Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: BANE on April 16, 2011, 09:31:26 AM

Title: Motor Wiring with Motor controller?
Post by: BANE on April 16, 2011, 09:31:26 AM
Hello all,
I just want to get some advice on the best way to wire motors.  To help explain Ive sketched out two images (sorry for chicken scratch).  Basically i have four wheel chair motors 24v on a robot that use differential steering (two motors per side) and a total of four 12v 33ah lead acid batteries.  My current set up is the first image where i have two sabertooth2x25 driving a motors per channel.  However, under heavy load the motor controllers still brown out occasionally.  As of yesterday, i purchased a 2x50HV motor controller in hoping to take care of the browning out issue. 

This 2x50HV has the capabilities of 48v so i want to wire by battery array for this and power my motors as seen in the second image.  Does anybody see any potential issues in doing this?
as always, any comments are appreciated, 
Title: Re: Motor Wiring with Motor controller?
Post by: waltr on April 16, 2011, 10:01:41 AM
What wire are you using from the batteries to the motor controller? The wire should be fairly heavy gauge and direct to reduce voltage drop due to RI^2 losses.

The one advantage of a higher voltage is the current can be lower. Can your motors run at the higher voltage without over heating?
Title: Re: Motor Wiring with Motor controller?
Post by: BANE on April 16, 2011, 10:17:31 AM
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What wire are you using from the batteries to the motor controller?
my current setup uses 10gauge, but if i use the 48v set up I get some 8gauge

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The one advantage of a higher voltage is the current can be lower.
thats exactly my logic,
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Can your motors run at the higher voltage without over heating?
the motors are rated at 24v and after a battery charge get about 28v max but i would dare to go anywhere near 48v with them.  thats why i would have them wired in series so they still only get 24v.  Also, the motors get fairly hot with 24v after a go bit of use

btw, thanks for the response