The circuit diagram for your 250w to 5000w PWM DC/AC 220V Power Invertor is not very legible.Can you e-mail me a better copy?
Topic by AkhbarB | last reply
I am using micro controller in a project that has a set of functions (API) that can be used for a plethora of things.. (just up to you to program it that way) LOLIt has a PWM control... which i am trying to use to FADE in (and out eventually) a high powered LED (LUX III to be specific).. the problem I having is that at a certain point (say at 50-60%) of full brightness I see a VISUAL jump in brightness.. Im trying to get it to be smooth the whole way through to 100%more or less the code is like:PWM = PWM+2which I then wait 10 mSecs and loop it again...I have tried to put in some conditional checking to check to see if the current level of PWM is at a certain threshold..and then only loop it again after a longer delay (say 300mSecs) or something..I tried to search.. ut Im not sure on how to get a CONSISTANTLY smooth fade...ot smooth to say 50-60%..then a visual jump in brightness and then smooth to 100%..any ideas or links on the subject are appreciated.Thanks
Topic by xl97 | last reply
I have a circut with the following wiring and it works for what I have been doing, but I wan't to be able to dim the LED with PWM on the arduino. Right now the light is running at about 50 for the length on the analogWrite. There is really no difference between 50 and 255 in my opinion so I think something may be wrong. When the length drops below 20 the light doesn't even come on. This is for a bike light project and electronics aren't my strongest area. I am guessing there is some period of time the MOSFET needs to switch on and off and the arduino's PWM is just too fast for this but I am not sure. I have access to an oscilloscope so I can test to see if everything is working correctly as well. I just get meaningless jitter with an inner oblong sine wave when I have attempted to use it, so where would be the best points to attach the scope to get some meaningful data. (anywhere I wrote PMW i meant PWM). I would like to point out that the LED is Rated for 13V and I am running it on 11.1 V, so no problems there. Aslo I got it working using a 10k resistor between the gate and ground, the arduino, on PWM mode doesn't sink the current very well. I have included the correct diagram.
Question by seedorfj | last reply
I have a couple questions about driving motors from the arduino (I have a boarduino) - First off, these motors are from various walkmans and I think each one is rated for 1.7 volts. - If I need a transistor, can i use a 2n3904 (since these arn't giant motors) - How do I protect against the emf? The motors need to work going either way (clockwise or counter clockwise) - How would you program it so that the motor can go either forward or backwards?
Topic by guyfrom7up | last reply
Ello mates,so i biult a pwm dimmer acording to https://www.instructables.com/id/PWM-dimmer-using-NE555-and-MOSFET-with-DIY-alumini/ but its kinda different,i used irf530n and ne555p ic, And when i connected all of the components with a 12v source it happens nothing except that little spark comes on gnd with adapter? Help please ?
Question by JohnSmith-Workshop | last reply
I am currently working on a robotics project, and need a bit of help. I have this H bridge, and would need to control it via PWM. Speed control isn't necessarily what i need, though i wouldn't mind. (In4 i should have just bought an ESC) The whole bot is controlled by PWM (All servos) except for the two DC motors that i have on it -- One for forward and backward, and another for rotating an arm. How would i control the H Bridge with PWM? Which pins would i connect what to?
Question by RocketPenguin | last reply
I'm building an ROV for the MATE ROV competition with a high school team this year. For this year's competition, we've decided to control our bot via an Arduino Mega, and we're using PWM to potentiate the thrusters. As the person designated to electrical, I fortuitously have no idea how to set up an intermediate step from the Arduino to our thrusters. I've looked into H-Bridges with both Relays and Transistors, and defaulted to the transistor. How would I choose what transistor to use though? I've tried several (all BJTs) and they're giving me nothing but problems. Should I switch to a FET? Should I use a P type and an N type, or only one? What specs should I purchase them with? Do I ask too many questions? Help! (I'm trying to control a 12V 6A motor with a 5V Pwm signal. Thanks!)
Question by unununium | last reply
I am trying to make an R/C sumo bot for a competition. What would be the easiest way to run regular DC gearhead motors from a servo controller? I'm thinking of somehow converting the pwm signal into a digital signal that would run the motors forward or backward.
