DC motor consume to much current

[lucaswilliam7868]

Hello , i was creating a project where i was gonna control DC motor speed using Arduino PWM, , while using a max 100mA of current from my 3,7 volt battery, while the DC motor have internal resistance of 3 ohms, but it wont Turn on if i but any resistors to limit the current to 100mA, should i buy a different DC motor or Something else is the problem?

[hammy]

Circuit diagram ?
Motor spec ?
Motor controller ?
Code ?

3.7/3 =~ 1amp

[jhaine]

Hopefully you aren't running the Arduino from the battery? As hammy points out, the start current of the motor is over 1 amp but when it's running it will be much less. What type of battery is it? 3.7v could be a coin cell or a big LiPo cell, no chance of a motor running in the first! You don't want to put any series resistor in, but make sure the supply can manage the start current of the motor. And supply the details he mentions.

[lucaswilliam7868]

just 3.7 volt 2000 mAh rechargable battery conected to dc motor

[lucaswilliam7868]

the arduino is powered by my laptop, just 3.7 volt 2000 mAh rechargable battery conected to dc motor

[hallowed31]

@lucaswilliam7868

while using a max 100mA of current from my 3,7 volt battery

Why is this especially important? The spec mAh on a battery is just how much juice is in the tank, not it's ability to "deliver" current (which isn't how it works anyway).

[TomGeorge]

Hi, @lucaswilliam7868
Can you please post a copy of your circuit, in CAD or a picture of a hand drawn circuit in jpg, png?
Hand drawn and photographed is perfectly acceptable.
Please include ALL hardware, component names and pin labels.

Can you please post some images of your project so we can see your hardware?

Can the Lipo battery run the motor directly connected to their leads with no controller involved?

Do you have a DMM?

Thanks.. Tom...

[johnerrington]

How to make a schematic you can post.

When you submit a question on the forum you will usually need to add a schematic (circuit diagram). The tutorial that follows will explain some ways to create a useful image; however lets start by explaining how to add the image to your post. Its easy. Having created the image all you need to do is : Save the image somewhere convenient - maybe your desktop Start your post, and place the cursor (insertion point) where you want the image to be shown; [upload image to forum] 3: click th…

[lucaswilliam7868]

controlling motor speed using Arduino PMW.pdf (4.8 KB)
, in tinkercad it works but in real life motor only responds to 255 PWM not any lower

[TomGeorge]

Hi,
Please post your schematics as EXPORTED jpg or png and post the image into the thread.
@lucaswilliam7868 schematic.

Can you please post an image(s) of your project?
What is the BJT, T1.
Can your Lipo run the motor directly?

Please post your code.
To add code please click this link;

How to get the best out of this forum

See also FAQ - Arduino Forum for general rules on forum behaviour and etiquette. Hello, Welcome to the Arduino Forum. This guide explains how to get the best out of this forum. Please read and follow the instructions below. Being new here you might think this is having rules for the sake of rules, but that is not the case. If you don’t follow the guidelines all that happens is there is a long exchange of posts while we try to get you to tell us what we need in order to help you, which is fru…

Thanks.. Tom...

[johnerrington]

R1 limits Ib to about 4mA.
Your motor "wants" about 1000mA.
So you need a transistor with an HFE (not Hfe) of 1000/4 = 250.

There is no such beast.

Change your circuit to use a mosfet - like this

skillbank: Experiments and projects with an Arduino microcontroller

as shown you will also need to add a protection diode across the motor.