Activity for cosinedâ€
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
| Edit | Post #285070 |
Post edited: |
— | almost 3 years ago |
| Comment | Post #285070 |
Hi Andy aka, first off, I gotta say that I am a big fan of yours. I've come across literally hundreds of your responses on StackExchange over the years as a silent reader. You've helped me a lot. Thank you for your help and willingness to share your expertise!
As for why I say triple phase in the ... (more) |
— | almost 3 years ago |
| Comment | Post #285078 |
That is some solid advice; I'll take it. It's always better to do it correctly and safely (with an electrician). That said, I appreciate the information you shared in your answer. It helped me understand at least one way to get 230V single-phase. Thank you Olin! (more) |
— | almost 3 years ago |
| Edit | Post #285070 |
Post edited: |
— | almost 3 years ago |
| Edit | Post #285070 |
Post edited: |
— | almost 3 years ago |
| Edit | Post #285070 | Initial revision | — | almost 3 years ago |
| Question | — |
208VAC triple-phase to single-phase conversion The question: Is there a way to convert from triple-phase 208VAC to single-phase 208VAC? Background: Hi everyone, I am stuck on a project I'm working on. I'd like to convert 208VAC (three phase, NEMA L5-20R) to 230VAC (single phase, NEMA 5-20R) for use with a piece of 230VAC equipment that pl... (more) |
— | almost 3 years ago |
| Comment | Post #284395 |
[In response to the edit of Olin's answer]
Thank you Olin! It always helps to reexamine the causes of things, in this case what's actually at play in causing the heat. I appreciate the explanation. The final sentence addresses exactly what I was worried about; I think you make a lot of sense here.... (more) |
— | about 3 years ago |
| Comment | Post #284395 |
Thank you Olin for your response! My idea of using a PTC fuse/polyfuse was to prevent the motor from heating up if something was to go wrong on the motor controller or microcontroller side of things. With the polyfuse wired in-line/serially with the motor, it would limit the current to the leakage cu... (more) |
— | about 3 years ago |
| Edit | Post #284393 | Initial revision | — | about 3 years ago |
| Question | — |
PTC resettable fuse leakage current Intro Hi everyone, I have a question about the practical use of a PTC (positive thermal coefficient) resettable fuse. I've never used one before, but I'd like to add one to a DC motor circuit to prevent it from overheating when running continuously. More features being used I already have two mo... (more) |
— | about 3 years ago |
| Comment | Post #282721 |
Makes sense. It was definitely poorly worded on their part, but they had lots of information to include. I don't blame them too much. Thank you for revisiting this! (more) |
— | over 3 years ago |
| Comment | Post #282672 |
@#54107 Please use MathJax next time to format your equations. You can use it directly on this site when typing in your questions. The Math community has a great guide on how to do so: https://math.codidact.com/help/formatting
(more) |
— | over 3 years ago |
| Comment | Post #282593 |
You're exactly right... Thank you Dave! I updated my post with a new schematic. (more) |
— | over 3 years ago |
| Edit | Post #282593 |
Post edited: |
— | over 3 years ago |
| Edit | Post #282593 | Initial revision | — | over 3 years ago |
| Answer | — |
A: Critically damped oscillation issue I don't know how to attach images to a comment thread, so I will just open up an answer for this. I redrew the schematic for you to reference. Image alt text I think that symbol at the top of your drawing probably represents a switch. We are likely looking at damping when the switch closes. We ... (more) |
— | over 3 years ago |
| Edit | Post #282543 |
Post edited: |
— | over 3 years ago |
| Edit | Post #282543 |
Post edited: |
— | over 3 years ago |
| Comment | Post #282543 |
There is no substitute for experience... Haha. Thank you Lundin! (more) |
— | over 3 years ago |
| Comment | Post #282545 |
You are completely right about how to interpret the drop-out voltage table. I actually thought the same thing you do, but probably did not represent that well in my write up... I should have emphasized that I expect about a 200mV drop-out with my approximately 0.1A load output current. The maximum lo... (more) |
— | over 3 years ago |
| Comment | Post #282545 |
Thanks Olin!
I agree that it is quite long. I added a section at the top clarifying what the question is. I am thrilled you also think the datasheet is a bit awkward. On my end, I really err on the side of me making mistakes rather than the people writing the datasheets, lol. Case in point, I did ... (more) |
— | over 3 years ago |
| Edit | Post #282543 |
Post edited: |
— | over 3 years ago |
| Comment | Post #282543 |
When the Arduino is connected (as it will always be in the application setting), it will always be drawing more than 7mA, so this is more of a theoretical circumstance. With the Arduino connected and the new resistor values, the output voltage according to the oscilloscope is now 11.7V, which is wha... (more) |
— | over 3 years ago |
| Comment | Post #282543 |
Hi Lundin, I tried decreasing the resistors and in the process realized that I calculated the bleed current incorrectly. R1 and R2 combined serially are what should be in the calculation, not just R1 like I used to have. This explained why the voltage rose above 11.72V when the load was disconnected.... (more) |
— | over 3 years ago |
| Comment | Post #282543 |
Yep, I like your suggestion about using smaller and more standard resistor values. I will give this a shot soon and report back what the outcome is. Thank you! (more) |
— | over 3 years ago |
| Edit | Post #282543 |
Post edited: |
— | over 3 years ago |
| Comment | Post #282543 |
Hi Lundin, thanks for the quick response! So you think the resistor values could cause the output voltage to drop like that? I didn't even realize this could be a problem. Resistor values aside, was the rest of my interpretation on how to use the LDO regulator correct, _should_ the output voltage be ... (more) |
— | over 3 years ago |
| Edit | Post #282543 |
Post edited: |
— | over 3 years ago |
| Edit | Post #282543 |
Post edited: |
— | over 3 years ago |
| Edit | Post #282543 | Initial revision | — | over 3 years ago |
| Question | — |
Trouble understanding how to use adjustable LDO regulator The question being asked Ultimately, I want to know why the output voltage wasn't the expected (via calculation) 11.72V when the estimated drop-out voltage at the 0.1A load was about 200mV. The input voltage to the regulator was 12V. Hi everyone, first off, I wanted to say I am a big ... (more) |
— | over 3 years ago |