Topic by Stingray | last reply
Alright, so I took apart an old RC helicopter with a spy cam in it, and noticed it has 3 wires, just like a servo, so I modified an arduino script to keep a servo on all the time, and voila, the camera entered recording mode, now, I have an idea for something to do with this. I want to make a projectile for my air canon to fire the camera from, I think it might look pretty neat, however, I need a small simple circuit to make a PWM signal, and one that is constant enough to keep it recording constantly. I've seen some 555 timer ones but they fluctuate apparently, and I think that might turn the camera off then on.
Question by XOIIO | last reply
My power supply has a cooling fan inside. I wanted to slow it down to reduce the fan noise. When i use this circuit in the picture the PWM works great except for the low speed buzzing. Turns the fan into a speaker. Is there some way to eliminate the buzzing?
Question by WWC | last reply
Friend and I are very new to electronics and we were dimming LEDs in completely different ways I think. We both defended the way we had learned to do it without really knowing why :) Any thoughts? Also, with a servo, can you do both methods as well? And is there a way to tell a servo to go to a specific "spot" on its turning radius, or is it all relative, like supply a low voltage and it will turn a little? Do you just sort of calibrate it, so you can figure out how much voltage at how much time goes a constant radial turn? Blah
Question by prismspecs | last reply
I am in need of some way to change a PWM signal coming from my Arduino. The firmware only allows for PWM settings from 0-255. What I want to accomplish is this: With the 0 as the lowest value and 255 the highest for the incoming PWM signal I want to change it to a "smaller bandwidth". Ok, your are confused according to my crystal ball... The connected device (here a powerful laser) starts to work at PWM values of 6. The hardware limit is at around 180 as otherwise the tube will overpower and could be damaged. But I would like to be able to convert the full input signal to a range equal to being 6 the lowest and let's say 16 the highest. So the original 0 should, after the conversion, equal to 5, just be sure the laser is off. And the original 255 should equal to 16. It seems to be a quite simple task but either my brain does not work today or my friend Google does not like me anymore. I tried to search through the Marlin firmware but could not find anything simple and obvious to make thes changes directly in the firmware. So I need something that I can implement into the firmware or something I can put on a little UNO or so that sits between the big Arduino and the laser.
Question by Downunder35m | last reply
Hello, I've been breaking my head on this for a while now, and still couldn't find a correct solution for this. I want to be able to adjust the duty cycle (pulse width) with one potentiometer, and the frequency with another potentiometer, using a 555 timer. Adjusting the frequency shouldn't change the duty cycle! (which is the problem in All of the circuits I find online). This is an example of a circuit I find online, many of the circuits look just like this one (see picture) Now, the problem is that when you increase the resistance of the potentiometer for adjusting the frequency, that makes sure you can never get 0% or 100% duty cycle anymore! or not even close to that. It's because increasing that resistance, also decreases the 'discharging current' of the capacitor, so it will also increase the discharging time when that's not wanted. Without R2 it works perfectly, from 0% to 100% duty-cycle; but with the frequency potentiometer it all gets messed up. It's a little difficult to explain, I'll try it with another example :) To get 0% duty-cycle (or something close to that, like 10%), you'll need to make sure the path for Discharging the capacitor goes near 0Ohm. Increasing the potentiometer for the frequency makes that impossible because it's in series with the capacitor's charging and discharging circuit. So that would also increase the discharging time while I don't want that. When the resistance of the frequency potentiometer increases, the duty-cycle gets variable between just something like 45% and 55% (example) so that's not good. Is there any way do do this? :/ Thanks in advance, Elecotrials
Question by DELETED_Electorials | last reply
Hey guys gotta quick question: I need to be able to cut a PWM signal from a motor for a project. I'm currently using mechanical relays but I'm curious, will a solid state relay work? I know there are easier ways to do this but for right now I'm on a clock and I just want to know whether a SSR will work for cutting a PWM signal. Thanks guys!
Topic by HavocRC | last reply
I have an Hybrid Solar Inverter with 50A PWM solar charge controller inbuilt into it. It works on 24V battery bank. I am having 800Watt of PV module installed in the system. As my inverter is having PWM charge controller, I am not able to harvest maximum of power from panels. I want to know that, is there any arrangement or device which can be put in between PV panel and my Inverter which can increase efficiency or can act as PWM to MPPT converter for my Inverter? My Solar Pannels generates often 39V but I couldnt utilize the surplus power as it stepped down to 24 Volt.
Topic by Shashi BhushanS | last reply
How do I measure the maximum voltage reached by a very low duty cycle PWM signal without having to alter the signal. The multimeter shows no reading or gives a very brief wrong reading and falls back to zero. I don't have an oscilloscope. Are there any other alternative set-ups to measure just the voltage in this case. Please suggest.
