Electrical Engineering V3 - Developers

I need to figure out something that's the equivalent of an EPO circuit. I have a 20A 240v circuit that when a momentary switch is closed (or opened) the circuit disconnects. Likewise it disconnects automatically if the line drops below 100v AC to protect the attached hardware should power intermittently fail like it's done here repeatedly in the past and damage hardware.

[QUOTE=Staneh;51100626]Do you know the estimate cost for assembly all together? Sorry for asking so many questions :v:[/QUOTE] It's impossible to answer without knowing the quantity. If you're producing a low number (<1000 boards), it won't be economical to have them manufactured instead of manufacturing them yourself.

[QUOTE=DrDevil;51102607]It's impossible to answer without knowing the quantity. If you're producing a low number (<1000 boards), it won't be economical to have them manufactured instead of manufacturing them yourself.[/QUOTE] Alright, thanks for the info!

[QUOTE=pentium;51100952]I need to figure out something that's the equivalent of an EPO circuit. I have a 20A 240v circuit that when a momentary switch is closed (or opened) the circuit disconnects. Likewise it disconnects automatically if the line drops below 100v AC to protect the attached hardware should power intermittently fail like it's done here repeatedly in the past and damage hardware.[/QUOTE] You could probably do something with a transformer/rectifier/cap combo to get a DC voltage from the line voltage, then use an opamp with a reference to control a relay. Simple and effective if that's all you really need. The response time might not be that good in that scenario though.

[QUOTE=DrDevil;51102607]It's impossible to answer without knowing the quantity. If you're producing a low number (<1000 boards), it won't be economical to have them manufactured instead of manufacturing them yourself.[/QUOTE] Assembly costs arn't too bad really these days. I contacted a local company in the UK for assembly costs for a small pcb. 2 SMD components & 7-8 Through hole components, they wanted £2.30 per board and a minimum order of £500. I'd say that's quite affordable.

I'm pretty sure I'm not able to afford assembly yet, maybe when I need to make more boards, but it is quite limited now, I just don't want to cut all the holes and link everything on the stripboard because that takes most of my time.

What happens if you've got a 12v 2A Power supply and have some LED strips rated for 12v 6A. Will the output brightness just be lower than it possibly could?

Yeah, if it needs 6A but gets 2A, it will just work at 33% of power. Though it might be way more brighter because our eyes are sensitive motherfuckers.

[QUOTE=proboardslol;51118438]What happens if you've got a 12v 2A Power supply and have some LED strips rated for 12v 6A. Will the output brightness just be lower than it possibly could?[/QUOTE] Worst case: power supply will croak (especially if cheap wall wart). Best case: it'll work, but (as Fourier mentioned) at reduced brightness.

yeah power supply will work at 100% all the time, forgot this fact. thx vanman

[QUOTE=Fourier;51121291]yeah power supply will work at 100% all the time, forgot this fact. thx vanman[/QUOTE] I know worst case from personal experience :v: It didn't croak immediately, but after about 2 years it ended up literally blowing up a [URL="http://www.futurlec.com/Datasheet/Transistor/C1815.pdf"]transistor[/URL] inside it that was part of the regulation circuit.

[QUOTE=Van-man;51121327]I know worst case from personal experience :v: It didn't croak immediately, but after about 2 years it ended up literally blowing up a [URL="http://www.futurlec.com/Datasheet/Transistor/C1815.pdf"]transistor[/URL] inside it that was part of the regulation circuit.[/QUOTE] That's because when your load is low impedance, a lot of the power is lost inside the PSU due to internal resistance. A 6A load on a 2A PSU is getting awfully close to a short.

[QUOTE=DrDevil;51122393]That's because when your load is load impedance, a lot of the power is lost inside the PSU due to internal resistance. A 6A load on a 2A PSU is getting awfully close to a short.[/QUOTE] Yeah, I would not recommend doing it for anything other than testing/playing around.

Nice!

WorkSafe BC came by the office to casually mention while we just spent $10000 installing fume hoods at our workstations for our soldering equipment to shut them up because of the last visit three months ago, we now either need to switch to lead-free solder or close shop. Someone came around with a cart today handing out spools of lead-free in exchange for our spools of leaded. I took one of the green spools, dumped the solder on it and respooled it with leaded because fuck RoHS. There's a mood felt all over the workshop right now on how we should express our opinions on the matter to the bitch upstairs who on her last day reported the company because of the fumes from the freshly painted walls and caused WCB to say [i]WE[/i], the guys downstairs who are operating on their own HVAC loop were the problem. Fuck you lady. We're burning tips and traces and fighting with solder that we're struggling to melt with our irons cranked because you're are an ungreatful piece of shit. Also fuck you too, Garfield. Judging by your voice and your shitty story about a chemical fume accident you have a vendetta out for people like us.

