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- Опубликовано: 13 окт 2024
- An enhancement to my recent pond pump project - pump speed control!
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Having installed a pond pump there came the inevitable "upgrade" request: "Can we make the pump more controllable?".
Well YES, we can, as it happens.
Products
Any PWM controller will adjust the speed of a motor like this. But I couldn't face building one, so I bought a cheap one off the Internet (Amazon UK, actually):
amzn.to/3Be0Z8p
You can get them cheaper if you are prepared to wait for a while, see this one from AliExpress:
s.click.aliexp...
Identical products (apparently), just a different price. Pays your money, takes your choice.
I found a video on RUclips by @RJ Imagination that demonstrates the same circuit (pretty much):
• PWM using OP-amp | how...
www.circuits-d... (his article)
► More info in my GitHub:
github.com/Ral...
I also found a circuit diagram for a 555 Timer PWM too:
www.build-elec...
A reasonable MOSFET for use by Arduino users (ie a 5v GPIO voltage) not suitable for ESP32 use (not without a level shifter):
www.infineon.c...
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(Special thanks to Michael Kurt Vogel for compiling this)
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► More info in my GitHub:
github.com/Ral...
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Just a tip on Mosfet/IGBT gate drivers, I've had good luck using HCPL-3120's from china. They're basically optocouplers with a built-in totem pole driver that can easily drive a handful of big mosfets in parallel. They're REALLY simple to set up inline with your arduino and provide isolation to it which is always welcome, and at around 50 cents a piece are pretty affordable.
And if you just want to be an animal you could use an L293D driver which could drive up to 4 separate channels, but it's an out of scope use. Nowhere near as versatile though since it's a 5v logic level input and provides no isolation, along with that it can only work at up to 5kHz. But works in a pinch and is a lot cheaper since they're used all over the place.
Anyways just wanted to chime in with that. With the HCPL you can do some pretty neat stuff since it's isolated, all you would need is a separate isolated power supply and you can switch a high-side gate, which is what you need for inverters and such (provided you're only using N-channel fets). IMO its never a good idea to connect a power transistor making all sorts of noise directly to a microcontroller. It's insane how much electrical noise travels through everything especially when you're on a proto-board.
Hmm. It's a tad unfortunate that the operating voltage for those drivers (the datasheet says) is 15 to 30 Volts. Otherwise they don't switch on. More here: docs.broadcom.com/doc/AV02-0161EN The idea is a good one, though.
I've had some optocouplers in my Pandora's box of parts for some time: a PC817XNNSZ0F which just contains an IR LED and a transistor. It's described as a plain old DIP 4-pin optocoupler. What it doesn't say is what the _minimum_ voltage is across the collector/emitter; perhaps it doesn't matter. The max voltage is 50v though. I really shall have to try this out one day soon.
@@RalphBacon the minimum voltage of a normal optocoupler is basically the voltage drop, in the case of the PC817 it's minimal, like 0.1v. the problem with the PC817 is 1: their switching speeds are quite low (like 20khz max if you want to have good control of duty cycle, but 80khz otherwise) and 2: they can't handle much current, like 30ma. Theyre really good for isolating IO ports and level shifting.
Interesting stuff about the HCPL3120. I'm going to try running one at 12v to see if it runs. It might just be that 15v minimum is recommended because most IGBTs are recommended to be driven at 15-20v to make sure they are as conductive as possible.
Yes, the other Mic. sounds much better. Love the large LED Array!
Good to know! I'm reverting to my original mic next video!
@@RalphBacon - It also took more volume increase to hear.
I Had to have one a few months ago, I just used the trusty ol NE555 with a lm7805 running it from the input voltage and used the output from the 555 to drive the gate of a irfz44n N channel FET with a small heat sink, worked a treat. 3d printed case and I was up and running, cheap, no waiting for post and more reliable than ordering from china. I don't buy anything that I can build myself, good luck with your project and have a blessed Christmas ...
Sounds just like I might have designed it!
