Flow of electric charge - typically movement of charge carriers, such as electrons. Measured in amperes (A).

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16 views

How to limit motor stall current?

I've run into a dilemma. I have two motors, both with a 2.2A stall current. I know that at start up, motors will draw their stall current because they are essentially stalled. However, my motor driver ...
0
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1answer
48 views

Current loop Converter

Is it possible to convert a 2 wires current loop to RS232, and from RS232 to current loop, I am trying to put an RS232 sniffer in the middle so I can see what they are communicating to each other. I ...
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0answers
29 views

Energy Monitor IC with built in Hall Sensor

I have looked at a couple of IC's which provide energy measurement(real power,apparent power), however these need to interfaced to a current transformer or a hall effect sensor since they cannot ...
2
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1answer
38 views

Options for higher current regulation in an aircraft strobe system

I've deployed a homemade strobe system using Cree 10W LEDs in my homebuilt aircraft. My implementation uses a simple PIC controller to do the flashing, an IRL2505 mosfet (driven by an NPN transistor) ...
0
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1answer
48 views

Multiple shunt resistor INA226

For a project I'm trying to build a measurement tool for USB where I can measure U, I and P using the INA226 from Texas Instruments. The shunt resistors all have a different value to measure a ...
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0answers
77 views

What exactly is Watts? [closed]

I am just confused as to what it is? I keep reading various explanation on the web and don't understand it. Could someone give me a detailed explanation and definition of Watts? thanks.
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2answers
65 views

Do I use a 5V 2A or 3A DC adapter to power my 2m (6.5ft) WS2801 LED strip?

(Please excuse me if my English is bad) I recently purchased a 5m LED strip, but I only need to power approximately 2m (6.5ft) of the 5050 RGB LED WS2801 strip, but I'm afraid that a DC power adapter ...
2
votes
2answers
229 views

What determines a load's current requirements?

Apologies if this question has been asked before. I'm sure it has but hard to find as wording of question may not bring up the duplicate question. Let us say we have a 10 ohm resistor as a load. ...
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2answers
34 views

Joining a raspberry Pi to an external hard disk cage power supply

I have an external SATA hard drive enclosure that has its own power input. I would like to be able to run a Raspberry Pi from the same power input. The enclosure takes a 12VDC input (currently I'm ...
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0answers
37 views

Odd MOSFET behaviour (in Multisim)

I have this circuit that's behaving in a strange manner. I am getting a surprisingly low current value flowing through the inductor when the path includes the N-channel MOSFET. Please could someone ...
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2answers
53 views

Are all solenoids waterproof?

I have an application where I need a solenoid to control a valve at the bottom of a tank. For unimportant reasons the valve needs to be inside the tank at the bottom. I was wondering are all ...
0
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1answer
78 views

Solar panel and 120mm Computer fan

Just before I start description my question, I would like to let you know that I am new at this. I am working on a solar air heater for one of my window. I've been researching and reading up on a lot ...
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0answers
72 views

current of inductor, a nice challenge

My professor calculate current of inductor in t=0^+. he calculated -1/30, but i reach to +1/30. anyone could help me? Note: (IL(0-))=0
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1answer
45 views

Calculate Current [closed]

how to i calculate current( Before Resistance ) from these parameters Voltage before Resistance Voltage after resistance Resistor Value Current After Resistance
5
votes
2answers
219 views

Transformer current peaks

So I am designing a power supply, got everything calculated, and decided to simulate it for a second to see if the smoothing caps keep the voltage above the regulator limit at max current draw. What I ...
0
votes
1answer
75 views

Series and parallel transformers?

I have two different transformers. The output of the first one is 15 volts and 1500 mA. The output of the second one is 5 volts and 500 mA. If I connected them in series (to get 20 volts) what will ...
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1answer
80 views

Relay that detects 240VAC and switches 12V DC

I'm wishing to detect the loss of AC power (in this case 240V) and when this event occurs have a 12V DC circuit go to earth. This will trigger an alarm for users to react to situation. Can anyone ...
0
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1answer
70 views

Graph of Second-Order Circuit

I know that a circuit is second-order circuit if there are two storage elements. I used pspice to simulate and I got this graph I feel like it is not correct. Please tell me my mistake. when there ...
1
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3answers
127 views

Sin signal from PWM

I wrote a program in order to use Pulse Width Modulation to simulate a sinusoidal signal. Added a low pass filter to get rid of the noise and the traces of it being a discrete signal. Added a half ...
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1answer
39 views

What is the current flowing through this switch?

