Questions tagged [electrical]
The electrical tag has no usage guidance.
302
questions
0
votes
1answer
34 views
Soldering back the disconnected wires from the charger board [closed]
The attached link images are the front and back photo of the board inside my charger. This charger is used to charger my son's toy car. Unfortunately, the wire soldered on this chip got disconnected. ...
3
votes
5answers
180 views
If ground and neutral are bonded at main panel, why aren't all grounded device chassis energized?
I know this is a question with variants that have been asked countless times on the internet and on this site. Believe me that I have scoured through these questions and answers in search for a ...
1
vote
3answers
138 views
How to figure out what resistors are in the E12 and E24 series?
Is there a way, other then remembering, to figure out what resistors are in both of these series?
8
votes
2answers
233 views
Phasing Order in IEC Color Codes
Currently, IEC 60445 international standard is used for conductor terminal color identifications. I've obtained different versions of the standard (2017 being the latest) and also IEC 60446, which was ...
0
votes
1answer
71 views
Impedance load matching
So I've done this so far, and know one of the components is a 50ohm resistor. However I dont know where to go from here. How do i decide if its an inductor or a capacitor?
This is a past paper exam ...
1
vote
0answers
41 views
Maximum power transfer theorem [duplicate]
Im very stuck on where to go with this question.
The examples in class used complex numbers, where as this doesn't seem to need them.
Im aware that Zs = Zl, but does Zl=Cl+Rl?
Any help with how to ...
0
votes
1answer
65 views
Styrofoam cooler/chest ok for electronics project?
I'm building a DIY power supply using 6 server power supplies. I've been looking for a case/enclosure to hold them and the necessary wiring and came across a styrofoam cooler that's the perfect size ...
2
votes
2answers
92 views
How current is steady after pinch off voltage?
I was studying the JFET. In the books and other material it is mentioned that when the voltage between the drain and source is increased then drain current is also increased. After a certain point (...
0
votes
1answer
83 views
Maximum safe working voltage of capacitors
The answer is 30kV.
My method led to an answer of 41KV, where did I go wrong?
I believe I cant just add the Vmax(s) at the end, but what would I do instead and why?
0
votes
0answers
58 views
Help with determining the open circuit voltage
Can someone go through why Vxy= -84mV?
Given the values off VB=180mv
R1=22ohms
R2=68ohms
R3=150 ohms.
Many thanks
0
votes
1answer
74 views
Compensated vs uncompensated Op Amps [closed]
What are the advantages/disadvantages of compensated and uncompensated op amps?
Thank you in advance.
1
vote
1answer
115 views
can someone help with this question with capacitors
Please I need help solving this one, the book is Thomas Floyd 3rd edition Electric circuit fundamentals.
The final answer is supposed to be \$ \text{0.0052 } \mu F\$
The ac source frequency \$f=...
0
votes
0answers
70 views
Relation between torque angle and power factor
What is the relationship between torque angle and power factor for a induction motor? Here is my understanding.
Lets say a stator coil produces a magnetic field and the field induces voltage in a ...
0
votes
2answers
53 views
How VFD affects an isolated IOT system
To avoid noise from the external system I tried to isolate the internal completely. So I added DC-DC isolated converter with signal isolation. I have attached the picture. Still when reading data and ...
0
votes
2answers
136 views
Best way to power 120 VAC fog machine with DC?
OLD: I have a 120 VAC 400 W fog machine. I want to mount this on a robot that can supply 12 volts. Can I just reuse a $10 car inverter from Amazon or is there a better way to do this?
UPDATE: So I ...
0
votes
0answers
42 views
Robotic tool changer functionality
Have you any idea how is a changeable end-of-arm tool powered when is interfaced with an ATI tool changer or something similar ? My first thought is that on both sides of parts is a F/M connectors ...
9
votes
2answers
2k views
What property of a BJT transistor makes it an amplifier?
I know how we can amplify a given signal using BJT transistors by biasing them. But I would like to know what is that crux property which enables BJT transistor to act like an amplifier. Is it the ...
