is more information required? Thanks for your help!
  21. E

    How to know if a certain number is a don't care in KMAP

    Homework Statement given the function $F(a,b,c,d)=Σ(0,1,2,4,5,10,12)$ how can i know for sure if 8 is a don't care? and is it possible for 6 and 14 to be don't cares? Homework Equations it's part of a bigger exercise, so the boolean expression i got from previous parts is a'c'+c'd'+b'd' The...
  22. R

    Calculate the RMS current of an ac circuit

    Homework Statement : [/B] calculate rms value of current i= 3+ 4 sin(ωt+π/3)Homework Equations : [/B] Irms2=(∫0T [I(t)]2dt)/TThe Attempt at a Solution: I tried to integrate but I'm getting a T term.
  23. Harshna

    Engineering Find Currents I1 and I2 in an Electric Circuit

    Homework Statement I need to find the currents I1 and I2 in the attached image, but am having some difficulties grasping the concepts. I am given E(t) = 338sin(t) as well as values for R, L and C. I think I know what I need to use but I am not sure how to put it all together Homework Equations...
  24. marsupial

    Valid and Invalid interconnections

    Homework Statement My question is about the following circuit: https://ibb.co/hWnb9v According to the answer, it is an invalid circuit as the voltage drop on the left totals 14V and on the right totals 16V, and they have to be the same between any two terminals. I understand that it has to be...
  25. ryanuser

    Can a simple metal detector be modified to detect pipes at a higher voltage?

    Hello, I am a civil engineering student undertaking a project to investigate the effect of pipes and pipelines beneath the ground on the urban city environment above. In order to proceed I am designating a simple metal detector. Due to low depth capability of all commercial metal detectors mine...
  26. G

    Engineering Voltages and current in a circuit: incorrect signal?

    Homework Statement Consider the circuit in the figure and calculate V1, V2 and IA. Notice that the symbols V and A represent, respectively, an ideal voltmeter and an ideal ammeter. Homework Equations Ohm's Law $$V=RI$$ KVL The sum of the voltages of a mesh in a circuit equals zero. We...
  27. T

    Circuit breaker using microcontroller project

    So I am trying to make a circuit breaker using a microcontroller. I managed to get as far as this So I have the CT with a peak detector running to the adc. I then calculate the rms by dividing by root 2, which I then compare with a reference in this case 10A and it trips via the mosfet/relay...
  28. M

    Need help with a mod-6 counter using JK flip flops w/ control bit

    Homework Statement [/B] I am currently working on an assignment in which I create a six-state up/down counter. The purpose is to understand the functionality of flip-flops within a circuit among other things. There are 3 input bits (Q2,Q1, Q0), and a 4th control bit (C) which determines the...
  29. C

    Potentiometer Circuit 1: Balancing the Current - Solving for Ix and Rx

    1. problem statement, all variables and given/known data 1) What is the relationship between Ix and Rx ? 2) Prove that on varying resistance Rx , Ix reduces to zero . Homework EquationsThe Attempt at a Solution Assume resistance of Galvanometer is ##r## . Total resistance in middle branch...
  30. S

    D-Flip-Flop Circuit: Understanding the Enable and Clock Input Functions

    So I have been watching his videos trying to get ready for second year engineering (electrical). However, I am very confused as to what exactly is going on when he is pressing the enable/pulse switch during the run-through at 14:45. He has the enable connected to a capacitor, and he calculates...
  31. J

    Find the value of resistance in the circuit

    Homework Statement Homework EquationsThe Attempt at a Solution [/B] I don't understand how can current in ammeter be zero .Why is 2V battery not sending current in the right loop ?
  32. C

    Calculating Currents & Voltages of an RLC Circuit

    Homework Statement An RLC circuit contains the following components in series: a 15Ω resistor, a 200μF capacitor, and a 12mH inductor. What are the currents and voltages through each component? It's known that the current through the resistor is 1.75A⋅cos(250πt) Homework Equations χL=ω*L...
  33. C

    Resistor and current in a circuit

    Hello , I have to teach a group of 9th grade students role of resistor in a circuit and how it affects the current in the circuit . This will be their first exposition to circuits .So I need a good and simple analogy so that students can grasp these concepts easily . This is what I plan to...
  34. prakhargupta3301

    Why isn't the Heat generated = Voltage*Charge carried?

    I found out that Power of an electrical circuit will be equal to the work done divided by the time T for which the power by the cell or battery is exerting to keep a potential difference V in the circuit for a charge Q. Hence, Power= Voltage*Charge/time Which then can be written as: Power=...
  35. B

    How Does Gauss' Law Apply to Currents in Electric Fields and Circuitry?