I do have a soft spot for op amps. Many, many moons ago (70s) I got into electronics because I wanted a synthesizer. Moogs, the first and only source of these instruments cost as much as a decent 2nd hand car. So, I figured I would try and make one. The heart of a synthesizer is a bunch of op amps configured as voltage controlled Amplifiers (VCRs) or Voltage controlled Oscillators (VCOs) and Voltage Controlled Filters. All these modules create sound by feeding the output of one module into the control input of another. Now, you might be visualising a panel with myriad knobs and a patch board with cables plugged into a matrix of holes like an old fashioned telephone exchange. Well, I have to disillusion the reader. The product of my project was many tobacco tins, each with 3 knobs and 2 sockets, arranged in a a maze of cables. Any subscriber should just remember one of Ralph's projects to get the idea. Merry Xmas Ralph.
😲 You mean my projects are messy, Michael?
On the prototyping breadboards they get messy very quickly. The worst one was the ESP32 Web Radio, dozens and dozens of DuPont cables. But it worked!
Thankfully the PCB version was very neat!
Nice one Ralph, hope your fish have their thermals on for the next few day's !...cheers.
It's certainly cold outside. I could write a song with those words. Oh. 🎶Someone beat me to it.
I like the idea of thinking about other effects of a circuit and their ramifications. Keep up the good work it keeps me thinking all around a subject.
Thanks, will do!
If I may, I would suggest to review the choice of MOSFETs. There is a trade off to make between RDS,on, switching frequency and power wasted in the FET & driver. In simple terms to lower the On resistance of the channel, it needs to be wider and this corresponds to higher gate capacitance. The switching happens by charging and discharging such capacitance, putting a strain on the gate driver. The higher current peaks in the driver leads to higher heat and the limit on the driver current leads to the MOSFET spending a longer share of the cycle in linear region.
Since you pretty much know what range of current the load will need, choose a MOSFET rated for a little more than that (50% more, possibly 100% more). Among the FETs rated for such current list the ones with a reasonably low RDS,on at the Vgate-source available in your circuit (6mR seems an overkill to me). The next step is selecting the MOSFETS with smaller gate capacitance and smaller gate charge but still low enough Rds,on.
The HY1707P has an input capacitance of 2140pF which is huge for the job you need it to do. Driving such a large gate with something like an OpAmp could prevent the FET from ever operating in the On region because, at 4.3kHz, Vgs never actually reaches an high enough voltage.
Indeed, the output wave form did look quite slow (at switch on) maybe the gate capacitance was to blame for that. This circuit is so simple that I'm still tempted to roll my own one day. I could get the ESP32 already present in the pond pump controller to do the PWM. Then it could be controlled from my phone too.
You have a loyal following here Ralph - lucky man. Take care and thanks for sharing your immense knowledge.
I appreciate that! Not sure my knowledge is immense, though. You know the saying that a little knowledge is dangerous!
A good place to find TTL MOSFETs is old PC motherboards. The MOSFETs around the CPU socket for the VRM are usually controlled with 5v or less. A little shot of hot air from a heatgun or hot air station and they pop right off and they usually handle quite high amperage.
I use Motherboard Fets all the time. They work nicely driven by a microcontroller.
@@romancharak3675 yeah. i buy PC's from yard sales and work on alot of them for ppl so instead of throwing away all those parts i sit out in the building with a heatgun and tweasers and strip parts to fill my parts bin. then when its winter time i build stuff.
Sounds like a great source of components, Mike.
Hi Ralph. When I built my ventilator prototype, I was getting horrid noise out of the motor windings on the 12V windshield wiper motor I was using until I adjust the internal timer values on the nano. I found this bit of code:
// adjust internal timer for PWM on pins 9 and 10 to reduce motor whine.
TCCR1B = TCCR1B & B11111000 | B00000001; // set timer 1 divisor to 1 for PWM frequency of 31372.55 Hz BEST
// TCCR1B = TCCR1B & B11111000 | B00000010; // set timer 1 divisor to 8 for PWM frequency of 3921.16 Hz
Once I did that, the motor was silent from then on.
Maybe if you build your own PWM controller, you'll have a much quieter output.
Best wishes,
Gord
That's exactly as I described it in video #15 here ruclips.net/video/e2CPnmLmSws/видео.html in February 2016! Small World.
@@RalphBacon FYI we had a project where we had to do the frequency adjustment when running a diode laser driver. The laser driver would only work on higher frequencies. Thanks for the video.