Question by raftor | last reply
Question by Nr-Think different | last reply
IS 12V SUPPLY FOR PWM CONTOL INVERTER COMING TO THE I.C 7808 ,APART FROM TRANSFORMER, IS FROM OUTSIDE SOURCE & WHERE TO CONNECT IT'S NEGATIVE(OF OUTSIDE SUPPLY )?
Question by ER. ARJUN SHARMA | last reply
I'm working with a university and they love their Hobo's and I don't blame them... they're pretty straight forward to use... I'd like to write to the Hobo... here's the hobo analog inputs: 0 to 2.5 Vdc; 0 to 5 Vdc; 0 to 10 Vdc; 4-20 mA Hobo stats: http://www.onsetcomp.com/products/data-loggers/u12-006 Analog channels: 0 to 2.5 Vdc; 0 to 5 Vdc; 0 to 10 Vdc; 4-20 mA Accuracy (logger only): ± 2 mV ± 2.5% of absolute reading; ± 2 mV ± 1% of reading for logger-powered sensors Resolution: 0.6 mV Sample Rate: 1 second to 18 hours, user selectable Time accuracy: ± 1 minute per month at 25°C (77°F), see Plot A Operating range: -20 to 70°C (-4° to 158°F) Operating temperature: Logging: -20° to 70°C (-4° to 158°F) Launch/readout: 0° to 50°C (32° to 122°F), per USB specification Humidity range: 0 to 95% RH, non-condensing
Question by hydronics | last reply
I have 3sets of leds that conduct at 250v so I wanted to use my 100v TIP122 NPN(with TVS diodes to protect it from over voltage) and PC817 opto-isolator to PWM the LEDs which are common cathode, is there a way? Thank you all for all the superb suggestoins!
Question by yagoa | last reply
Hello I am wondering if there is someone who can help out a super beginner. I need to write a code that will allow me to type send a serial message to the micro (im using an arduino uno) to be able to set PWM port to a certain percentage thus changing the fade of an led. I would also like the program to echo back to me a text string indicating what has been done. Is there anyone who can help?
Topic by JonH23 | last reply
I have 5 - 12v LEDs running in parallel. Each lamp has it's own heat sink, fan and resistor,. Each one steadily uses about 850ma. I'm hoping to add a timer of sorts, something that adjusts the light level on a schedule. I've read about people using something like a 555 and/or the Arduino, but I'm kinda lost. Any pointers?
Question by lford4 | last reply
I've built a simple IR remote to trigger a led bar using... https://www.instructables.com/id/Control-your-Arduino-with-a-remote/step5/Control-stuff/ As my template. All the leds turn on a-okay but I'd like to be able to implement both an "off" function using the same button ie. button1=High leave on for desired period of time... button1=Low I'd like to be able to use a no delay fade in/out as well... ie. button7= All leds fade in/out until button7=low (using the method above^^) I've tried plugging in various other parts of code to no avail... Any help would be greatly appreciated!!! Thanks!
Question by vtrguy | last reply
I have dismantled a CRT monitor and I was wondering what I should with a UC3842B (HIGH PERFORMANCE CURRENT MODE PWM CONTROLLER) that was on the mains power side of the PCB.Here's a link to the datasheet for it.Any suggestions on what I should use it for and how to wire it up?
Topic by thermoelectric | last reply
A friend of mine and myself want to build a couple of small electric utility vehicles to use for chores around my farm and his cabin. We are thinking of something along the lines of the eMule. http://www.solarevolution.com/eMule/ We just bought 2 new 3HP 36VDC motors for a really great price off of eBay. See pics. I want to build some PWM controllers for these to help keep the price of the project down and because I like building things. I could use some help though on a few things. How many amps should the controller be rated for? 100 amps? Larger? Are there any designs out there for a DIYer like me? Thanks.
Topic by starguywisc
How do you match the duty cycle of the pwm to the color of the rgb led? since there are 256 possible shades per Color in an RGB light, there would be 256*256*256 possible combinations, but how would you know which color is which.....
Question by pacificace | last reply
This is no longer supported by electrocraft. I got it out of an old automated TIG welding positioner. If anyone knows anything about this particular one I'd be eternally grateful if you would share it with me.
