Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: superchiku on March 04, 2008, 11:44:01 AM

Title: power supply problem for 12 v motor
Post by: superchiku on March 04, 2008, 11:44:01 AM
hey ppl my problem is that i have got 2 12 v motors with 300 mA draw iam using l293d for motor control but iaam in a fix what kind of power supply to use i used 2 9 v battery in series and regulated it at 12v using an IC but the motors draw too much power so i gave it up so can u ppl help me by telling what kinda power supply i should use for the motors and also if i use ac and step it dow to 12v and then use bridge rectfier then can u plzz give the circuit

any kinda help is much appreciated
Title: Re: power supply problem for 12 v motor
Post by: benji on March 04, 2008, 04:41:53 PM
do you mean your batteries are goin empty in a short time? buy a rechargable one
as in robots its not a good idea to rectify ac as you always have to connect it to your bot by a wire...
Title: Re: power supply problem for 12 v motor
Post by: ed1380 on March 04, 2008, 05:20:00 PM
some lead acid batterys. or 2 6v nimh in series.
Title: Re: power supply problem for 12 v motor
Post by: subcaptain on March 04, 2008, 05:40:47 PM
go to towerhobbies.com. Lots of battery choices. Most chargers for NiCd or NiMh won't charge to 12 volts, so what I do is wire two 6 volt packs in series but only charge one pack at a time. LiPoly is another choice. If you are going to do robotics you need to become familiar with RC airplane and car batteries. Good luck.
Title: Re: power supply problem for 12 v motor
Post by: superchiku on March 04, 2008, 09:35:47 PM
i know non rechargable batteries are not a good idea but still rechargable batteries cost a lot and take lot of time to charge up time which i cannot afford so thats why  i decided to go with normal batteries and also nimh or nickel cadmimum batteries are not available here so thats the major problem
Title: Re: power supply problem for 12 v motor
Post by: ed1380 on March 04, 2008, 09:50:26 PM
if nicd or nimh arent available then what is? only thing i can think of is lantern batteries
Title: Re: power supply problem for 12 v motor
Post by: superchiku on March 04, 2008, 10:01:33 PM
ya lantern batteries but they are heavy and bulky now thats another problem nicd and nimh battery packs are costly and out of my budget iam really stuck plzz help
Title: Re: power supply problem for 12 v motor
Post by: paulstreats on March 05, 2008, 02:28:52 AM
maybe you can get some rechargeable nimh aa cell batteries like these http://www.mdsbattery.com/shop/productprofile.asp?shop=us&ProductGroupID=1125&Brand=&DepartmentName=&DepartmentID= (http://www.mdsbattery.com/shop/productprofile.asp?shop=us&ProductGroupID=1125&Brand=&DepartmentName=&DepartmentID=)
Title: Re: power supply problem for 12 v motor
Post by: Admin on March 15, 2008, 05:23:34 PM
actually, rechargeable batteries are cheaper than non-rechargeable . . .

not just in terms of mAh/$, but also since you do not need to constantly replace them . . .