Two things spring to mind. How does the PWM frequency interact with the motors inherent frequency? The timing of it's commutator brushes. I assume it's a DC motor.
The other things is. whether it's spinning or not a motor coil is an inductor coil and the other thing you pump a PWM wave into an inductor for is a boost convertor. You'll certainly need to address the fly-back/freehwheel inductive pulses.
PWM in the case of motors, the only ones I've played with the PWM is not driving the motor, but the brushless motor controller.
I don't know whether either of the pumps have brushes or not. But the back EMF diode is certainly a good idea. Now, where's my soldering iron...
My extensive research reveals that goldfish can hear up to about 4000Hz, with larger carp species being able to hear to 7-9000Hz. So anything you can't hear, your fish should be OK with :)
TO220 packaged MOSFETS typically have a die-to-ambient thermal resistance of 62 degrees per watt, and given the maximum die temperature is about 90 degrees above ambient (~125 degrees) you shouldn't dissipate more than 1.5w in a MOSFET that has no heatsink; in this case 1.5w in 6mOhms I^2 = P/R = 1.5/0..006 = 250 so I=sqr(250)=15.8A per device. They will get Hot Hot Hot!
The good news is that I increased the frequency to around 4kHz and the MOSFETs are tepid, at best with my little pump. But as a solution it is crying out for a "proper" design... I'm keeping this one on my "To Do" list!
Dear Ralph. Having bred aquarium fish outdoors, I have found that the bubbles from your air-stone will give sufficient water flow in such a small tub. In fact, I do not add any circulation to my outdoor tubs at all. Still water is totally quiet and peaceful.
Still waters run deep, Roman. Yes, I'm pretty sure I don't actually _need_ the water pump for the fish to thrive but it's nice to have on in the summer, especially.
I recently build a bog standard pwm speed controller for a model train using the trusty NE555 and Irf540. I was quite satisfied about the speed control. Also at low speeds. I see nothing wrong with this setup 🙂 (In this application.) Cheers!
Thanks for that feedback, Piet. Always good to know that the trusty 555 is still being used. This module works well enough although the output could be a lot cleaner (square wave) with a higher frequency.
You mentioned your thinking of getting a 3d printer. I've had a Prusa Mini+ for 2 years and would thoroughly recommend it. Its enabled me to print no end of enclosures etc. and for 3d cad software I use Autodesk Fusion 360 which is excellent. Good news is its free to us hobbyists else for commercial use its very expensive and the limitations of the free version are minimal. There are loads of youtube videos to learn it eg. Kevin Mcaleer's channel. Hope this helps
Yes, I'd love a Prusa (whatever model, turn on and use) but Autodesk Fusion 360 is something I tried to learn but it took FOREVER even to get the simplest shape on screen (I was following their lessons). I need something really simple just to print enclosures, initially.
@@RalphBacon Have a quick look at OpenSCAD, its a programming language for defining 3D shapes, and especially suited for making enclosures. There's a number of free box-making programs for it people have written, and of course you can hack about with other peoples OpenSCAD designs for your needs. Free download and of course you can try it without needing a printer.
There's a number of smaller 3D printers that have come out in the last year that are in the £200 bracket but have advanced features like auto levelling and direct drive that previously were the preserve of much more expensive printers. And if you don't get on with it you'll know what to look for in a different printer before you get too invested in it. I put off getting mine for ages and now I find so many uses for it.
@Ian_Rolfe thanks for the heads up (and Real World experience too). I shall check out OpenSCAD and see how it feels 👍
@@RalphBacon There's a pretty good series of tutorials on the OpenSCAD site that helps to get a "feel" for how it works and the approach.
I reckon that for Mk2 you should just do the PWM from the ESP module to both turn it on and control the speed. Then the minister of everything can control the pump flow from her phone.
We control a lot of 3phase pumps by varying the frequency of the supply, still getting their 415VAC but at above or below 50Hz to vary the speed.
Certainly if I ever did a Mk2 I would let the ESP32 control the speed, and from the phone too. I wonder if businesses go through this type of iteration with their products?
@@RalphBacon oh they undoubtedly do! At least if you ever run short of project ideas you can roll out a Mk2 of something you did earlier. Would still be just as technically interesting even if we’ve already seen you make an XYZ already
Off course, you will need water movement in the winter months to keep the water from freezing over. Otherwise, your fish won't get enough oxygen. Cheers from Canada!