Question by AngryGuy70 | last reply
I wanted to know if there are any flight controllers that have separate sensors. I want to use 2 either quad, hex or octo flight controllers with one setup as + and one setup as X to make an octocopter, duodecacopter or hexadecacopter ( 8, 12 and 16 blades respectively ). I want to have a a 6 or 9 DOF IMU connected to 2 separate controllers for larger multicopters. Either that or would anyone know how one might go about designing an arduino controller using either a pwm shield or a TLC5940. Thanks in advance
Question by monty324 | last reply
Hi all, I have been given a 24v DC 100W old scooter motor and one 12v battery (the other 12v battery died). I'd like to be able to control the speed of the motor and have been told I would need a PWM. I have found a PWM on ebay which says that it's a PWM HHO RC Controller, 12V 30A. Would this one be sufficient to slow the motor to say 10-20 RPM and back up to full speed? Thanks in advance.
Question by dchurch24 | last reply
I want to build a PWM but am having trouble finding transistors powerful enough. Will they act as one if I connect them in paralell?
Question by omnibot | last reply
Hi,I'm trying to figure out the way solar battery charger work and I'm a bit confused about the following point.I read that for batteries you could consider the PWM voltage to be equivalent to DC. This I understand well for average voltage (obviously it's the same), but what about the dynamics ?If your PWM frequency is something like 100 kHz, that's a 10 µs period. Does the battery has time to follow and make big voltage and current peaks or does it just averages all that to more decent values ?One way to put it is : Are the battery time constants indeed much bigger than the PWM period ?Thanks for any idea on that topic !
Topic by Emmanuel2015 | last reply
or a strip heater for bending plastic made from about 12 inches of heater element from an old toaster or hair dyer? do they use PWM,or just a big variable resitor?
Question by z28racer | last reply
I need to know where to put the POT in the treadmill motor controller? Because I have a digital controller from model MC2100 (proform 400X) Thanks
Question by dulo | last reply
Ok so im planning on building a portable coil/rail gun. But one issue is I cant quite find a circuit that would work best to drive a custom transformer. The charger I have now is a flyback driver that I used a wall adapter to power. I just need some advice and maybe schematics. Thanks, bud
Question by budhaztm | last reply
Hi ppl,I am currently making a variation on this circuit:http://www.edn.com/article/CA257052.htmlhttp://www.edn.com/contents/images/257052f1.pdfI understand how it all works but do not understand the principle of the inductor capacitor used (bottom left), if anyone could give a brief explanation of this (links are good too) and also some formulae i would b e very greatful!!thanks
Topic by drummer ian | last reply
The led driver http://www.parts-express.com/pedocs/manuals/073-048-parts-express-manual-7169.pdf Im using an arduino to fade LEDs through PWM. The code works on normal rgb LEDs, but i need it to be much brighter. I bought 3, 3 watt, HPLEDs. they are very very nice and bright. but only work with all colors full brightness... i have attached the arduino pins that controlled the normal rgb LEDs to the driver. but this does nothing different then if the pins were disconnected. also if i dont power up the driver and just plug in the arduino it will change the colors of the leds. but it will be just as bright as the normal ones because its only getting 5 volts instead of 13.5. also the color fade cycle acts really weird. not sure what thats all about or why it even does anything just with the arduino plugged in. Does anyone know where to get a decent LED driver? i have looked around for days and could not find what im looking for. this looked like my best option but its not working... thanks for your help. -Rex
Question by RexHex | last reply
Hi all, I hope everyone is well. I have 2 circuits here and was wondering if someone would show me how to connected them, it is probably very simple, but I just want to be sure. here are the 2 schematics I'll be working with... I assume I just use a common ground... but we all not what assuming makes us :) Thanks all in advance,
Topic by dalmond1
I have an electric billy cart with a dead controller board. I constructed the kit circuit below to replace the dead board and it works well enough for the job except for one small problem. The throttle on the billy cart utilizes a hall effect device and not a pot. The billy cart also has a handbrake with a switch that closes when applied. I use this with a resistor to discharge C2 and pull pin 4 (inhibit) high. This ensures a gentle start (as the capacitor slowly charges through the 100k resistor) if the brake is released with the throttle advanced. The output range of the throttle is 950 mV to 4.1 V if VREF (5V) is used as the supply. (I'm dropping it in in place of the pot.) 4.1 V is sufficient to achieve the maximum 90% duty cycle of the chip, but 950 mV leaves me with a minimum duty cycle of about 21%, and of course a motor that won't stop. Will changing the divider ratios 20k/2k2 & 47k/47k be sufficient to get me zero speed or am I going to have to do something more exotic? Thanks in advance.