    I am designing a device, which will utilize an electric field. The question I have run into is whether or not the current is treated as the charge enclosed for Gauss' Law, or if there's another way I would calculate it. Also, am I correct that the voltage of the circuit would be different than...
  36. esha

    Potentiometer nulling voltages in a circuit

    this is the potentiometer and the emf of cell E2 is unknown. now to know the emf just finding the null point of the galvanometer is enough. its because at that given length the potentiometer has the same potential as the cell. but why are they equal at null point? Sent from my Micromax E311...
  37. S

    Short Circuit Current on 161kv line

    I work at a electric arc furnace. We measure a lot of items on our furnace and found that some weeks we preform well and other we do not (kwh/ton). With everything else being equal i believe that the utility's available short circuit current is affecting this. The utility feeds our substation...
  38. F

    RC circuit -- finding the charge on each capacitor

    Homework Statement I have to find the charge ##q## on the capacitors (all have capacity ##C= 4 \mu F##) and ##\mathscr{E} = 12 V##, ##R=50 \Omega##Homework EquationsThe Attempt at a Solution I wrote the nodes current equations ##\begin{cases} i_{1}+i_{2}=i_{3}\\ i_{3}=i_{4}+i_{5}+i_{6}\\ ...
  39. R

    Maxwell Ansoft and Circuit Editor

    Hi Guys, I'm simulating a SRM in Maxwell 2D transient solution and my wingdings are external but a group of them are not able to show in the maxwell circuit editor. I've got this error: Cannot find the matching inductor in the imported file. Can someone help me with this?
  40. S

    Electricity (charge on capacitor in circuit)

    Homework Statement A capacitor of is connected as shown in the circuit. The internal resistance of the battery is Amount of charge on capacitor plates will be : Homework Equations no relevant euqations given. The Attempt at a Solution I don't even know how to begin with the question:(...
  41. S

    Electricity (Potential difference between points in circuit)

    Homework Statement In the circuit shown, what is the potential difference VPQ? Homework Equations No relevant equations given in question The Attempt at a Solution Tried kirchhoffs law. Tried to find equivalent battery and resistance but that doesn't seem to be possible.
  42. A

    A circuit board to charge a LiPo battery?

    Hi guys I'm creating a prop that's probably going to have a 7,4V 5000 mah 45C RC Lipo battery in it, and I'm planning to keep it permanent in the prop with a charge circut to charge it up with usb perhaps. I've thought of using a tp4056 circuit I have laying around and it seems like the...
  43. evinda

    MHB All boolean functions are computed by a depth 2 circuit

    Hello! (Wave) I am looking at the following exercise (pg. 92, ex. 11.1 , book:Gems of Theoretical Computer Science by Uwe Schöning ) : Why can all boolean functions on $n$ variables be computed by a circuit with only 2 levels (a depth 2 circuit) ? What is the size ( number of gates ) of such a...
  44. R

    Calculating Heat Loss in a Series Circuit

    Homework Statement Determine the heat loss in the circuit that is connected in series with two batteries (12 V and 6V) and two resistors (6ohms and 4 ohms). Homework EquationsThe Attempt at a Solution I used the difference in P = V^2/R, the power dissipated in the circuit, to calculate the...
  45. F

    Complex Capacitor Circuit (for me)

    Homework Statement 1. V for C1 2. Let's Say "C" is Resistor then C1 = R1 etc. how to get Eq Resistance for this Circuit ?[/B]Homework Equations Faraday's Law, Kirchoff Law The Attempt at a Solution [/B] for no 1 :I just want to make sure. point A is transfering negative charge to C2 and...
  46. e0ne199

    Engineering Problem with series RLC circuit and dependent source

    Homework Statement here is my problem : Homework Equations like usual, the problem is related with RLC circuits and transients The Attempt at a Solution [/B] from here, the solution is obviously wrong because from the solution, its alpha should be -300 and not -0.4...and from the...
  47. evinda

    MHB Why isn't the circuit a combinatorial one?

    Hello! (Wave) I read the following about parity functions: Since I haven't heard of combinatorial circuits before, I have searched for them. I have found the following: http://http://www.math.northwestern.edu/~mlerma/courses/cs310-04w/notes/dm-combcirc.pdf I haven't understood how we deduce...
  48. H

    How to choose a fan for open circuit wind tunnel?

    Hi all, I am trying to design a open circuit wind tunnel, and I've got to the point where a fan should be selected. However, I am not familiar with fans at all, so I am wondering if you could help me! My understanding is that the fan selection process is quite similar to the pump selection...
  49. gimak

    Impedances in a 5 element circuit

    Homework Statement Just help me with 18 b. Homework Equations V1 = c1I1Z1. Same for V2,3,45. V = V1+V2+V3+V4+V5. V/I=Z=impedance. The Attempt at a Solution Maybe because of symmetry Z1=Z2 & Z3=Z4. Perhaps Z5 takes out one of the branches? Can I get a hint?
  50. P

    Logisim question -- Simulation of a small logic circuit is not working

    I am trying to implement the following circuit in Logisim, yet all I get is y=0. Any idea what might be the problem? First image is what I am trying to implement; second it my Logisim attempt which yields 0. I'd appreciate some feedback.
Back
Top