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Electronics => Electronics => Topic started by: pos3idon on April 02, 2009, 08:33:31 PM

Title: Servo input voltage question
Post by: pos3idon on April 02, 2009, 08:33:31 PM

So I am working on my first project and I could use some advice.

I am using GWS servos which seem to require 6v input from my battery, however the batteries I have on hand are 9.6v so what is the best way to step down the voltage?  Should I use a regulator?  If so which one?

Thanks so much for the help :-)

Title: Re: Servo input voltage question
Post by: pomprocker on April 02, 2009, 11:15:42 PM

use an adjustable regulator with some resistors to give the servos their max allowable voltage.

Title: Re: Servo input voltage question
Post by: pos3idon on April 04, 2009, 12:40:47 PM

I'm just begining so do you think a product like this one would work for me?

http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=3735 (http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=3735)

I know the question is really basic but I'm working on a very tight build budget so I don't want to fry any components or end up with ones that wont work for me :-)

Thanks for the help

Title: Re: Servo input voltage question
Post by: ArcMan on April 04, 2009, 02:42:42 PM

That unit will work just fine.  Just make sure your total servo load doesn't exceed the 3A rating.

Title: Re: Servo input voltage question
Post by: pos3idon on April 04, 2009, 02:55:03 PM

one more question,  I just looking a little closer and it said that it would work with "2 to 5S Lipoly pack." Does this mean it will not work with NIMH or NICAD batteries within the specified voltage range?  I know the connectors will be wrong but I figure I can put on new ones.

Havn't worked with Lipoly batteries before so I'm a little confused thanks :-)

Title: Re: Servo input voltage question
Post by: SmAsH on April 04, 2009, 02:59:49 PM

nope most servos will work with any battery as long as it has the juice.

Title: Re: Servo input voltage question
Post by: ArcMan on April 05, 2009, 06:37:37 PM

Yea, they just give that spec for folks that don't realize that each LiPo cell is 3.7V.  It just means the input voltage range is 7.4V - 18.5V.

Title: Re: Servo input voltage question
Post by: SmAsH on April 06, 2009, 01:22:16 AM

Quote from: ArcMan on April 05, 2009, 06:37:37 PM

Yea, they just give that spec for folks that don't realize that each LiPo cell is 3.7V.  It just means the input voltage range is 7.4V - 18.5V.

servos can take 7.4-18.5V? i thought they had a limit of 7.2? or do these servos have some werid requirements?

Title: Re: Servo input voltage question
Post by: ArcMan on April 06, 2009, 01:02:48 PM

It's not a servo.  It's a BEC.

Title: Re: Servo input voltage question
Post by: Admin on May 07, 2009, 06:34:55 PM

You should buy new lower voltage batteries. A switching regulator can probably handle the current and not hurt you efficiency-wise, but I wouldn't recommend it.