Indeed. I know goldfish are hardy creatures (I'm sure I've seen a film where they have been frozen in ice but come back to life) but our ones get a stream of bubbles every 15 minutes overnight and all day long to ensure they get enough O2.
To get 80A’s through that you would need a unobtainion heat sink. Power dissipated would be I^2* R so 80^2*0.008 is 51W’s. But you would need to look at the thermal resistance of their package, as it not limited by the max current but more by how fast you can get the heat away from the junction.
I found that with most max current figures it is almost imposable to use them anywhere near it. And again this would be stated for 20 deg C, so you would need to derate it for most applications anyway.
big numbers sell more parts as china has found out.
Indeed. I bought a 30A SSRs a few years back and discovered a 10A SSR inside the package. Big Clive had alerted me to this ruse!
Thanks Ralph. I nearly followed that!
It's a pity I didn't managed to explain PWM well enough as I went along for you. I have some beginners' videos that do explain it a slower pace though, videos #14 & #15 ruclips.net/video/yZ53HbSYNqU/видео.html
LCSC lists the HY1707 mosfets @ $0.56/each. I bought a bunch of very similar HY3403 mosfets from them a while ago (probably because they were even cheaper @ $0.37/each.) I've used these a few times and they seem perfectly fine. These are rated at 30V/140A. Pretty sure however, that 140A needs to be read as the ABSOLUTE MAXIMUM 'momentary' peak current ... with a heat sink. I mean ... I also enjoy welding, so I have a pretty good idea what 100+ Amps will do to any old piece of metal. Hard to imagine that these could sustain this kind of current load for very long.
As for PWM ... I was working on a similar project a while ago. At first, I tried making a 555 work, but ran into issues* and became frustrated. I finally settled on generating the PWM with an ATTiny412. These are cheap ($0.40/each), easy to program, and worked perfectly for me.
* Don't recall exactly, but I think the issue was that I needed a duty cycle less than 50%. I couldn't do this easily with the 555, so I tried inverting the signal. This sort of worked, but caused issues because the signal's default voltage was now high ... thus keeping the mosfet turned on. I melted a few things. It happens.
Yes, the less-thn-50% duty cycle on a 555 was what I was referring to in the video.
It _can_ be done (using a diode or two, apparently) but when I was thinking about this entire project and whether I should roll my own PCB inside that case, a simple Arduino-compatible chip was at the top of my list.
I have several naked ATMega328Ps (both DIP and TQFP32), ATTiny85s (no native PWM but we could bit-bang), and even an ATTiny167 (which I was hoping to use in a project, but they are now rarer than hens' teeth).
The "problem" with hardwiring electronics (such as using a 555) is that once done, that's it. No easy expansion or tweaking route. Using a μC is a whole different ball game.
Yes, the 140A was just a paper-based specification; in the Real World I suspect a decent heatsink and decent wiring would be called for, when even approaching that level of current (that's 10 x 3KW kettles) 😲
For PWM you really need 2 555s. One generating the base frequency and the other triggered by it in pulse mode.
Or a 556? I've used those before, fewer overall pins and a single chip!
Just out of interest, why don't you have a 3D printer? Not saying you should have one at all. Just wondered what holds you back. I use my resin printer more now than FDM, as it's so acute and fast for shallow objects like cases. It's compact easy to use, and not as messy as some would have you believe. Love the videos keep up the good work.
Who says I don't have one? Oh, OK, I've recently acquired one and we will no doubt talk more about that in future videos!
@@RalphBacon you do mention at the end of this video, that you don't have a 3D printer, and can't make your own enclosure.
Hope you are enjoying your new printer and look forward to it making an appearance.
Thanks Ralph
You're Welcome, Wayne, thanks for the visit 👍
Seeing the waveform it looks like the IC turns the mosfet on too slow. Increasing the switching frequency could cause the mosfets to not switch fully on.
I've had the same problem controlling a PC fan once, and I lowered the switching frequency to a few Hz. That worked fine for me.
Yes, the waveform is a bit slow but seems to work "OK" although I noticed it was warmish to the touch even on my low amperage pump use.
