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vigyanabikshu
07-11-2010, 06:11 PM
How can I drive(Both speed and direction) a dc motor that draws current 3 amps to 20 amps
I am currently using 2 relays, but not reliable
I think MOSFET H bridge is a solution.
Please help

Thanks in advance

vikas
07-11-2010, 06:19 PM
http://www.nex-robotics.com/products/motor-controllers/super-hercules-36v-30amp-motor-driver.html

vigyanabikshu
07-11-2010, 06:36 PM
Thank you for your quick reply Vikas.
I checked the page, but the cost is too much
Super Hercules 36V, 30Amp Motor Driver
Product ID: NR-MDR-S-HER-36V30A
Weight: 110 gms
Price: Rs.2,576.25
Is there any schematic ?

Actually I have developed a working prototype of remote controlled coconut tree harvesting robot. It consists of 8 DC motors
Currently I am using Relays to drive these motors, but they are not reliable

Thanks

vikas
07-11-2010, 07:34 PM
Then stick with relays ,Mosfets based solution will get expensive . B

I can suggest something if you give more details like motor connection circuit, motor types .

Photos would be nice tooo ...

MohitM
07-11-2010, 07:43 PM
Do a search on "H bridge Mosfet" and you should be good.

Check this out:
http://www.onegentleman.biz/Hardware%20Design/Original%20H%20Bridge/First%20H%20Bridge.html

Whatever Mosfets you use, ensure that the Rds value is below 50 milliohm if you are pushing upwards of 10A. IRF4905 and IRF3205 are good and available in India.

MohitM
07-11-2010, 07:45 PM
Mosfets aren't too expensive these days. The p/n channel pair I noted above should be Rs. 80-100/pair depending on where you are. A 20A relay isn't going to be cheap either.

vigyanabikshu
07-11-2010, 08:29 PM
Thank you very much Mohit Mahajan for your valuable information. I will try the circuit tomorrow.

vigyanabikshu
07-11-2010, 08:35 PM
Then stick with relays ,Mosfets based solution will get expensive . B

I can suggest something if you give more details like motor connection circuit, motor types .

Photos would be nice tooo ...

Hi Vikas,
But I have to drive 8 motors in the robot. Rs.2,576.25 per each motor costs Rs.20,610.00!!!!!!!!!!!
I am using a 12VDC wiper motor like below
http://www.scary-terry.com/rockchair/pwipermotor.jpg

vikas
07-11-2010, 09:25 PM
From net i found

http://www.alibaba.com/product-gs/212459255/12V_Wiper_Motor.html

It is no where near 20 A but like 4A / 8 A stall current and 1.2 - 3 A running current.

So i think the famous 5 A Hbrdige would do fine, Use two in parallel per motor if required.

http://www.ikalogic.com/h_bridge.php

Constructing the above h-bridge should be About Max Rs 100 / bridge .

vigyanabikshu
07-11-2010, 09:36 PM
Thank you very much Vikas
The schematic is simple and I will try it also

allbits
07-11-2010, 11:03 PM
It will be a good idea to measure the motor currents before you buy the controller. Motors can draw upto 5 times their rated currents at load, during turn off and turn on. Things get very complicated when you have a PWM driving them.

speed control for anything above 5A will be expensive, if you buy it. things are far cheaper if you DIY, but at the cost of chance of failure.

asimov_18
07-12-2010, 03:45 PM
Hi,
Use T-bridges and then u can use solid state relay as well or mosfet like IRFZ44N

Asimov

vigyanabikshu
07-23-2010, 05:42 PM
I tested the MOSFET H-BRIDGE motor driver board that can drive 12 to 50 Volt DC motor up to 30Amps successfully
I used HIP4082 to drive mosfets and this is the best method. No any transistor/Logic ICs are required.
It costs just Rs.75/-
Feel free to contact me for more info

docel
07-23-2010, 11:26 PM
I tested the MOSFET H-BRIDGE motor driver board that can drive 12 to 50 Volt DC motor up to 30Amps successfully
I used HIP4082 to drive mosfets and this is the best method. No any transistor/Logic ICs are required.
It costs just Rs.75/-
Feel free to contact me for more info

After generating 13 posts in your thread, it would be a gentelman's gesture to share the details in the open Forum instead of soliciting personal contacts. That way, the members who posted replies to you would feel nice for spending their time and appreciate your gratitude.

Good Luck :)

vigyanabikshu
07-23-2010, 11:53 PM
It has taken 1 week hard work to make this success

Below is the schematic

257

vigyanabikshu
07-31-2011, 08:48 PM
Another more simple low cost dc motor control circuit with speed and direction control found at
http://www.picbasic.co.uk/forum/showthread.php?t=8567&page=1

vigyanabikshu
07-31-2011, 08:49 PM
It uses one relay and one mosfet only
"http://www.picbasic.co.uk/forum/attachment.php?attachmentid=2517&d=1208532602"

emokid
10-05-2012, 03:26 AM
hey there,
I was looking at your circuit and, was wondering if it was possible to use a single pwm input instead of the pic to control the driver?