I am looking at a circuit diagram like this: simulate this circuit – Schematic created using CircuitLab Switch 1 and switch 2 never are on at the same time (they alternate) I turn on S2 ...
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1answer
46 views

Calculating a voltage and power dissipated in a circuit after creating a supernode

I am looking at this circuit and I am trying to calculate Vx and power supplied by the 1A source. I believe my calculations for node V2 are correct but I am not too sure about my V1 and V3 supernode ...
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4answers
53 views

Voltage regulator (LM350) gives no current

I am trying to use a Fairchild LM350 to get 8 volt output. I am using basic circuit (page 5 of datasheet) to do that. I get the voltage I want but whenever I try to measure the current (by putting the ...
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2answers
67 views

Shape Memory Metal framed sail

I am working on a costume prop that utilizes a triangular cut sheet of emergency blanket spined with a single 12" long, .04" dia piece of nitinol wire that has a transistion temp of 115deg F. My plan ...
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3answers
186 views

How to calculate current going through an LED

I'm a beginner to electronics. I want to find out how to calculate the current in the following circuit. (I know how to calculate total resister value in serial and parallel resisters in order to ...
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1answer
211 views

Is there a good physical model for what happens when a light bulb suddenly goes out?

Sometimes a light bulb just stops working and goes dark for seemingly no reason. Can Dirac δ impulse to a light bulb serve as a mathematical model for what happens so we can assume that the electric ...
0
votes
1answer
28 views

Replacing an AC power supply that is 2 volts higher than the original but has the same current rating [duplicate]

I have an audio mixer that requires an AC 16 volt 1 amp external power adapter. I need to know if an 18 volt 1 amp AC external power adapter would work without damaging the audio mixer?
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4answers
118 views

Ohm's law clarification

I am slightly confused about Ohm's law. I understand V = IR, and I did a simple experiment on paper. The results are slightly confusing, so I was hoping someone could tell me if I'm right? First, I ...
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2answers
73 views

Can we measure a electricity? Embedded System? [closed]

Checking if electricity is passing through a wire or not using embedded systems. I want to check if power is there or not. I am new to embedded system. If yes how can I check.
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1answer
71 views

Current over CAT6 ethernet cable

How much current can a CAT6 cable reliably handle? I want to use 3 of the cores for +5V and 3 cores for GND. I'm wondering at what current I need to think of another power solution.
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0answers
59 views

Interface WCS2702 Hall-effect current sensor with Arduino

I am planning to use below current sensor WCS2702 (0~2A) rated measuring circuit. Since its sensitivity is very low. How to make detect by Arduino analog pin? Or how can I convert the low voltage to ...
1
vote
3answers
127 views

Simple Ohm's Law Question

Do I need a resistor if \$\frac{V}{I}=0\$? I am working on a simple circuit of an LED and a buzzer in series where the voltage drop would be 2 and 3 volts, so \$R=\frac{V}{I}=\frac{(5 - (3 + ...
2
votes
4answers
214 views

Current sensor measuring circuit

I am planning to design Rshunt basis current measuring. My current measuring range is 1A~2A. I need analog output of 0~5V analog with 1% accuracy. How can I do this? I found conversion circuit here. ...
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2answers
67 views

Emitter Follower Current Gain

I have two electronics textbooks and for some reason, both of them just gloss over configurations that are not "Common Emitter". Regarding the emitter follower, I understand that there's no voltage ...
-1
votes
1answer
72 views

Input 5V 100mA, output 200mA

I am new to electronics. I have come across a problem which I face. Will need some advice from here, as I am a student and would like to know: is there any way I can increase current in a circle. ...
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2answers
47 views