If I had the time, I'd replace the circuit with my own that could then start with the full 12v 100% for about 1 second before reducing it to whatever the pot indicates - that allows a lower speed without stalling. And I'd get some decent square waves!
@@RalphBacon It should be "easy" to modify the existing one with a startup boost using e.g. a RC circuit.
I would prefer to see an arduino base or maybe for the fun of it, with an esp8266... would be some kind of a challenge... And thank you for this one!
Yes, a home-grown Arduino-based PCB would be awesome!
Lol leave it to Ralph to worry about the nerves of the fish. If you go too high you might upset some bats.
OMG I had not thought of the bats! Or dogs! Well, the good news is that the fishes do not seem to mind the current frequency of about 3.5KHz so I might leave it there (for now).
Hello Ralph, gr8 video :) As a side issue, do you have any videos covering soldering with eyes that aren't getting any younger?
I wonder if a USB microscope camera would help?
I find a USB microscope fantastic but not for actual soldering (not usually, anyway). I use it to _check_ my soldering, once it's been done. It's saved my bacon on many an occasion! The smaller one was "only" about £85 but I invested in a much larger one as my eyes got real bad and that's what I now use.
What I find very useful for soldering is what I showed in a recent video starting at this point: ruclips.net/video/1OAVkZy8ZXE/видео.html
Links to the products I mention in the video description!
Incidentally, trying to solder using a USB microscope is difficult because everything is a bit too big, things move too easily and it's not 3D (ie stereoscopic, although you can buy such microscopes for big money, in fact Louis Rossman uses one all the time).
@@ForwardGuidance I have tried a USB microscope, but looking at the screen is dis-orientating.
@@RalphBacon Excellent thank-you. After making a real hash of soldering a DB9 connector, I've decided it's time to find a better way.
Yes, try those "jewellers glasses", you get many different strength lenses. I use them all the time.
My name does NOT start with a @ nor does it contain an underscore, though there is a space in there. Screw you, RUclips with this stupid "handles" nonsense...
I'm noticing that those chinese designers sure seem to like the 358 dual op amp chip. My guess is that the circuit is likely to be an integrator and a schmitt trigger. A real easy way to make an oscillator.
I was in a thrift store a while back and while I don't often find anything much useful in their electronics offerings, I did notice this little box. It was quite siimilat to the one you show here, with voltage input and a couple of other terminals for the load. On opening it up to look, I did see a 555 chip and a MOSFET. I haven't tested it out yet, not having an immediate use for it, but I figure that for 99 cents it was worth that for just having the box! :-)
Absolutely! As I said, the cases are the hard bit to get right! Now, @Roy_Tellason, what's your handle?
The only problem with increasing the PWM frequency is that switching mosfets have to go through their linear region and dissipate a lot more heat on each rising and falling edge, so as frequency increases, so does the heat generated in the mosfet. That isn't helped by power mosfets' relaively high gate capacitance (often in the order of nanofarads) which slows down any fast edges that are driving it. Going from hundreds of Hertz to thousands of Hertz probably isn't going to make much difference in low power applications like yours, but we shouldn't be getting the impression that we can simply raise PWM frequencies without limit.
I can go to 1MHz without issues, but I guess it depends on how much current you're drawing in your particular application, and what the RDSon resistance is for your particular MOSFET.
@@RalphBacon You're quite right that the current drawn will be a limiting factor.
However, the Rds for any power mosfet is not a limiting factor in raising the PWM frequency, because the Rds only controls the dissipation when the mosfet is on.
The key parameter is the gate charge or capacitance because that limits how quickly the mosfet transits its linear region where the product of Vds and Id is at its peak. Raising the PWM frequency means the mosfet spends a larger fraction of its time in the linear region, hence is limited by the ability of the driver to push charge in and out of the gate.
could make it so the mosfets use the case as a heatsink (bottom plate),
if going for a new pcb would space the mosfets left/right
Yes, using the (metal) case would be my choice too for a heatsink. Although it's all working now, I am still keeping this project "open" for a replacement circuit board in the future.
