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

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1answer
53 views

Fundamental questions about capacitors?

I have read several chapters in several textbooks, watched several in-depth tutorials, etc. There are still somethings that were either not explained clearly enough for me, or not explained at all. ...
0
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0answers
48 views

Fundamental questions about BJT transistors?

Take a standard NPN transistor. The doping of each element of the transistor is in the name. This is what is inside the transistor... The left "slice" of silicon is doped with an impurity which ...
0
votes
1answer
42 views

What is the difference between voltage UNBALANCE and voltage IMBALANCE?

I'm a Brazilian (so not a native English speaker) who just came across the user guide of a power quality analyser which has, among its features, measurement of both "voltage unbalance" as well as ...
9
votes
2answers
635 views

Why are some generic door alarm magnetic switches built using Normally Open reed switches instead of NC type?

Some generic, low-cost "door alarm" magnetic switch components are made of using "Normally Open (N/O)" type reed switches, ie, when the magnet is in proximity, the current stops flowing. If I were ...
0
votes
2answers
60 views

Voltage and Amperage in relays

i have a relayset for Arduino where i find these numbers on each relay: 10A-30VDC 10-28VDC Now, id like to connect that relayset with external devices that run 12V and all the way up to 35A. I was ...
3
votes
1answer
71 views

Is a device with high voltage and low current safer than a device with low voltage but high current should you accidently bump into the +/- pins?

For example, my lead acid car battery is rated at 12 V/700 A, whereas my switch mode power supply has 250 V/6.3 A. If I were to accidentally bump into the +/- pins of either battery (forming a full ...
0
votes
3answers
52 views

Newbie question: How do pots limit current?

From my understanding, a series circuit has a constant current, and when resistance is placed in the circuit it is voltage that changes across the resistors and not current. Potentiometers, from ...
0
votes
1answer
17 views

Acs712 current sensor ic interfacing with ade7858(energy metering ic)

I am trying to interface Acs712 current sensor IC with an energy metering Ic(Ade7858),there are two problems am currently facing. 1) The energy metering Ic takes in bipolar input (± 0.5 V) which is ...
3
votes
2answers
393 views

Are there downsides to using resistors with too high power ratings?

I'm hoping to measure the current draw to my ESP8266 with a scope and a shunt resistor. I think a 1ohm resistor might drop the voltage too much, so I'm thinking to use a 0.5ohm (or even a 0.1ohm) ...
0
votes
2answers
34 views

How to protect current sense IC from current transients

I'm planning to use a ACS712 current sense IC to sense motor-current in a project: http://www.allegromicro.com/~/Media/Files/Datasheets/ACS712-Datasheet.ashx The device I'm building uses a relay to ...
3
votes
2answers
41 views

Difference between Quiescent Current & Shutdown current?

What is the difference between Quiescent current & shut down current. I have searched a lot but didn't find valid answer. As per as my knowledge Quiescent current is the small current which flows ...
0
votes
1answer
26 views

Current/Voltage sensing for wheelchair battery using arduino

I am working on a project that requires me to monitor the power consumption of wheelchairs across a spectrum of different activities. (electric wheelchairs batteries are 2x12V) To do that I am going ...
0
votes
1answer
58 views

D.C power supplies, regulated linear power supply question

Design giving the necessary ratings and characteristics the necessary for the transformer, bridge rectifier capacitor and regulator , a 12v , 2A regulated power supply . the available mains supply is ...
0
votes
3answers
386 views

Light LED light?

I would like to mount 10 or 20 white LED on a thin rod, about 2 m long - and around 3 mm in diameter. I will need to accept various compromises for conflicting requirements, but I try to understand ...
0
votes
1answer
76 views

why my LEDs burned with the right driver?

I am trying to connect, in parallel, 18 LEDs that have these specs: LED size: 10mm; Voltage: 3.2V - 3.4V; Current: 20mA. Driver Type/Model: MeanWell LPC-20-350 (datasheet: ...
1
vote
4answers
101 views

12V solenoid drawing more current than it needs

I'm fairly new to practical electronics so I apologize if any of this is obvious. I am currently trying to use a microcontroller to control the energizing of several 12V solenoid valves using a PC ...
1
vote
2answers
78 views

Current Shunt Vs Current Clamp Meter - 15% difference Which one is right?

