/r/ElectricalEngineering

Photograph via snooOG

A place to ask questions, discuss topics and share projects related to Electrical Engineering.

A place to ask questions, discuss topics and share projects related to Electrical Engineering.

Rules

1.Be Respectful

Be respectful of others opinions. Intelligently explain why they are wrong, don't just say they're an "idiot".

2.No Advertising

No advertising of products, services or personal websites/blogs. Some exceptions can me made for personal websites and blogs for things such as scholarly research papers and reports.

3.Limit the Memes

A sprinkle of funny posts help keep the sub from becoming stale. However, if we see off topic, an influx and/or multiple posts (more than one a day) from a single user, they will be removed at the moderators discretion.

4.We won't do your homework

We will not do your homework for you. If you'd like help with an assignment, feel free to post the question along with your progress so far and specific questions that you have. Generic "Please solve this problem" posts will be removed.

5.No Consumer Product Tech Support Questions

No tech support questions on consumer products, unless it is truly an engineering problem. /r/gadgets is a better place for non-engineering problems.

6.No Building Electrical Posts

Posts about building electrical (residential or industrial) as well as electrical grid systems should be taken to /r/electricians.

7.No General Education Posts

Posts related to education that are not specifically EE should be taken to /r/EngineeringStudents.


If you find a post violating one of these rules please report it so the mods can review it ASAP.

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/r/ElectricalEngineering

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1

Question for the Test Engineers

So I am a test engineer that does electrical and environmental testing for our products. I’m fairly new to this but I can see that our process isn’t the most efficient. I’ll give a quick rundown of our current process and then I want to ask you guys how you do it or what software you use.

So we have customers within our company that will request certain tests be done on certain products. We have around 24 different tests that they can ask for. We use ALM, or Application Lifecycle Management to receive requests and add comments. Test plans are uploaded straight to there but that’s about it. The application itself doesn’t track what tests are needed, progress on which tests have been completed or failed and when. It’s basically just a place for us to upload the test plans and make comments to the customer. For each test if we need more info we go into the specific test plan and read it there. This is okay when we don’t have a lot of projects but when we do it gets really messy and hard to keep track of everything. For example some tests can done on different projects simultaneously if those projects all have similar parameters but in order to check if they align we have to go into each test plan manually and look or make our own table.

There has to be a better way right? Something where can track which individual tests are needed for each test in every project. Ideally it would be something our customers can use to submit requests where they select which tests are needed, provide the needed info for each test, and also something for us to select when a test if completed so they can see progress. It’s also important that we can make comments and keep track of all communication and go back to old projects that have been completed. Looking into ALM it seems like something for software developers to keep track of bugs and progress on releasing a new application so I am not sure why that is what we are using and the main client.

I would be really interested to hear what you guys do in your experience and how you keep track of things. Maybe this is just the way it’s done and I need to get used to it. Maybe there’s something better out there. Thanks for reading this!

0 Comments
2024/12/02
19:27 UTC

1

Math Related Question

The problem: B = 200mT. If we consider a square surface with an edge length of 10cm. How large is the magnetic flux?

Solution: 0.2T x 0.1cm x 0.1cm = 2mWb

Reading a book and there's this problem in it. I have both the problem and the solution but I don't understand why or how it was solved.

0 Comments
2024/12/02
19:23 UTC

3

Mesh analysis

Hey guys from my understanding, the current in mesh 1 is simply 3A, and power of that 5ohm resistor is I^2R (3^2 x 5) which is 40W, however im curious, wouldnt the other voltage and current source affect that branch as well?

0 Comments
2024/12/02
19:10 UTC

1

Digital Logics

Can anybody give me some idea on how I can design a logic circuit which has both full adder and full substractor(in a single circuit) using a mode switch?

0 Comments
2024/12/02
18:34 UTC

1

How do I model a saturable reactor in matlab/simulink?

Hello!

I need for an application to model a saturable reactor, which can change the reactance based on the control current that I provide from a 3 phase controlled thyristor rectifier. I already did the rectifier bridge, I just need an idea of how to implement a variable reactance based on the B-H hysteresis loop.