Topic by Rasputin182 | last reply
Arduino comes with a simple program to make an LED fade on or off, however, as far as I can tell, the apparent brightness of the LED does not change linearly with the wpm duty cycle. After some research I found that this is because humans percieve brightness logarithmicly, not linearly. (Also, LEDs don't change brightness linearly with current, but sisnce I'm using PWM, i don't think that comes in to effect.) I found a simple look-up table to correct for this on this page. 255, 180, 128, 90, 64, 45, 32, 23, 16, 12, 8, 6, 4, 3, 2, 1,0 This seems to work very well, but I don't know where this comes from. Does anyong know the ectual equation to get the % duty cycle from the %brightness? I like to abstractise things.
Topic by Vick Jr | last reply
I want to control an LED strip from a microcontroller, ideally with parts I have on hand:- IRF740 MOSFET- PC123 Optocouple- ESP32 Microcontroller (Has 5V power regulator)- 12V LED strip (5m)A lot of the tutorials online seem to suggest that only a MOSFET are required (Except this one, which seems to me like a safer way of designing this, since I get to treat the 12V and 5V circuits as completely separate). I have a relatively limited knowledge of these things but it seems like sending the full current through the microcontroller on the ground side is a bad idea.Is it safe to run the LED strip's ground through the microcontroller? Are there any additional steps I should take to make sure I don't destroy my LEDs, MicroController, or anything else?
Question by jonrb
I have a Futaba RC transmitter and receiver, and an electric wheelchair. I want to be able to control the wheelchair via RC (a-la battlebots), and I do not want to control the joystick via servo. I also want to leave the wheelchair's joystick controls intact and either solder another RC device in tandem with the joystick, or hijack the control by having an external switch that switches from either manual joystick, or RC Freq. I have some experience in electronics, but only in the troubleshooting arena. I can fix things if they are broken and can troubleshoot to the board level, but have no experience building bots and have no RC experience. The solution needs to be low cost please. I can solder build boards from directions. I just have no "vision" of how to put these 2 systems together. I think the words "pwm to analog" have been thrown around online, but I need to know more. Please point me to websites, or send me instructions and Ideas. The wheelchair will not be a wheelchair forever. R2-D2, Wall-E, and an RC Lawnmower are all in contention. Thanks in advance.?
Question by CementTruck | last reply
Hi everyone, I have started working with my new Lilypad Arduino and some RGB leds. I have been loading code and testing 4 RGB leds (common anode) which I have set up in parallel across pins 11, 10, and 9. While powering the lilypad by usb the leds cycle through all colours (which is what I programmed it to do). Unfortunately, I have a problem when powering the lilypad by this power supply. When powered by the power supply the only colour that lights up is red (pin 11). Can anyone suggest anything?
Topic by Br3ntg33k
I am looking into making a laser tag system with an arduino and was wondering how easy it would be to make a laser diode output PWM signals, instead of using an infrared LED. I'm sure this has been considered before, but I couldn't find it anywhere!! Obviously all players would be given protective glasses to wear :) (on a side note: I was also wondering that if it was possible, could it be used in an RGB laser, to make more than seven colours?) Thanks in advance :)
Question by 5225jackiechanman | last reply
Let's say I want to vary the speed of the motor that operates at 12V. Since PWM on Arduino only provides the maximum current of 5V it can't power the motor sufficiently. So my question is how can I use PWM on Arduino to increase or decrease the input voltage of the external source? I will appreciate your answers.
Question by Shizen | last reply
I have a few motors (2) that i would need to be able to drive via a PWM input (Probably from pi/arduino). I have been looking at H bridges, and that seems to be my answer, however, I can't figure out which one i need... The motors are identical 9v ~2 amp stall current motors. I would need both directions for each, and would obviously be using an external power supply. With that said, which H bridge would suite my needs, along with what type of setup? I only have abut 4-6 PWM pins left to use, if that helps.
Question by RocketPenguin | last reply
Does anyone know any good PWM tutorials for the AtMega32 and AtMega168 chips. These are not arduinos. I am looking specifically for servo and DC Motor control but any tutorial on PWM should give me the base I need to move forward.
Question by TheTrustedOne | last reply