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Mach Discussion => General Mach Discussion => Topic started by: jchal3 on December 13, 2009, 09:29:13 PM

Title: 3vdc outputs
Post by: jchal3 on December 13, 2009, 09:29:13 PM
This may be a dumb question, but I was having trouble getting any voltage through my parallel port, so I started reading this forum, and was able to figure that problem out.  The problem now is that my parallel port is putting out 3Vdc as opposed to the 5Vdc that is required by my drivers.  Is this going to be a problem, and if it is does anyone now how to fix it?

Thanks,
Title: Re: 3vdc outputs
Post by: RICH on December 13, 2009, 09:58:53 PM
jchal3,
Some PP cards are dual voltage ( ie; 3 or 5 volts ) and can be set with a jumper. Others are single voltage.
So if it's a tower you can buy a card with the correct voltage. The signal to your drives  ( a square wave goes from a low to a high) and your drives may not accept the lower voltage. Have you tried hooking up a drive and motor to see if it works? 
RICH
Title: Re: 3vdc outputs
Post by: Peter Homann on December 13, 2009, 10:00:02 PM
This may be a dumb question, but I was having trouble getting any voltage through my parallel port, so I started reading this forum, and was able to figure that problem out.  The problem now is that my parallel port is putting out 3Vdc as opposed to the 5Vdc that is required by my drivers.  Is this going to be a problem, and if it is does anyone now how to fix it?

Thanks,


Hi,

What you need is a way to convert the 3.3V signals to 5V. The MB-02 breakout board I make and sell can do that for you.

http://homanndesigns.com/store/index.php?main_page=product_info&products_id=59

Cheers,

Peter.
Title: Re: 3vdc outputs
Post by: jchal3 on December 13, 2009, 10:35:02 PM
Rich,

I haven't tried it yet with the drives.  So you are saying that there is a chance that there is a jumper on my pp card that will allow me to make it a 5v output?  I will check that out.  But you are also saying that there is achance that the 3v output will be enough.  Am I understanding all of that correctly?

Title: Re: 3vdc outputs
Post by: RICH on December 13, 2009, 11:57:05 PM
Yes, Look and see or get the info on it. I have a laptop that puts out 3.7 volts and works fine with my drives. The board that Peter mentioned may be an easier solution then a new PP card. Not all PP cards are equal ( some don't work, so buy localy with the understanding that if dosen't you get your money back, if not, walk away!)
RICH
Title: Re: 3vdc outputs
Post by: jchal3 on December 14, 2009, 06:35:48 AM
Rich,

Thanks for the help,

I have to get the right power supply to my driver, and then i'm going to give it a shot.

Title: Re: 3vdc outputs
Post by: Fastest1 on December 19, 2009, 11:10:58 AM
Did you ever just plug it in and try it?
Title: Re: 3vdc outputs
Post by: jchal3 on December 19, 2009, 11:47:27 AM
haven't had the chance yet.  I have to find the correct power supply for the motors first.  Looks like i'm going to have to buy a power supply.  The motors are 65vdc at 7.9amps each.  I have on other forums trying to figure out how to get to this voltage.  The consensus so far is that they are not going to need that much power, and I can get away with a 24dc with about 6 amps.  Once I get this taken care of I can give the signals a shot.
Title: Re: 3vdc outputs
Post by: Fastest1 on December 20, 2009, 11:42:37 PM
I believe the current and not the voltage that is the critical factor, maybe somebody else will chime in.
Title: Re: 3vdc outputs
Post by: jchal3 on December 21, 2009, 07:10:48 AM
fastest,

That is what I meant.  Little mistake.  I am having trouble getting 8amps per motor, but it seems like that is a max, and I could get away with less.  Some poeple are even saying that I should go less to make the motors smoother.  I'm not sure on this stuff.  Anyway I will get it worked out. 

Sorry for the confusion.
Title: Re: 3vdc outputs
Post by: Hood on December 21, 2009, 07:20:03 AM
Are these motors Servos? If so you will  need the rated  voltage if you want to get the rated  speed and same for the current, if you want the torque you will need the current.
Hood
Title: Re: 3vdc outputs
Post by: jchal3 on December 21, 2009, 09:14:35 AM
hood,

They are nema 42 steppers.
Title: Re: 3vdc outputs
Post by: M250cnc on December 21, 2009, 09:22:01 AM
fastest,

That is what I meant.  Little mistake.  I am having trouble getting 8amps per motor, but it seems like that is a max, and I could get away with less.  Some poeple are even saying that I should go less to make the motors smoother.  I'm not sure on this stuff.  Anyway I will get it worked out. 

Sorry for the confusion.

For speed think high voltage

For torque think amps

I would go for high voltage, as next you will be complaining that the machine is too slow.
Title: Re: 3vdc outputs
Post by: Hood on December 21, 2009, 09:26:21 AM
Well normally steppers have low voltage, usually about 5v. Are these old motors?
Not an expert on steppers, or anything else for that matter ;) but normally you go 5 to 20 times the voltage of the stepper with the modern type drives.
The same holds true I think in that voltage will give you speed and current torque but on steppers especially too high a current will give lots of heat.
What are the motors off? are they the sigmas off a Bridgeport? What drives are you to be using?

Hood
Title: Re: 3vdc outputs
Post by: jchal3 on December 21, 2009, 12:08:34 PM
Hood,

They are off of a piece of packaging machinery.  They are Pacific Scientific powerpac motors.  The plate says 65dc @ 7.9amps  300w.  I'm not sure if that is a max or what, but it's going to be hard to get that kind of power in a household environment.  They are Nema 42 with 2 stacks. ( i guess that's how you say it)   I have no idea what the stacks mean.
Title: Re: 3vdc outputs
Post by: jchal3 on December 21, 2009, 12:09:36 PM
Almost forgot.  They are driven with three pacific scientific 5410-010 drivers which i haven't managed to get the connection schematics for yet.
Title: Re: 3vdc outputs
Post by: Hood on December 21, 2009, 12:13:34 PM
To get the speed you will need to get the 65V , or as close as you can, I would say.

Hood