The safest way for the fish may be to ditch the electronics and simply divert part of the water back, before it reaches the outlet. :-)))
What outlet? If I have an outlet it's going to be called a leak. This pond is self contained (and that's the way it will stay, I hope). 🐠
Another great video Ralph. Thanks for the knowledge you share. Time to get a 3d printer? What's a couple of hundred £s for a man of your means :)
It's not just about the price, it's about how to use the thing in a meaningful way. By that, I mean I want to be able to use it (over the course of time, say 6 months) in much the same way that I now design PCBs. It's an uphill learning curve for sure.
@@RalphBacon Hi Ralph, You'd have it making enclosures, spacers and lots of useful things in no time. As for the learning curve on using the thing and CAD: Not gonna lie, it is there, but you are more than clever enough to enjoy it.
Has the heron found you yet? I gave up on pond fish after losing so many. There are loads of supposed preventative measures, but really the only thing that works is total exclusion, and who wants a huge net around their pond? Good luck.
The heron has not found us yet, and I'm considering a decoy heron but I've seen anecdotal reports that they don't work. 😔
@@RalphBacon I eventually decided that an overflying heron sees the plastic heron and thinks "Hmm. Plastic heron, there must be fish there, let's go and have a look". Certainly the heron walked straight past mine without giving it a glance. I do think it was pretty much always the same heron, who probably flew a pattern around the ponds in the neighbourhood, but anyway once he'd found me he never forgot. My father-in-law had a medium-sized but deep well-constucted pond, and had some success with fishing lines strung at about 24" off the ground around the whole pond on short wire poles. The theory is that the heron doesn't like stepping over the line, and the line is close enough to the pond that they can't land inside it from the air. A little unsightly, but also a royal pain when you need to get into the pond, removing the wires etc. As you can tell, having given up on it all, I'm a bit of a pessimist about herons.
So what you're saying is that not only do decoy, plastic herons not work, they actively encourage real ones to have a look! 😲
@@RalphBacon You've made me remember one contraption I never tried - a squirter. People, I believe, have used them to keep cats etc off bird tables, and I think I read on a forum somewhere of somebody using the same trick for herons in the pond. I'm not sure I ever believed in it, but anyway it was too much contraption for me to even try. At least you wouldn't be daunted by the sensors, electronics, power etc. And it might be more feasible for a barrel pond than a standard small garden pond. Might be fun to make, and provide some youtube content, even if it doesn't work. You may be able to get a version for bird tables somewhere on the internet, and then adapt.
Although the MOSFETs are rated at 40A, but that PCB wouldn't be rated anywhere near that.
In fact the terminals are bit light on too.
The actual device says it's rated for 30A. Whether anything other than the MOSFETs would survive that, well, who knows!
Are you now sponsered by Lidl 🙂, on the fish side have they survived the frosts???
Goldfish can survive the winter without problem, as long as the water doesn't freeze over.
Squeak !!!!!!!!
@@andymouse Cheese>>>>>>> toasted
Barrel Pond has frozen over but the bubbles keep an air gap working nicely. The water pump is also still going strong. It all looks a bit weird but I'm sure the fish are still under that ice somewhere!
MOSFET's only work properly with a heat-sink. Even if you a a small heat source it needs somewhere to go. Shouldn't Q1 also have a flyback diode, for back EMF?
Not at all, there is a temperature range where the MOSFET will work quite happily without a heatsink and all the information required to achieve this for your particular application is clearly laid out in the device's Datasheet. As an example take the TO92 packaged device that will sink or source 100mA, perfect for low power applications. The person who drew this has not shown the ' Body Diode' that is present in this device (IRF540) and in a vast majority of them, again this is contained in the Datasheet that I just downloaded which is something I recommend for any design work.
@@andymouse The internal diode can protect the MOSFET from reverse voltage, but not from overvoltage. Cheap standard core brush motors can generate very high voltages.
@@dunk_law Yes indeed, better safe than sorry, commercially the don't bother but I might include one again it's not my design and i'm sure Ralph is aware but thanks for your input...cheers.
@@andymouse I was forgetting that it is driving MOSFETs in parallel. I have designed some with three. This distributes the heat and may be cheaper than a heatsink. Don't do many though, I am more on the IGBT side of things.
@@dunk_law Those are fascinating devices too, often overlooked.
How much would pcbway have charged to make the case? :)
Good question. I should have asked but I had time constraints. I will do that next time. That way I could design an ultra-simple, bespoke case but without the high cost of buying and setting up a 3D printer myself. Let the experts do the actual printing!
