parallax small servo mA usage?

trend

I·am using·a parallax standard servo:
http://www.parallax.com/detail.asp?product_id=900-00005

I cannot find anywhere in the documents how many mA this servo requires.. Do you'll have any idea what the max is?
Also, what voltage/mA is required on the signal line? (I am trying to calculate the guage wire I can use)

thanks guys! Lee

·

Ken Gracey

Lee,

This is equivalent to a Futaba S-148 servo. 6V and 110 mA standard current draw with about 150 mA or higher under load. The servo works best with a 5V supply.

22, 24 gauge wire is fine. In fact, for a good "engineering analysis" just look at the wire used by the servo manufacturer. It looks and feels a bit smaller than 24 gauge wire. I'm not an engineer, but I know I wouldn't waste any of our engineer's time calculating the appropriate wire gauge for a servo.

Ken Gracey
Parallax, Inc.

trend

Great, that is what I used (24gauge shielded)

Urhm, please don't take this the wrong way, I am just curious, why isn't the mA rating in the datasheet?
http://www.parallax.com/dl/docs/prod/motors/stdservo.pdf
or
http://www.parallax.com/dl/docs/books/edu/roboticsservomod.pdf

Is it because you'll change brands of servos from time to time?

Like I said, I am just curious.

Keep up the great work guys! (by the way, I love your magazine you'll sent me on your different parts.. I cannot wait to order some of them!)

Lee

allanlane5

The amount of current a Servo takes depends a lot on the thing the Servo is connected to. If it is 'stalled', the current goes way up. All you can really use are 'typical' values, until you've built a prototype and measure it.

Having said that, you can go to Futaba's web-site, and look for the 3003 (or 148) models, and get all the facts. The most useful rating for a servo is the ounce-inches of torque it can put out, by the way, but I certainly understand your concern for current useage.