Hi guys!
I am creating musical fountain with arduino duemilonove. I want to drive DC motor with arduino, only thing i need to control is speed.
The motor i am using is here http://www.mabuchi-motor.co.jp/cgi-bin/catalog/e_catalog.cgi?CAT_ID=rs_360sh
To run motor i chose this scheme from youtube tutorial http://aksoapy29.comoj.com/diagram2.png
Well i have few problems, i tried this scheme without arduino, using 2 batteries that output 3V. 3V on transistors base and 3v on motor(as it is in the picture). I thought that maybe i should use higher voltage on motor, i bought 9V battery. Before i tried connecting my 3v battery directly to motor and motor worked, now i tried connecting 9V battery to the motor and it does not work.... Can u explain why it is that way? Why transistor may not work and is this scheme adequate at all? That video is here: http://www.youtube.com/watch?v=hcpqt-BREqI&feature=related
I would be really thankful for fast replys as it is my bachelors work and i am a bit low on time. Yes i know since i study in university i should know more, i forgot a lot of things that we learned since never practiced them, but well it comes back slowly:D
UPDATE: Transistor is 2n2222 Small Bio

[quote=William post_id=213 time=1488371722 user_id=64] Hi guys!
I am creating musical fountain with arduino duemilonove. I want to drive DC motor with arduino, only thing i need to control is speed.
The motor i am using is here http://www.mabuchi-motor.co.jp/cgi-bin/catalog/e_catalog.cgi?CAT_ID=rs_360sh
To run motor i chose this scheme from youtube tutorial http://aksoapy29.comoj.com/diagram2.png
Well i have few problems, i tried this scheme without arduino, using 2 batteries that output 3V. 3V on transistors base and 3v on motor(as it is in the picture). I thought that maybe i should use higher voltage on motor, i bought 9V battery. Before i tried connecting my 3v battery directly to motor and motor worked, now i tried connecting 9V battery to the motor and it does not work.... Can u explain why it is that way? Why transistor may not work and is this scheme adequate at all? That video is here: http://www.youtube.com/watch?v=hcpqt-BREqI&feature=related
I would be really thankful for fast replys as it is my bachelors work and i am a bit low on time. Yes i know since i study in university i should know more, i forgot a lot of things that we learned since never practiced them, but well it comes back slowly:D
UPDATE: Transistor is 2n2222 [/quote] 1. What value resistor are you using between the Arduino pin and the transistor base? The diagram shows 1K, which is only suitable for very small motors. 100 to 180 ohms would be better (do not go below 100 ohms).

2. The stall current of that motor (assuming you are using the -2885 variant) is 8.6A which is much higher than a 2N2222 can switch. Use a mosfet to switch it instead of the 2N2222.

3. A standard 9v battery is intended for low current applications and is not capable of supplying enough current for that motor. Comment Bio

[quote=Junaid_Shahid post_id=214 time=1488371756 user_id=48] [quote=William post_id=213 time=1488371722 user_id=64] Hi guys!
I am creating musical fountain with arduino duemilonove. I want to drive DC motor with arduino, only thing i need to control is speed.
The motor i am using is here http://www.mabuchi-motor.co.jp/cgi-bin/catalog/e_catalog.cgi?CAT_ID=rs_360sh
To run motor i chose this scheme from youtube tutorial http://aksoapy29.comoj.com/diagram2.png
Well i have few problems, i tried this scheme without arduino, using 2 batteries that output 3V. 3V on transistors base and 3v on motor(as it is in the picture). I thought that maybe i should use higher voltage on motor, i bought 9V battery. Before i tried connecting my 3v battery directly to motor and motor worked, now i tried connecting 9V battery to the motor and it does not work.... Can u explain why it is that way? Why transistor may not work and is this scheme adequate at all? That video is here: http://www.youtube.com/watch?v=hcpqt-BREqI&feature=related
I would be really thankful for fast replys as it is my bachelors work and i am a bit low on time. Yes i know since i study in university i should know more, i forgot a lot of things that we learned since never practiced them, but well it comes back slowly:D
UPDATE: Transistor is 2n2222 [/quote] 1. What value resistor are you using between the Arduino pin and the transistor base? The diagram shows 1K, which is only suitable for very small motors. 100 to 180 ohms would be better (do not go below 100 ohms).