I was thinking that maybe I can export the data for the DC voltage and DC current from the rectifier output in simulink and get it into matlab so I can implement the equations that describe the Saturable reactor in matlab, but then I need the values of the reactance back in simulink...

Any ideas of how to do it?

1 Comment
2024/12/02
18:21 UTC

1

Help in Learning Substation Design by self

Hello everyone, I would like to learn about substation design myself as I have almost 2 to 3 month of freetime and I am looking for starting point.

How should I approach this task? Are their any books that deals with the design or I should look into standards and guidelines like the ones by IEC or IEEE?

In addition to that, what are the areas I must focus while designing or learning like earthing, fault analysis, etc?

Any or all help will be appreciated!!

0 Comments
2024/12/02
17:08 UTC

2

HELP!!

Im working on some landing gear for a drone and I need to figure out a way to make the legs (which work by having a push button adjustment that stays down until all 6 legs touch the ground, in that moment the "spring" will release and the button will pop out locking all the legs into place) work. I am unsure how I would be able to keep the button down and have the drone sense when it touches the ground. If any of you guys have a simple solution or any advice please let me know!

10 Comments
2024/12/02
16:10 UTC

0 Comments
2024/12/02
14:56 UTC

21

Fire Alarm on a Circuit Board

Hello! We have this school project about making a Fire Alarm on a circuit board.

Materials are: Circuit Board Thermistor Potentiometer 10 Kilo Ohm Resistor Buzzer Lm358 Connecting Wires Battery Battery Holder

I've made a layout on the board but I've tried it and it doesn't work. I really am having trouble with it. Our strand isn't really related to engineering of any kind so that's why I'm a bit clueless. I'd appreciate if someone helped me out with this. :)

4 Comments
2024/12/02
14:16 UTC

0

Can you help me calculate the equivalent resistance between A and B?

8 Comments
2024/12/02
13:02 UTC

3

AC frequency for hypothetical new from scratch power grid?

The world power grids right now operate in either 50 or 60Hz AC frequency. If we where to design a new power grid in a hypothetical situation knowing all of the tradeoffs we know now what would be the best frequency for such a power grid assuming we can start entirely from scratch? Let's focus our discussion on large power grids handling gigawatts of power in nation/County wide industrial loads.

Some basic pros and cons for higher vs lower frequencies:

Smaller transformer sizes for higher frequency in same power handling capacity.

More use of stranded wires due to skin effect in higher frequency.

Simple synchronous AC motors RPM are tied to grid AC frequency. Assume all equipment using motors will be designed to run at the new selected frequency.

Much more fine details I can't list right now but please add in comments. From what I can see it seems a higher frequency than what we have now is definitely a better option.

17 Comments
2024/12/02
12:54 UTC

3

Bicycle Generator Working-

Regarding: https://www.reddit.com/r/ElectricalEngineering/s/JwCwXO2WrB

I tried Bicycle Generator using the following circuit, 12V 6W Dynamo (available as a kit at amazon), 4 diode full wave rectifier, 10 microF capacitor x2, 5V LM7508 Regulator, Outputs constant 5.01V and 0.5A current.

I worked out this far using multimeter. Help me with the following questions-

Can I charge a mobile with standard rating 5V 1-2A current? Will it show atleast charging icon (college first year project)? How can I connect the two wires to charge a mobile? Should I use some kind of usb output module? (If there's other way, please mention)

3 Comments
2024/12/02
12:27 UTC

1

How can I insert a 199 gate circuit into logism?

Without logism crashing

0 Comments
2024/12/02
11:33 UTC

3

Best book for fundamental

Hello everyone, I'm planning to switch to electrical engineering and trying to grasp the fundamental principles & concepts of engineering along with interdisciplinary fields, can you please recommend a book that helped you study & understand the fundamentals of EE & some good resources to learn ( appreciate if it's project based learning that's how I learn the best) 🙏

1 Comment
2024/12/02
11:26 UTC

1

Does someone have any idea

4 Comments
2024/12/02
11:20 UTC

1

Simulink

What’s your opinion on Matlab/Simulink software for circuit simulation ? Is it better than LT Spice ?

5 Comments
2024/12/02
10:53 UTC

1

UPS goes into bypass , 4 fans not spinning.

