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Electronics => Electronics => Topic started by: hosa200 on March 16, 2014, 01:28:01 PM

Title: 48V DC motor relay or driver
Post by: hosa200 on March 16, 2014, 01:28:01 PM
Hello Every Body,

I have 48VDC motor (3A at load) ,I give it 48VDC from 4*12VDC batteries ,but i want to control it direction ,So I have tried relays but it burned out .

Can anyone help me to make a motor driver can handle 48VDC and 7A (for safe) to control motor direction and speed :) :)??

Thanks alot
Title: Re: 48V DC motor relay or driver
Post by: jwatte on March 16, 2014, 03:54:40 PM
Quote
So I have tried relays but it burned out

There exists relays/contactors that support > 7A loads and > 48V voltage. Try a better relay?
Title: Re: 48V DC motor relay or driver
Post by: hosa200 on March 16, 2014, 04:09:17 PM

There exists relays/contactors that support > 7A loads and > 48V voltage. Try a better relay?

i can't find a relay has more than 30VDC Maximum switching voltage
Title: Re: 48V DC motor relay or driver
Post by: jwatte on March 17, 2014, 10:11:48 AM
Power relays that do over 48VDC, up to 1000VDC, and 10+ A:
http://goo.gl/BtWbnP (http://goo.gl/BtWbnP)

Seems like $1.37 will get you there at 10A:
http://www.digikey.com/product-detail/en/G5LE-14%20DC12/Z1012-ND/280369 (http://www.digikey.com/product-detail/en/G5LE-14%20DC12/Z1012-ND/280369)
For a 16A current rating, you have to pay almost $3:
http://www.digikey.com/product-detail/en/G2RL-1A-E%20DC24/Z2845-ND/368854 (http://www.digikey.com/product-detail/en/G2RL-1A-E%20DC24/Z2845-ND/368854)

That being said, do you want speed control? If so, I'd suggest a MOSFET based motor controller. You'd probably have to go industrial-grade to power 48V motors, so expect to pay a few hundred in that case, and get ruggedized drivers.

Title: Re: 48V DC motor relay or driver
Post by: hosa200 on March 17, 2014, 12:09:22 PM

That being said, do you want speed control? If so, I'd suggest a MOSFET based motor controller. You'd probably have to go industrial-grade to power 48V motors, so expect to pay a few hundred in that case, and get ruggedized drivers.

thanks a lot,
about speed control ,i want to learn how to make my own driver
Title: Re: 48V DC motor relay or driver
Post by: jwatte on March 18, 2014, 12:08:36 PM
To make your own driver, you need four high-current high-voltage MOSFET transistors like the IRF530N, and two half-bridge drivers like the IRS2003. (Note: at least 100V GD rating for your application)
Then you need a PCB and connectors that can handle the current (which at 7A isn't a problem with 100 mil traces and 1oz copper -- if you can go 2 oz, so much the better!)
You also need a regulator that generates a 10-18V control voltage. 12V would be fine, and easy to make. Add a fast diode and a couple of 35V rated 100 nF ceramic capacitors per driver side, and you're done!

Title: Re: 48V DC motor relay or driver
Post by: hosa200 on March 19, 2014, 03:29:16 PM
To make your own driver, you need four high-current high-voltage MOSFET transistors like the IRF530N, and two half-bridge drivers like the IRS2003. (Note: at least 100V GD rating for your application)
Then you need a PCB and connectors that can handle the current (which at 7A isn't a problem with 100 mil traces and 1oz copper -- if you can go 2 oz, so much the better!)
You also need a regulator that generates a 10-18V control voltage. 12V would be fine, and easy to make. Add a fast diode and a couple of 35V rated 100 nF ceramic capacitors per driver side, and you're done!

Thank you,I'll try this.