Leaded is illegal to use outside of personal hobbies, education and special-exemption (military, health care etc.) stuff, here. Mildly amazing you actually have leaded solder over there, to begin with. Might want to experiment with alloys other than the shit you were given.

I know lead-free solder gets a bad wrap (for good reason), but I've yet to find good lead-free that flows as well as standard 60/40. Especially if I don't have the time for large boards and a lack of any reflow oven.

I do still have a small amount of silver solder left. I was allowed to keep that but it's expensive.

I've only witnessed silver solder being used for battery terminal soldering, way too expensive for general use.

Gotta be cheaper than HVAC brazing rod. $10 a stick (about a foot long), 15% silver content (they go up to 30% but hoowee that's expensive). :v:

[QUOTE=pentium;51148812]WorkSafe BC came by the office to casually mention while we just spent $10000 installing fume hoods at our workstations for our soldering equipment to shut them up because of the last visit three months ago, we now either need to switch to lead-free solder or close shop. Someone came around with a cart today handing out spools of lead-free in exchange for our spools of leaded. I took one of the green spools, dumped the solder on it and respooled it with leaded [B]because fuck RoHS[/B]. There's a mood felt all over the workshop right now on how we should express our opinions on the matter to the bitch upstairs who on her last day reported the company because of the fumes from the freshly painted walls and caused WCB to say [i]WE[/i], the guys downstairs who are operating on their own HVAC loop were the problem. Fuck you lady. We're burning tips and traces and fighting with solder that we're struggling to melt with our irons cranked because you're are an ungreatful piece of shit. Also fuck you too, Garfield. Judging by your voice and your shitty story about a chemical fume accident you have a vendetta out for people like us.[/QUOTE] Might want to be careful with that attitude, you can land yourself and your company with a nice big fine.

How does the process of programming microcontrollers differ between brands? I feel the need to start learning how to program AVR IC's properly without use of the arduino IDE as I think it'll make switching to other IC's easier. AVR being the choice as I could first try translating some projects done using the arduino IDE.

[QUOTE=scratch (nl);51151998]How does the process of programming microcontrollers differ between brands? I feel the need to start learning how to program AVR IC's properly without use of the arduino IDE as I think it'll make switching to other IC's easier. AVR being the choice as I could first try translating some projects done using the arduino IDE.[/QUOTE] Funnily enough, Arduino is largely based off of [URL="http://winavr.sourceforge.net/"]AVR-GCC[/URL] ([URL="http://www.nongnu.org/avr-libc/"]Documentation on the libraries[/URL]). And then setup that toolchain for your IDE of choice (I personally use Code:Blocks as integration with it is pretty good, but you can use AVR Studio if you'd like). You'll need to do a few more things from scratch like serial routines and handling the ADC, but read through the datasheet of the chip of your choice to understand what registers to work with and then you'll be golden. You'll need to setup some sort of [URL="https://www.amazon.com/HiLetgo-Downloader-USBASP-Programmer-ATMEGA8/dp/B00AX4WQ00/ref=pd_lpo_147_lp_t_4?ie=UTF8&psc=1&refRID=WTF33DZVYFFK5XA0K2SN"]AVR ISP programmer[/URL] to which you can buy or you can use an [URL="https://www.arduino.cc/en/Tutorial/ArduinoISP"]Arduino as an ISP programmer[/URL] which I find to be the easiest. From there just learn a bit of [URL="http://www.nongnu.org/avrdude/"]avrdude[/URL] (Should be included with AVR-GCC/WinAVR from the start) to understand how to interact with the programmer and load up hex files and you're done! TL;DR: Arduino is to AVR-GCC as C++ is to C. You can easily translate your arduino programs over provided you write some functions from scratch. I don't know how to program PICs though, they're kinda a dead microcontroller in my eyes.