-3
votes
1answer
43 views
what is the difference between active and reactive power?
What is active and reactive power ?
does the active power means power flows from source to load and reactive power as its vice-versa?
-1
votes
0answers
75 views
clamping the battery voltage with zener diode?
I want to do an experiment with a battery I have. I have 200AH 6v lead acid battery and I want to charge it with maximum current the battery can take in bulk stage, then in float or acp. stages, I ...
0
votes
0answers
12 views
TC-ER cable type for U/G installation
Can I use TC-ER type cable for Underground installation.
Underground installation is in PVC conduits (schedule 40). PVC conduits are protected using lean concrete (sort of duct bank)
0
votes
3answers
149 views
Using Thevenin's theorem, how do you find the Thevenin voltage?
The above image shows a circuit. It is required that we simplify the circuit using Thevenin's theorem to find the Thevenin voltage, current and resistance.
I've done a countless number of problems ...
0
votes
1answer
58 views
Capacitor question - energy from pushing a baby stroller
I’m making a circuit that will be added to a stroller. With a 24 volt DC motor, I’m trying to power the capacitor by walking around & simulating a baby/mother experience and if I run into a hill ...
1
vote
2answers
71 views
Use PNP sensor on NPN input
I want to use the IPOS3602 datasheet iPOS3602 this is a small motion controller. I have another datasheet which is protected so I can't share it. This datasheet states: The inputs are compatible with ...
0
votes
0answers
63 views
Make Input and Output circuit really I/O
I currently have a self designed I/O board. I'm using the LPC1768FBD100 Microcontroller NXP 3V3 and created 20 inputs and 14 outputs. My design allows only inputs to be inputs and outputs to be ...
0
votes
1answer
50 views
Sensor with integrated ID
I'm looking for another solution to a problem.
I have 4 of the same infrared sensors which detect if an object is close or not (pretty simple). The difficult part now is that they don't have an ...
4
votes
1answer
610 views
Would the motor reverse if phases swapped for this case?
A servomotor power connection pins are given as follows:
U V W are the three phase terminals. Would the motor reverse if I mistakenly swap phases U and V namely if I connect pin 1 to W and pin 3 to U?...
0
votes
1answer
86 views
How to know how much current is generated?
My input voltage is 4.5V. Based on this datasheet here, where do I reference in the datasheet to obtain the respective desired output current?
Some background info:
This is the schematic diagram of ...
5
votes
2answers
724 views
Bulding a physical calculator from scratch [duplicate]
As you can probably tell I am relatively new to the electronics scene and I'm rather stuck on a project I'm doing for school.
I am on my second year of an Electrical engineering degree, tasked to do ...
1
vote
3answers
34 views
Connecting the Block AIM 5.0/2.0 auto-transformer to UK three-wire plug
I am not electrically very knowledgeable person. At the moment I am trying to connect a Block AIM 5.0/2.5 Auto-transformer to a piece of very sensitive medical equipment. The auto-transformer was ...
1
vote
1answer
81 views
How do I connect an LED with floating DC voltage?
I want to connected an LED at the output of 500V DC. This DC power supply is made by 3phase DC rectifier and is floating.
I would like to have a display on the front panel of the supply which will ...
1
vote
1answer
49 views
Problem with Network Topology based on circuits
I have started reading a book lately which covers an introduction to electric circuits. Currently, I'm trying to learn the basic network topology needed to solve exercises in a more efficient manner. ...
0
votes
1answer
54 views
LED lights with a dim light in open circuit [duplicate]
I was installing new LED lamps on my kitchen, which seemed to be functioning well. After turning off the lights, the newly installed lamps still had a dim light, that kept itself for quite long.
I've ...
0
votes
0answers
43 views
Find force pull solenoid
Sorry for the previous post that was wrong.
I want to knowF=(NI)^2*μ0*A/2L^2
A What is the cross-sectional area?
NewRef.https://www.researchgate.net/publication/...
1
vote
1answer
96 views
Bjt circuits, “Vbe = 0.7 at edge of conduction”
could you explain what "eoc" and" eos" (edge of conduction and edge of saturation) is?