I have a variable AC power supply. 0-12V 0-1800A 60hz. I have always been told to trust the current shunts and not current clamps when measuring current. The current clamps are supposed to accurate ...
0
votes
0answers
35 views

Opacity/Transparency of Vacuum Tube Grid(s) to Electrons

The grids on a vacuum tube, biased or not, would block an electron that hits the wire mesh, and if biased, would attract and prevent additional electrons from passing through. It seems, that this is ...
0
votes
1answer
48 views

Zener diode minimum and maximum current

Why is the Iz max given before Iz min in this zener diode catalog? If you look at the list of diodes at the bottom, you can see that the maximum test current is given first. Is there something ...
0
votes
1answer
78 views

Current flow on Load (A)

simulate this circuit – Schematic created using CircuitLab From my analysis, and applying circuit theory, I find that Load(A) will have current flowing equal to 0.1Amps due to the PS, and ...
0
votes
2answers
109 views

9 Amps on Ethernet?

I already did my search but I found nothing to confirm it. I have a PCB and I want to connect a jumper that can carry up to 9 Amps. I tried a zero ohm resistance but it melted so I want to use an ...
2
votes
1answer
116 views

Current, Voltage, and Power Sensing for 115 V AC Circuits

I am trying to sense voltage, current, and power with an Arduino (Due) for monitoring and diagnostic applications. To get reasonably good input (better than Kill-A-Watt), I have designed an AC sensing ...
-1
votes
1answer
88 views

Is a current carrying wire always neutral? [closed]

Can we consider all current carrying wires to be neutral (assuming they have a negligible capacitance). Either way please can you explain.
0
votes
0answers
47 views

How does the current draw of a motor work?

I have a motor from an old drill and a 2.2 amp power supply. I want to connect the motor to this power supply, but I want to check if I have a good understanding of what will happen first. Assuming ...
0
votes
2answers
91 views

Voltage drop through a resistor using Ohm's Law?

I'm having a very hard time comprehending basic Ohm's Law. I was recently watching a video on the operation and use of Operational Amplifiers, and was completely lost because I couldn't understand ...
0
votes
1answer
111 views

How to find the direction of current of the circuit?

Okay this is the circuit The magnet given is moved up and down continuously at a high rate through the coil and generates a peak voltage of 4V. I eagerly use the right hand rule in order to find ...
0
votes
0answers
79 views

Transformerless Power Supply High Current

Is there any way for Transformerless Power Supply to output a High Current like 10A to 15A at 12V to 24V. I found highest of 500mA current output for Transformerless Capacitor Power Supply. I wanna ...
2
votes
1answer
31 views

How do I model an LED with SPICE WITHOUT access to a Manufacturer's Datasheet

Looking to create a model of an LED (RL5-WW15030 from Superbrightleds.com): ...
0
votes
1answer
31 views

Calculating charging current

I have following situation: Solarpanel with 20 W, 2 12V lead-acid batteries, the solar panel is charing the batteries. I measure the current coming from the panel with a ACS712 in a 3 minute ...
2
votes
4answers
566 views

Higher voltage or more amps?

Im planning on building a E-Bike and have made some calculations and only need my 190rpm/V brushless motor to spin around 600 rpm to give me a good speed. So by this calculation I only need to ...
0
votes
1answer
58 views

Charging Capacitor with Solar Panel

I have a 2.7V 100F super-capacitor. I am going to be charging it with a 6V 1W solar panel. Now the solar panel only puts out 6V when it is receiving the best sunlight so this means the output from the ...
1
vote
1answer
51 views

Can I Use Current Sensing Transformer Instead of Power Transformer

This is a follow-up on this question: How to Design Arduino Voltage and Current Sensing Shield Thanks to user bigjosh, I read the article: ...
0
votes
1answer
66 views

How to Design Arduino Voltage and Current Sensing Shield

I am trying to design an Arduino shield that measures raw voltage and current of a small refrigerator (115V, 60W). I have an Arduino Mega board. To one of the ADC inputs I have connected a (non-split) ...
0
votes
2answers
46 views

In a power supply, the current is a constant or gives whats the component/circuit need ? [duplicate]

I everybody, sorry for my english :D . i'm a begginer of electronic and i'm learning a lot of electronic component, voltages, current and so on. My question is about a charger (phone charger for ...
3
votes
7answers
601 views

Why does capacitor voltage lag current?

