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sudarshan
06-24-2012, 12:10 AM
Hi guys
I need a small help.

i have a relay based motor driver. something similiar to this
http://www.instructables.com/id/Super-Easy-Reversible-Motor-Control-for-Arduino-/step2/Schematic-and-Theory-of-Operation/

but my need is i need to drive motor rating = >10 amps so can anyone help me choose the right components for the job.

i will be using pwm from microcontroller say 2khz to the enable pin so i can control the speed.




Thank you in advance

allbits
06-24-2012, 08:17 AM
Hi guys
I need a small help.

i have a relay based motor driver. something similiar to this
http://www.instructables.com/id/Super-Easy-Reversible-Motor-Control-for-Arduino-/step2/Schematic-and-Theory-of-Operation/

but my need is i need to drive motor rating = >10 amps so can anyone help me choose the right components for the job.

i will be using pwm from microcontroller say 2khz to the enable pin so i can control the speed.




Thank you in advance


Dont use relays with PWM. Relays can damaged, especially at 2Khz PWM speeds AND especially at 10A.
Use MOSFETS. for 10A, use a MOSFET driver like IR2110 along with 20 - 40A MOSFETs, make an H bridge, and drive !

And also check the motor specifications, to know the best PWM frequency for the motor.

sudarshan
06-24-2012, 05:24 PM
I am not telling about pwm to relay.
i am in need of a circuit which can drive pwm from controller. consider a mosfet (in the link they use TIP transitor) which control the voltage with pwm.
what i mean to say is if a use a relay and 1 mosfet i can reduce the use of 3 more mosfet in a build a h bridge and also h bridge needs 2 pwm channels so i can reduce it to 1. and only one heat sink is needed.

IR2110 says it can drive only 2A i need for => 10 Amps. what do you think about 2n3055 ?

allbits
06-25-2012, 07:58 PM
I am not telling about pwm to relay.
i am in need of a circuit which can drive pwm from controller. consider a mosfet (in the link they use TIP transitor) which control the voltage with pwm.
what i mean to say is if a use a relay and 1 mosfet i can reduce the use of 3 more mosfet in a build a h bridge and also h bridge needs 2 pwm channels so i can reduce it to 1. and only one heat sink is needed.

IR2110 says it can drive only 2A i need for => 10 Amps. what do you think about 2n3055 ?



Dear Sudarsan,
I did not get what you said, but i assume, that you know what to do, from what you said. Anyway, i still dont understand how you will be able to change directions with one MOSFET and a relay. So i am not in a positions to comment on that.

IR2110 is not a motor driver, it is a MOSFET driver,as would have clearly written in the datasheet. That is why i asked you to use it WITH MOSFETS of necessary ratings. So try to understand what I have written, read two or three times if you cannot understand.

And I think of 2N3055 as a very good chap. we went to high school together.

sudarshan
06-25-2012, 10:19 PM
i am really sorry i didnt make my point clear at all.

see this diagram
http://www.circuitstoday.com/wp-content/uploads/2011/02/dc-motor-controller.png

just forget the 555 section as i will be using a microcontroller. what i want to know is a very good replacement for BD139 in the diagram.
which is definetly a mosfet. what i need to know is which mosfet will suit for best results ie high current, pwm upto 20khz, and all other factors. i am asking you guys because some of you must have already used or tested the best.

thank you

lolman_returns
06-26-2012, 07:29 PM
I think this is what you are looking for,
http://www.spaennare.se/pwm.html#chap7

This chapter goes very detailed on the reasoning part and has some good circuits. I have used the circuits with great results.

sudarshan
06-26-2012, 07:43 PM
Thank you very much thats what i have been looking for