I wouldn’t the solder those tabs…just bend them tight down to clamp the pot in place😊
Why, oh why would you say that, Flash? Bending them down is certainly step 1 to a physically robust mounting but why not actually solder them (like USB sockets etc)?
@@RalphBacon Just in case you might need to Change the pot.... Sometimes those little guys get skittery. But you can of course solder them too✌🏻😁I have the 'if that goes wrong, I can fix it fast' syndrome 😎
If this pot ever went funny (technical term, obvs) I would rip out the entire board and redesign my own! Now that you've mentioned it, I'm kinda hoping it _will_ go wrong soon!!!
Ik heb deze aangesloten en deze brande
gelijk door 2 keer
Did it break down after the second time?
🙏🙏🙏
Hey, Yogesh, always good to see you here.
Which is it Ralph pcbway or jlpcb???? Huh hahaha
Both, Joey! Very good products from both suppliers (although I'm sure they would both disagree with that statement 😲). But I'm neutral.
3:25 Ralph - Lord of the weed! 😂
As your mother is living in Germany, you might know about lord of the weed parody from the 90s!
ruclips.net/video/e4FSbGVrLS8/видео.html
I'll admit I did not know about this film; I'm guessing it's a cult classic among students?! I'm 10 minutes into it at this moment, must watch a bit more...
@@RalphBacon don't try too hard to understand everything! And yes, this was cult back in the days! Like your channel is nowadays! 😉
Good stuff, simply explained for us dabblers. Let's hope RJ IMagination cross posts to boost your channel.
You never know, Hari. But I was happy that they had already built something I could show everyone. So far, working well, but now I have 2" of ice on the pond (in sheets, as the bubbles have stopped it forming correctly).
@@RalphBacon Your next project then is to switch on an air bubbler as the temperature approaches zero to stop the ice forming. A complete solution to all your fishy needs.😊
it's ruined the careers of a many a EE!! buying electronics from house of the rising sun! ha..ha....kidding!
great vid as usual !! next he'll tell me he'd like an English muffin, rather then a biscuit. to go with some gravy
& eggs!
Good grief, "gravy" with biscuits, it can only happen in the USA, or maybe Canada.
If I hadn't visited Florida on several occasions I would not have a clue what you were suggesting in your menu, but I even got to like sausages, bacon (of course) with maple syrup! But Grits you can keep, blagh 🤮I really tried to like them but they just make me gag.
Biscuits and gravy ! you have a screw loose old chap !
@Ralph S Bacon it's an American thing. Tea biscuit type dough covered with a white flour gravy with fried breakfast sausage and pepper corns you can't actually taste. I had an aunt from Georgia visit when I was young. Hahaha they put the same sauce on chicken fried "lightly battered fried meat that's not chicken".
Use a H bridge?
In this particular case, an H-bridge doesn't give us an advantage because we don't need to change the direction of the motor and to get speed control we still need to supply the MOSFETs of the H-bridge with a PWM signal (from a 555 timer, for example).
@@RalphBacon oh, sorry, for some reason i thought you want to control it with esp or any other MCU.
Well, I _could_ control it with the ESP32 that's next to it (if I redesigned the Pond Pump Controller board, I would do this). But I still would not use an H-bridge, which is much more useful controlling bidirectional motors such as those found on models (cars, etc).
You don't own a 3D printer. You might need one soon. I got 11 printers right now, too many for you. I might teach you how this thing goes. Best go cheap one under £150, can't go wrong. Or you can let PCBWAY make you one, not cheap in my case.
Yes, I know I need to sort this omission out but first I must find a 3D printing CAD program that lets me print, for example, simple things like enclosures (with lids).
I've had a few suggestions (and I don't want any suggestions in the vein of KiCAD for PCB design, that would put beginners off forever).
Lake weed
Smoking it, by the pond you mean? 😁
LM358, that explains the crap rise time, ...NOT GOOD!
Well, it's not exactly a square wave, that's for sure, Steven. But whilst it's not good, it seems to be "good enough" for this particular use. Mind you, putting a lot of amps through this (which I'm not) might make the MOSFET hotter than it should be with a slow rise time like that.