So far I've established the following: Current is the movement of charge over time, measured in coulombs/second. Charge is the electron in an atom. Voltage is the potential difference between two ...
1
vote
2answers
69 views

How will the current move?

I hope I've come to the right forum about this... I'm planning on building an e-bike using RC components, except I'm not going to use a transmitter and receiver. Instead, I'll use a Servo Tester to ...
-6
votes
0answers
41 views

pcb trace current limitations

i did try some calculators but some of them is complicated and i've got lost i've a width of about 2mm and depth of 1-3mm, how much current could they handle ? what if i feed them more current ...
0
votes
1answer
34 views

Help with basic inductor

I need some help with this basic inductor. If I have the current in that direction and those values of voltage and inductance, what is the value of $$\frac{di}{dt}$$ ? I know that: ...
-2
votes
2answers
62 views

Double the current capability of a mains socket by wiring another in parallel [closed]

I have an appliance that I know draws more or less 16A under 240VAC, but I only have 13A sockets around. Is there any off the shelf solution?
0
votes
0answers
40 views

How to measure current with a very small shunt?

I was wondering whats the best method to measure a current with a very small shunt? By small I mean like 5mOhms with currents going from 0,5 to 11 Amps. If you would use an op amp, which properties ...
0
votes
2answers
83 views

how to calculate power consumption

I have a Surface Pro 3 and am on the run a lot so I'm thinking about getting a deep cycle AGM battery to put inside my car so I have a constant power. I need to know and confirm some measurements ...
1
vote
1answer
53 views

Determining the duration that a battery can power a device

I am a little confused on how to determine the duration that a battery can power a device if you know the load's current requirements and the Amp-Hr rating of the battery... Also, how do you ...
0
votes
1answer
25 views

Are Bioimpedance sensor different from Biopotentials sensors?

I am building an portable health device , for which i am want ECG , GSR etc. then i came across 2 terms Bioimpedance and Biopotentials. Are these two same. Also can any one say the applications of ...
0
votes
1answer
60 views

Current regulator with controller?

I want to implement a circuit which allows to regulate the current flowing to the load. I have two use cases: Case 1 is the normal case where I would set the max. allowed current with a ...
0
votes
1answer
71 views

How much current can a computer power supply deliver when used as differential power supply?

I have a computer PSU which has +12 and -12 volt rails. Although on the side of the supply it says that the -12V line can only deliver 0.5 A, I have tried connecting the +12 and -12 lines across a 5 ...
4
votes
1answer
368 views

Why does current flow into the transistor in a current shunt monitor?

I'm looking at the basic operation of a current shunt monitor*, but I don't quite understand the 'operation' description given by it's manufacturer. Figure 1 shows the basic circuit diagram for ...
2
votes
1answer
124 views

How do I calculate the base and collector current in this circuit?

I have the following circuit, using a BJT NPN transistor: How can we calculate the current going into the base and collector? I was thinking of using Kirchoff's current law: \$I_1 = I_b + I_c\$ ...
2
votes
1answer
73 views

Maximum Amperage AA Battery

I have a simple question. How many amperes can an AA battery draw? I'm studying electronics and looking at the Ohms law: V=IR and taking as an example a 1.5V AA alkaline battery, and considering the ...
0
votes
1answer
78 views

Does electric potential influence the direction of current?

Main goal My main goal right now is trying to understand what negative voltage means, since I know AC can have a negative voltage and so can any electric component. I've pretty much read and seen ...
0
votes
1answer
36 views

Direction of resulting I through simple circuit with 2 voltage sources separated by 2 resistors in series?

I'm wondering how to find out which way the resultant current flows when you've got a really simple circuit with two voltage sources separated by 2 resistors in series. See the below circuit (the ...