Society of Robots - Robot Forum

Mechanics and Construction => Mechanics and Construction => Topic started by: Carter05 on August 26, 2008, 11:21:20 AM

Title: 130c dc motor questions
Post by: Carter05 on August 26, 2008, 11:21:20 AM
I have recently picked up some 130v dc motors and was wondering what I could use to drive them. Is there something I could make myself? like a voltage multiplier of some sort? They only draw .49 amps and I don't know the stall current. Any help would be appreciated! Thanks!
Title: Re: 130c dc motor questions
Post by: ArcMan on August 26, 2008, 11:51:52 AM
What you need is a motor drive capable of driving a 130 VDC motor.  Typically, motors with higher DC voltages like this are used on industrial equipment or machine tools.  My mini-lathe at home has a 100 VDC motor.  In my personal experience, I have not seen any hobby robotics driven with that high of a voltage.  It's not very convenient because you would have to have about 11 12VDC batteries in series to get the 130VDC needed to drive that motor.  It's also quite dangerous for a hobbyist.  130 VDC can easily kill you.
Title: Re: 130c dc motor questions
Post by: pomprocker on August 26, 2008, 01:04:56 PM
i have a 130vdc motor that i control with AC using a speed controller i found on a surplus site for $30.

input is 120vac, output is a smooth 130vdc. theres even a place to hook up a pot to control the speed.
Title: Re: 130c dc motor questions
Post by: Carter05 on August 26, 2008, 01:13:04 PM
Ya I know about the AC speed controllers but I want to use it on a robot since they were free. I actually do have lots of 12v lead acids I could put together to get 132vdc and run em but it would be really heavy! If I remember right voltage multipliers work but the current capacity goes down drastically, so I would be wasting a lot of energy. Hmm....Anymore ideas?
Title: Re: 130c dc motor questions
Post by: ArcMan on August 27, 2008, 09:31:33 AM
Ya I know about the AC speed controllers but I want to use it on a robot since they were free. I actually do have lots of 12v lead acids I could put together to get 132vdc and run em but it would be really heavy! If I remember right voltage multipliers work but the current capacity goes down drastically, so I would be wasting a lot of energy. Hmm....Anymore ideas?

That is incorrect.  Wiring batteries in series adds their voltages together, but does not affect the current supplying capacity of the batteries.  The current supplying capacity of the series will be equal to the capacity of the smallest (lowest current supplying capacity) battery.
Title: Re: 130c dc motor questions
Post by: Carter05 on August 27, 2008, 09:40:47 AM
Ya I know about the AC speed controllers but I want to use it on a robot since they were free. I actually do have lots of 12v lead acids I could put together to get 132vdc and run em but it would be really heavy! If I remember right voltage multipliers work but the current capacity goes down drastically, so I would be wasting a lot of energy. Hmm....Anymore ideas?

That is incorrect.  Wiring batteries in series adds their voltages together, but does not affect the current supplying capacity of the batteries.  The current supplying capacity of the series will be equal to the capacity of the smallest (lowest current supplying capacity) battery.

Sorry I meant using a voltage multiplier circuit, not the batteries themselves, like a transformer kind of.
Title: Re: 130c dc motor questions
Post by: ArcMan on August 27, 2008, 10:38:02 AM
Oh, right.  I actually read your post wrong.   :P