Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: joejcoolest on July 04, 2009, 02:14:13 PM

Title: how do I wire a motor with 4 leads?
Post by: joejcoolest on July 04, 2009, 02:14:13 PM

I've been working on making an electric skateboard for the past few months, and I finally got most of my components together. My problem is that the motor I bought has four wires: 2 red and 2 black. More information on the motor can be found at the manufacturer's website: http://www.npcrobotics.com/products/viewprod.asp?prod=37&cat=20&mode=txt (http://www.npcrobotics.com/products/viewprod.asp?prod=37&cat=20&mode=txt)

Its a DC 24V motor. Apparently its "4 pole; one wire lead per brush."

So far I've tried hooking up one pair of red and black wires, and that does make the motor run. Is it running at half capacity when I use only one pair of wires? What I want to try to do next is basically splice the two red wires together and then the two black wires together so that I'll have one pair of wires. But then why wouldn't the manufacturer have done that already? Why does this motor have four wires..? 

I wanted to get some more information so that I don't risk damaging my motor.

Other information about my setup: I'm using four 12 volt batteries, wired up to 24 volts. I don't want to use any type of motor controller if I can get away with it. Eventually I might add a relay or a mosfet for safety so that the user doesn't have 24 volts at 40 amps near his hand. Any tips or insights would be greatly appreciated.

Title: Re: how do I wire a motor with 4 leads?
Post by: Soeren on July 05, 2009, 01:44:38 AM

Hi,

Quote from: joejcoolest on July 04, 2009, 02:14:13 PM

I wanted to get some more information so that I don't risk damaging my motor.

Why ask here when you really should be sending an email to NPC Robotics?

Title: Re: how do I wire a motor with 4 leads?
Post by: MangoBot on July 05, 2009, 04:42:50 PM

You could set up seperate batteries for each red-black pair

Title: Re: how do I wire a motor with 4 leads?
Post by: jamort on July 06, 2009, 02:19:08 AM

what the wires are probably for are two positive and two negative so you can plug one battery on it and another one too

Title: Re: how do I wire a motor with 4 leads?
Post by: SmAsH on July 06, 2009, 02:25:23 AM

have you tested the resistance between all the wires?
this could lead to something...

Title: Re: how do I wire a motor with 4 leads?
Post by: joejcoolest on July 07, 2009, 01:41:50 PM

Thanks a lot for all your help! I contacted NPC and I thought I'd post their response in case anyone else has the same problem.

"Attach both red wires from the motor to one side of your controllers output, connect the 2 black wires to the other output.
NPC wired the brushes individually to handle larger current loads."

So I think my idea to connect the wires together to make one red wire and one black wire was on the right track. That still doesn't quite answer if I can safely run the motor with only one pair of wires to get a half-power mode, but my guess is that its not really designed to do that. Hopefully my other wires will hold up since the rest of my setup uses wires that aren't as thick as the motor's leads.

Hopefully I'll get my skateboard working and I can make a post about my success.  :)