2. The stall current of that motor (assuming you are using the -2885 variant) is 8.6A which is much higher than a 2N2222 can switch. Use a mosfet to switch it instead of the 2N2222.

3. A standard 9v battery is intended for low current applications and is not capable of supplying enough current for that motor. [/quote] Thank you very much for your reply!
About stall current...it should still work with 2n2222 if there is no load? Or is stall current needed to start the engine?
I will write what results i got...
Tried to search for mosfet in local shops.... it seems harder than i thought.. could u suggest me some models that u know that are cheap enough? I cant put more money than 10 euros in that. If there is none, maybe some different scheme?
What about using thyristor? Comment Bio

[quote=William post_id=215 time=1488371805 user_id=64] [quote=Junaid_Shahid post_id=214 time=1488371756 user_id=48] [quote=William post_id=213 time=1488371722 user_id=64] Hi guys!
I am creating musical fountain with arduino duemilonove. I want to drive DC motor with arduino, only thing i need to control is speed.
The motor i am using is here http://www.mabuchi-motor.co.jp/cgi-bin/catalog/e_catalog.cgi?CAT_ID=rs_360sh
To run motor i chose this scheme from youtube tutorial http://aksoapy29.comoj.com/diagram2.png
Well i have few problems, i tried this scheme without arduino, using 2 batteries that output 3V. 3V on transistors base and 3v on motor(as it is in the picture). I thought that maybe i should use higher voltage on motor, i bought 9V battery. Before i tried connecting my 3v battery directly to motor and motor worked, now i tried connecting 9V battery to the motor and it does not work.... Can u explain why it is that way? Why transistor may not work and is this scheme adequate at all? That video is here: http://www.youtube.com/watch?v=hcpqt-BREqI&feature=related
I would be really thankful for fast replys as it is my bachelors work and i am a bit low on time. Yes i know since i study in university i should know more, i forgot a lot of things that we learned since never practiced them, but well it comes back slowly:D
UPDATE: Transistor is 2n2222 [/quote] 1. What value resistor are you using between the Arduino pin and the transistor base? The diagram shows 1K, which is only suitable for very small motors. 100 to 180 ohms would be better (do not go below 100 ohms).

2. The stall current of that motor (assuming you are using the -2885 variant) is 8.6A which is much higher than a 2N2222 can switch. Use a mosfet to switch it instead of the 2N2222.

3. A standard 9v battery is intended for low current applications and is not capable of supplying enough current for that motor. [/quote] Thank you very much for your reply!
About stall current...it should still work with 2n2222 if there is no load? Or is stall current needed to start the engine?
I will write what results i got...
Tried to search for mosfet in local shops.... it seems harder than i thought.. could u suggest me some models that u know that are cheap enough? I cant put more money than 10 euros in that. If there is none, maybe some different scheme?
What about using thyristor? [/quote] It is hard to find mosfets in local shops, and those that you do find are typically not suitable for logic level gate drive (i.e. 5V, not 10V). It's better to buy them online, for example from Farnell/Element14, RS or Rapid Online. Here are some suitable part numbers:

STP40NF10L
STP40NF03L
IRLZ24PBF
IRL3303PBF

Avoid IRL540, it's one of the more commonly available mosfets but not suitable for driving directly from an Arduino because it needs 10V gate drive.

Thyristors are not good for switching DC because once turned on, they stay on until the current through them drops to near zero.

I wouldn't continue with the 2N2222, if the base resistor is too high then it won't pass enough current, and if it is low enough to pass the running current then you will exceed its current rating when the motor is starting up or stalled. Let check: [url=http://www.theengineeringprojects.com/2016/03/motor-speed-control-using-arduino-proteus.html]DC MOTOR SPEED CONTROL USING ARDUINO[/url] Comment Bio