The problem says "Vbe = 0.7 at edge of conduction" , is that in cutoff mode?
-1
votes
3answers
95 views
How is e=200sin(𝜔t+40)V equal to E=200∠40?
If we expand the first equation it goes like this: \$e = 200(\sin(\omega t)\cdot \cos(40) + \cos(\omega t)\cdot\sin(40))\$,
Which means there is still \$\sin(\omega t) + \cos(\omega t)\$ remaining in ...
-4
votes
1answer
123 views
Earthing system on a mobile vehicle?
We have an electrical system which needs a low impedance earthing system below two ohms. We have provided a proper earthing system
in our factory and it works well. Now my question is if the system is ...
0
votes
1answer
54 views
Burn In component testing
For pre and post electrical testing of burn in components under test: what is the best way to measure current and voltage through said burn in components before and after burn in to verify if the ...
0
votes
1answer
64 views
Does the depth that you plug in an appliance have an effect?
Let us assume that we have an outlet that is a bit into the wall(receptacle is set behind cover, so difficult to plug in larger plugs). If an appliance - lets us say a phone charger - were plugged in ...
0
votes
1answer
299 views
Help Me simplify: C*(A+B) + ~A*B
I know the answer is AC + ~AB, but how?
I have tried:
B(~A+C) + AC and stop.
Also, I have tried:
...
0
votes
1answer
16 views
Two port network z parameter determination
I would like to know how it is solved in book as I found that it is way quicker than the way I solved. Any detailed explanation will be appreciated.
0
votes
1answer
37 views
The differential protection relay
The differential protection relay may lose its stability through fault due to the saturation of a CT magnetic circuit during a short circuit condition. To overcome this, which type of relay should be ...
-5
votes
1answer
37 views
What is the current drawn by a faulty appliance? [closed]
Is the current drawn by a faulty appliance greater than the rated value or is zero?
0
votes
3answers
116 views
What are these connectors called (home applicances)?
I see these connectors inside a microwave oven and other home appliances. They are installed on the ends of wires and have round edges, while the middle section is flat. What are they called and do ...
0
votes
0answers
19 views
why the stator magnetomotive force lags behind stator armature current in salient pole alternator
https://circuitglobe.com/two-reaction-theory-salient-pole-synchronous-machine.html?fbclid=IwAR1ODRDONC27LIL83Lvb3WohPaSrIG4BRZ8l-ATyeloZEqrZ6juKw__jNMQ]
Hello guys in two reaction theory of salient ...
1
vote
3answers
237 views
Help identify positive, negative and ground on a LCD screen PCB
Let's just say I know nothing about electronics, so please bare with me on improper terminology.
I have a LCD screen that I have disassembled as I am trying to make a Touch screen mirror fit into a ...
0
votes
0answers
72 views
Arc Flash carbonized particles initiation
Ok. I'm investigating an arc flash accident.
In the above image. The breakers encountered a first short which deposited carbon into the plastic enclosure and lugs. During a second event. The ...
10
votes
2answers
3k views
Why does the current not skip resistors R3 and R5 when R6 and R4 have no resistance?
I do not understand why the current still flows through resistors R3 and R5 when R6 and R4's resistance is 0. To me, it would seem that the current would skip R3 and R5, however the answer key says ...
0
votes
1answer
39 views
Corona and conductor
We are decreasing corona by increasing conductor size and making it hollow but according to definition corona depends on level of voltage so eventhough you make it hollow and increase conductor size ...
0
votes
2answers
161 views
High voltage drop when load is connected [closed]
I'm getting 6 volts open circuit voltage. Whenever I connect a load (resistors), there is a huge drop in voltage values. Does it signify power input is less or is there any other reason for the same?
...
0
votes
1answer
66 views
Assemble Peltier Cooler to Li-poly Rc Battery
I have procured a thermoelectric cooler (TEC, this one) and my purpose of the TEC is to produce current for the Li-poly RC battery to increase its battery life. The Li-poly RC battery has 7.4V stated ...