[QUOTE=LoneWolf_Recon;51152122]Funnily enough, Arduino is largely based off of [URL="http://winavr.sourceforge.net/"]AVR-GCC[/URL] ([URL="http://www.nongnu.org/avr-libc/"]Documentation on the libraries[/URL]). And then setup that toolchain for your IDE of choice (I personally use Code:Blocks as integration with it is pretty good, but you can use AVR Studio if you'd like). You'll need to do a few more things from scratch like serial routines and handling the ADC, but read through the datasheet of the chip of your choice to understand what registers to work with and then you'll be golden. You'll need to setup some sort of [URL="https://www.amazon.com/HiLetgo-Downloader-USBASP-Programmer-ATMEGA8/dp/B00AX4WQ00/ref=pd_lpo_147_lp_t_4?ie=UTF8&psc=1&refRID=WTF33DZVYFFK5XA0K2SN"]AVR ISP programmer[/URL] to which you can buy or you can use an [URL="https://www.arduino.cc/en/Tutorial/ArduinoISP"]Arduino as an ISP programmer[/URL] which I find to be the easiest. From there just learn a bit of [URL="http://www.nongnu.org/avrdude/"]avrdude[/URL] (Should be included with AVR-GCC/WinAVR from the start) to understand how to interact with the programmer and load up hex files and you're done! TL;DR: Arduino is to AVR-GCC as C++ is to C. You can easily translate your arduino programs over provided you write some functions from scratch. I don't know how to program PICs though, they're kinda a dead microcontroller in my eyes.[/QUOTE] And dont forget that if you dont want to get a programmer but have a Rasp Pi sitting around you can bang it thru the GPIO [url]https://learn.adafruit.com/program-an-avr-or-arduino-using-raspberry-pi-gpio-pins/overview[/url]

[QUOTE=metallics;51150594]Might want to be careful with that attitude, you can land yourself and your company with a nice big fine.[/QUOTE] [U]Fuck WorkSafe[/U]. While they do have a real reason to exist and I do accept that, they constantly go beyond common sense with some of the things they are total Nazis about ([img]https://i.somethingawful.com/forumsystem/emoticons/emot-godwin.gif[/img]) which often does more harm than good and regularly pisses everyone off. Like, we all signed into this job aware that we'll be working around chemicals and materials which carry a high risk of causing cancer or other health issues. I don't need buddy who has never worked a rework bench dictate what is and is not safe for me or everyone else to use to fix shit. It's basically overreaching to cover the ass of the company at their expense.

[QUOTE=LoneWolf_Recon;51152122]Funnily enough, Arduino is largely based off of [URL="http://winavr.sourceforge.net/"]AVR-GCC[/URL] ([URL="http://www.nongnu.org/avr-libc/"]Documentation on the libraries[/URL]). And then setup that toolchain for your IDE of choice (I personally use Code:Blocks as integration with it is pretty good, but you can use AVR Studio if you'd like). You'll need to do a few more things from scratch like serial routines and handling the ADC, but read through the datasheet of the chip of your choice to understand what registers to work with and then you'll be golden. You'll need to setup some sort of [URL="https://www.amazon.com/HiLetgo-Downloader-USBASP-Programmer-ATMEGA8/dp/B00AX4WQ00/ref=pd_lpo_147_lp_t_4?ie=UTF8&psc=1&refRID=WTF33DZVYFFK5XA0K2SN"]AVR ISP programmer[/URL] to which you can buy or you can use an [URL="https://www.arduino.cc/en/Tutorial/ArduinoISP"]Arduino as an ISP programmer[/URL] which I find to be the easiest. From there just learn a bit of [URL="http://www.nongnu.org/avrdude/"]avrdude[/URL] (Should be included with AVR-GCC/WinAVR from the start) to understand how to interact with the programmer and load up hex files and you're done! TL;DR: Arduino is to AVR-GCC as C++ is to C. You can easily translate your arduino programs over provided you write some functions from scratch. I don't know how to program PICs though, they're kinda a dead microcontroller in my eyes.[/QUOTE] You need datasheet anyway to do anything precise with Arduino anyway.

Theoretical here: Could you use a gameboy color as a microcontroller? The GBC has an IR sensor and emitter, as well as a data cable. You can use sdcc to make gameboy color roms, and you can put those roms on a flash cart. I assume that you should be able to use the gbc data cable to control low-voltage stuff

Work had me prototyping a battery retrofit. Had to be easy to install, fast to assemble and cheap. [IMG]http://i11.photobucket.com/albums/a166/ballsandy/Computer%20related/IMG_6052.jpg[/IMG] 60 seconds with a hacksaw, 2" of copper wire, 1" of shrink tube, 1 square cm of double sided tape and one CR2032 battery holder. Ten minutes of work and $2 in parts. The alternative is a total component replacement at $23 per module.

After a bit of messing around, I now can work on stuff without using the arduino IDE. I'm using Atmel studio and avrdude and it seems to work fine. I made a board to program ATtiny's a while back, and it works fine for this as well (I knew adding a bunch of female headers to the board would prove usefull later!) [t]https://dl.dropboxusercontent.com/u/43645231/photos/electro/2016-10-09%2020.12.15.jpg[/t]

Building a humanoid robot, realized I needed small screws/bolts to mount the servos to my aluminium frame. Ended up ordering them online because while the local hardware stores had bolts/nuts that were the right size (M2x20mm), they wanted $0.20-0.33 a piece for them, and I got 100 of each for $12 online. Only problem is now it's taking what seems like forever to get here. Note to self: Avoid Chinese retailers when in a hurry...