Hey everyone. I am faced with an issue with this SPS (name) UPS of an hotel that supports an elevator during power cuts. It seems to go on bypass because it reaches a high temperature due to the fans not spinning. Id think its a rare case for all the fans to be out of work. The message displayed showed me this. It meant that work was terminated being that the device cant maintain a healthy temp. So im gonna try and give each fan power from a small 7.2Ah 12V battery to see whether any fans have issues but other than that could it be something in the electronic board. Have any of you been faced with this before ?

0 Comments
2024/12/02
10:15 UTC

1

How to make the best out of my college course?

Hellooooo I’m doing EEE in some college in India .Now I EEE and EEE isn’t the same but engineering is engineering . For weeks I’ve heard people saying to drop the course or stuff like it’s the hardest course in all of engineeering.And frankly I don’t care much for it My question is how do I make the most of everything electrical ,how can I truly take my learning experience to the next level .How can I make it fun?

2 Comments
2024/12/02
10:12 UTC

1

What is this schematic symbol?

2 Comments
2024/12/02
08:15 UTC

1

Device was dead for weeks, now works all of a sudden - why? How to prevent this from happening again.

Hey there, Don't know if this is the right place - but I need some technical / electrical advice.

Have a Phillips smart mirror in my bathroom. Some weeks ago a friend used the light switch and turned off the always on smart led mirror. Didn't turn on again after that.

Wanted to replace the power supply.. But yesterday it suddenly turned on out of nowhere and works flawlessly again.

So where is the source of the problem? Cold connection somewhere?

There was no disruption when it started working again.. Everything was calm and quiet.. Nothing hit the thing. Temp was the same as many many days before that.

I'm happy it's alive again and don't really want to take it off again for inspection. First want to know what the problem might be and where to look. Should I just check all soldered connections? Give it to a shop for inspection?

Thx in advance everyone!

1 Comment
2024/12/02
08:04 UTC

1

IS EE right for me?

I have always enjoyed and been good at physics and math but have been stuck in this dilemma of becoming a doctor. My hometown friends are all in medical school and I feel that might’ve influenced me. However, I have a love for electromagnets and have always found the field of EE to be the most interesting and cool field as other engineering fields have seemed boring (no offense civil). Are there any EE jobs that are interesting and involve working on cool projects?

2 Comments
2024/12/02
07:35 UTC

12

Impressions of POWER Engineers

I am currently considering an entry-level job offer from POWER Engineers in the SCADA and Analytical Services group. The group does a lot of protection and studies work which I am interested in. I was curious what people's impressions of the company are. Particularly, is learning prioritized in new employees? Would you recommend working for a consultancy or a utility first? Appreciate any advice you can pass on to someone entering the power industry!

5 Comments
2024/12/02
07:30 UTC

1

What classes to take for a EE masters if I want to focus on a HDL/FPGA career?

Aside dsp and vlsi what are classes should I take? I'm not interested in anything cs related like computer architecture or cyber security.

4 Comments
2024/12/02
07:24 UTC

2

In internship applications, should I list my GPA from all college courses taken, or just my current college GPA?

So I'm going to be applying to a few internships here after my first semester ends - I've taken a few CC courses, but they didn't transfer to my current institution. Should I include these in my GPA on my resume, or no?

1 Comment
2024/12/02
06:52 UTC

42

Majors harder than EE in your opinion

I know it’s a very subjective question, just an opinion. Or would you say EE is the hardest major?

159 Comments
2024/12/02
06:12 UTC

1

What other components can we use to represent logic gates?

Aside from ics, leds, diodes, and transistors?

4 Comments
2024/12/02
05:25 UTC

0

Hey yall i updated this is the wiring any good now

I connected wires and stuff for like 3 hours and put it on a wooden platform. Rn the problems i see is the capacitator touching the transformer but i will deal with that later. Im just wondering are the wires any good or still a deadly mess (i connected everything to ground too)? Tho if i get conformation that it works i wont plug it in near me ill use a 20 meter extension cable. Also the transformer came out exactly as it is from the microwave ( a 20 year old panasonic)

14 Comments
2024/12/02
05:21 UTC

16

I'm learning basic magnetic circuits properties, can anyone help me with question 19

2 Comments
2024/12/02
03:12 UTC

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