Unidirectional current and bi-directional voltage device

Which is that device which can take in current in one direction irrespective of the voltage polarity across it? ( We can rule solid state switches - diode, SCRs etc).
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1answer
69 views

How to draw constant current independent of voltage for capacitor testing

I have a 150 farad 2.7 volt super-capacitor. I want to test the cap under various loads, .1 amps, .5 amps, and 1 amp. I will be creating a graph of the voltage over time. How can I constantly draw ...
1
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3answers
75 views

Can't find the correct voltage and current source

I'm trying to self-study this problem but I got stuck. What I tried to do: The equivalent resistor R1 for the 12 and 4 ohm resistors is 3 (12x4/12+4). The equivalent resistor R2 for the 4 and 12 ...
0
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1answer
43 views

Max Current Output [duplicate]

Looking around at a couple of power supplies that I own such as a guitar pedal adapter that says it puts out 9V and 1700mA max, how does a power supply like this work so that it doesn't put out too ...
0
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2answers
64 views

For the circuit shown, use exponential model of diode to find value of R for which v=80mv

I know how to do this if the diodes were ideal, however here, they aren't. I've tried. Please help out. I've gone this far: log (iL/i1) = (v/vT) i2/i1 = e^3.345 (assuming vT = 25.4mv) i2/i1 = 23.31 ...
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votes
4answers
123 views

Can voltage be controlled in a fixed DC circuit?

If resistance is fixed in a DC circuit, can voltage still be controlled and changed from one value to another? Imagine this circuit, that has a fixed resistance of 1 Ohm, and the desired current is ...
4
votes
5answers
622 views

How does this constant current sink actually work?

So I have implemented a constant current source and it works wonderfully, but I was just hoping to try and understand it a little bit more! Here is the circuit in question: I have tried doing some ...
3
votes
1answer
76 views

Continuous current capacity of this conductor?

How much current can a copper conductor that is 2 meters long, 0.003m thick, and 0.00045m wide continuously carry? Also, the resistance is about 0.02 Ohms.
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0answers
30 views

Problem with DAC with current mirrors

I'm trying to design curent steering DAC with binary weighted inputs - I'm using M4, M5, M6, M7 to copy the reference current flowing in M8 with coefficients of 1,2,4,8. The idea is to put either 0 or ...
1
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1answer
146 views

Do these LED's have a constant current driver built in?

I bought these LED's of eBay and connected them all (5) in parallel with a 4.7Ohm series resistor each. This should have given me a total current draw of 1.7A. However, when I measured it, I was only ...
1
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0answers
46 views

at89c51 power supply [duplicate]

I am making a project using at89c51. I used my mobile charger (output: 5V, 1A) as the power supply. Will my IC get damaged due to the high current? I asked cause, without loading the program I ...
0
votes
0answers
36 views

How to calculate current boosting ratio in CMOS technology

In the following picture: The \$I_{out}/I_{in}\$ equals \$(1+C_2/C_1)\$. But I can't calculate it. \$I_{out} = g_{m}\cdot V_{GS}\$ for MOSFET \$\text{M}_2\$, but how to find out the voltage of ...
0
votes
1answer
42 views

Repairing (possible) earthing/ground issue in computer PSU? [closed]

I've got a computer that will no longer power on. It used to be willing to power on quite randomly, and ran fine when it did. I'm not an electronics savvy person, but i've done a manual check on the ...
0
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1answer
48 views

Cutoff and Conducting diodes

Why is D1 considered cutoff and D2 considered conducting ? Note : I am working with constant voltage model where the diode voltage is 0.7v and I need to figure out I and V. Please explain why D1 is ...
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2answers
83 views

How to choose a transistor for amplification

I've been trying to find information on choosing an NPN transistor but everything I've found seems to apply to saturated transistors only. I'm basically trying to amplify the current given from a 3mm ...
1
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1answer
35 views

Checking my understanding of “branch in parallel current” warning

A datasheet for a power connector I was looking at tonight has this warning: Note: Do not branch in parallel current which exceeds the rated current. If branched in parallel, current ...