I have seen this on google and want to know if that will really work for the dc motor i really don't want to use 2 power sourse one for arduino and one for the dc I just want 1 usb cable to power every thing is that possible with the relay ? with the arduino nano
That may not even be possible.
Standard computer USB ports are not intended to power motors, and you can severely damage a computer in trying, especially motors labeled "AC/DC", like on the drawing you found and posted.
For advice on how to get help on this forum, have a look at the "How to get the best out of this forum" post, linked at the head of every forum category.
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MCUs and MPUs have current measured in a few thousandths of an amp, motors use multiple amps. That is at least a 1,000x difference. IOW, it will not work.
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What do you recommend power source to power up the arduino and the motor at the same time ? do you have any idea other than using 2 power sources ? ( Note i am using 3v-5v water pump Dc motor )
Do you a datasheet for the pump or a link to the website where you purchased it?
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This might help:
Gil's Crispy Critter Rules for Processor Hardware:
- Rule #1: An Arduino is NOT a Power Supply!
- Rule #2: Never connect anything inductive (motors, speakers) directly to an Arduino!
- Rule #3: Avoid connecting or disconnecting wires while the power is on.
- Rule #4: Do not apply power to any pin unless you are certain of what you're doing.
- Rule #5: Do not exceed the maximum voltage ratings.
- Rule #6: Many Arduinos cannot power transmitters directly.
- Rule #7: Before powering your project, take a break and double-check the wiring.
LaryD’s Corollaries:
- Coro #1: When starting out, add a 220Ω resistor in series with both input and output pins to protect against shorts.
- Coro #2: Invest in a Digital Multi-Meter (DMM) to measure voltages, currents, and resistance.
Note: Violating these rules can turn your Arduinos into crispy critters. For optimal performance, keep your wires under 25 cm (10 inches).
Additional Tips:
- The L293 motor driver, though common, is inefficient as it can lose around 3V as heat when driving both legs of a motor. Consider using a motor driver with MOSFET outputs to reduce heat loss and conserve battery power.
- For more on powering Arduino boards, explore this guide: Powering Alternatives for Arduino Boards.
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You will only program the Arduino with the USB cable.
To power your project with one power source, use a DC power supply large enough to run your DC motors (if your motor is A/C, nothing I write applies). The power supply will be directly connected to the COM of the relay.
The power supply will also be connected to a buck converter to supply the Arduino with greater than 7.5vdc to the VIN pin. The other components in your drawing can use the VCC power from the Arduino.
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so what i understand that
- USB just for the programming
- if I want the ardunio works for long run i will need an external power supply
what I am thinking right now is to get 3.7v rechargable battery to power the arduino by the VIN port and use at as will for the raley COM to power the DC motor and and If I am using more than 7.5V battery I will need to wire it with buck converter
- Question: If what i mintioned above will work, Would me a good idea to add to the battery the TP4056 3.7V to charge it ? ( i read that charnging the battery while it is active will harm the circuit is that true ? )
Mini Submersible Water Pump Technical Specifications:
- Working Voltage: DC 2.5V-6V
- Working Current: 130-220mA(Strain Current)
- Power Consumption: 0.4-1.5W
- Flow Rate: 80-120L/H
- Material: Plastic
- Inlet diameter: 4.7mm
- Outlet diameter: 7.5mm
- Working Life: 500 hours
- Waterproof: IP68
- Cable Length: 20 cm
- Color: White
- Max. Water Pumping Distance: 110 cm
- Dimension: 45 (L) x24 (W) x33 (H) mm
No. Arduino VIN pin needs more than 7.5vdc, less than 12vdc.
The "COM" part of the Relay is where you connect +power from the power supply.
The "N.O." part of the Relay is where you connect the +power from the pump.
When you enable the Relay, the +power from the power supply will be shorted to the +power of the pump.
Connect all GROUND potentials.
No. Are you making a pump work, or Stone Soup? Follow through with the pump idea before imagining what you will need for a icecream maker on a spacecraft.
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I worked with relay from before it is just i didn't work on a project that i am planning to use for a long time, I just want to build somthing to water my plants when i am away for weeks to months from home lol
so mostly I will use multiple from the 3.7 battery or just the 9v battery I have already built everything but i have problems in the wiring the power thing not for just this for other projects as well
thanks alot for the help
I would consider placing a .1 uF or 100 nF non polarized cap across your pump motor power.
Next, just about all micro-controllers have an intense dislike of motor noise. They tend to do random resets and other weird things. This is why a seperate power supply for motors is commonly suggested.
Forget a 9 volt PP3 battery unless you plan to be home and you don't. You will be forever replacing your battery.
Ron
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I noticed the noise for sure xd
and yeah that's why I was trying to make it work with just the USB, my only way is rechargeable battery correct ?
Yes, you can run on a rechargeable battery. While LiPo is all the rage personally I would likely just use a 12 volt SLA (Sealed Lead Acid) battery and leave a battery tender on it. I am located in NE Ohio USA where we get cold winters. During the winters I leave my motorcycle out in the garage on one of these from Amazon
They maintain the battery and your light load on it will not effect it. They are inexpensive and work just fine, you never lose power. Next I would just add two inexpensive buck converters. The buck converters can be as simple or complex as you want, some include In and Out voltage and current monitoring displays. Again Amazon choose one. The cheap ones work fine. Most will deliver as much as 2.0 amps or more.
That is how I would likely approach it. Just my thoughts. There are plenty of ways.
Ron
Get a big beefy power bank with 2 usb output ports. Use usb cable to power your arduino and another for your pump (strip the pump cable end and use red +5V and black GND).
Why would you want to use a rechargable battery. If it goes dead while you are away, your plants won't get watered. Why not use a plugin wall adaptor?
Charging a li-ion battery while it is in use is never a good idea.
I am still learning more about electricity parts I really don't want to play with the 220V until I am am 100% sure about what I am doing XD but thats not bad idea as well I will just need AC to Dc converter I guess
I don't want you to either, that why we use power supplies and plugin wall adaptors, to reduce the 220V to 5V or 9V etc.
Do you know how to solder and use a protoboard.