Stepper motor voltage?
Hello everyone,
I'm using a stamp to drive a stepper with a SN754410NE
(L293D clone). I've got the stepping sequence and code working with a 9
volt stepper that's 37 ohms/winding. This motor has only 25 steps per
revolution. I would like to use another small stepper I have, the same NEMA
size, that has 200 steps per revolution. I do not know the operating
voltage of this motor but the resistance per winding is awfully low at 1.33
ohms. What voltage is typical for this rating? I would really like to get
this working, but suspect that it's going to draw too much current for my
driver chip. Any ideas?
Duncan
I'm using a stamp to drive a stepper with a SN754410NE
(L293D clone). I've got the stepping sequence and code working with a 9
volt stepper that's 37 ohms/winding. This motor has only 25 steps per
revolution. I would like to use another small stepper I have, the same NEMA
size, that has 200 steps per revolution. I do not know the operating
voltage of this motor but the resistance per winding is awfully low at 1.33
ohms. What voltage is typical for this rating? I would really like to get
this working, but suspect that it's going to draw too much current for my
driver chip. Any ideas?
Duncan
Comments
I have seen ads for steppers as low as 3.3 volts. As a start, I would
assume your stepper is made for 3-5 volts. At 3.3 volts, it would draw 2.3
amps; and 3.8 amps at 5 volts. The IRL530N logic-level mosfet from Digikey
is great for this. It can handle up to ~15 amps, and has on resistance of
0.11 ohms driven from a stamp. I drove a 5 volt, 1.44 amp stepper, (3.5 ohm
coils), from these devices with hardly any temp rise on the IRLs when driven
from a PIC. It is a good idea to use a series resistor between the Stamp
pin and the mosfet gate to prevent oscillations of the FET as well as giving
some protection to the Stamp. You can use 1-5 kohms. If your stepper is
bipolar you need a bootstrapped full bridge with the N-channel devices, or
use two N-channels and two P channels, (IRF9Z34 may work, but they are not
logic level devices).
Ray McArthur
Original Message
From: <orthner@s...>
To: <basicstamps@egroups.com>
Sent: Tuesday, August 15, 2000 5:11 PM
Subject: [noparse][[/noparse]basicstamps] Stepper motor voltage?
>
> Hello everyone,
> I'm using a stamp to drive a stepper with a SN754410NE
> (L293D clone). I've got the stepping sequence and code working with a 9
> volt stepper that's 37 ohms/winding. This motor has only 25 steps per
> revolution. I would like to use another small stepper I have, the same
NEMA
> size, that has 200 steps per revolution. I do not know the operating
> voltage of this motor but the resistance per winding is awfully low at
1.33
> ohms. What voltage is typical for this rating? I would really like to get
> this working, but suspect that it's going to draw too much current for my
> driver chip. Any ideas?
motor's rated voltage is to obtain the rated current. If you raise the
voltage, the current will increase. If you lower the voltage, you will also
lower the current, however youmight not have enough torque to make the motor
turn under load. You can start out at a low voltage and increase it until
the motor runs. You might have to resort to a heavier driver chip to handle
the current. I have often run 12 volt steppers at 24 and even 48 volts to
generate enough torque to make the motor move under load. This will cause
the motor to draw considerably more currnet. You might want to use a UDN2998
chip as the driver. Cost is less than $7 and manufacturer is Allegro. You
can look at the data sheet at www.allegro.com The chip is good for several
amps continuous and even more if run intermittently. You will have to change
the truth table for stepping as the chip has enable A, phase A, enable B and
phase B inputs. It will drive either unipolar (6 or 8 wires) or bipolar (4
wires) motors. I have a BS2 program that will run this chip and enable you
to talk to the controller via the serial port on your pc. I also have a
program written for the 16F84 PIC microcontroller (about $6) that works with
the Allegro chip as well. If interested, I will be glad to email you either
or both programs.
Best regards,
Gary
G. Shearer
Free Electron Laser Research Center
Vanderbilt University
Nashville, Tennessee
Original Message
From: orthner@s... <orthner@s...>
To: basicstamps@egroups.com <basicstamps@egroups.com>
Date: Tuesday, August 15, 2000 4:12 PM
Subject: [noparse][[/noparse]basicstamps] Stepper motor voltage?
>
> Hello everyone,
> I'm using a stamp to drive a stepper with a SN754410NE
>(L293D clone). I've got the stepping sequence and code working with a 9
>volt stepper that's 37 ohms/winding. This motor has only 25 steps per
>revolution. I would like to use another small stepper I have, the same NEMA
>size, that has 200 steps per revolution. I do not know the operating
>voltage of this motor but the resistance per winding is awfully low at 1.33
>ohms. What voltage is typical for this rating? I would really like to get
>this working, but suspect that it's going to draw too much current for my
>driver chip. Any ideas?
>
>Duncan
>
>
>
BS2 or another PIC. can you send me your programs and possibly some
explanations with them and schematics. Did you see my post from earlier
today with the subject of ...Speaking of stepper motors...? Thanks
-Dan
Original Message
From: "G. Shearer" <g.shearer@v...>
To: <basicstamps@egroups.com>
Sent: Tuesday, August 15, 2000 3:39 PM
Subject: Re: [noparse][[/noparse]basicstamps] Stepper motor voltage?
> I have done a lot with steppers, stamps and pics. I have found that the
> motor's rated voltage is to obtain the rated current. If you raise the
> voltage, the current will increase. If you lower the voltage, you will
also
> lower the current, however youmight not have enough torque to make the
motor
> turn under load. You can start out at a low voltage and increase it until
> the motor runs. You might have to resort to a heavier driver chip to
handle
> the current. I have often run 12 volt steppers at 24 and even 48 volts to
> generate enough torque to make the motor move under load. This will cause
> the motor to draw considerably more currnet. You might want to use a
UDN2998
> chip as the driver. Cost is less than $7 and manufacturer is Allegro. You
> can look at the data sheet at www.allegro.com The chip is good for several
> amps continuous and even more if run intermittently. You will have to
change
> the truth table for stepping as the chip has enable A, phase A, enable B
and
> phase B inputs. It will drive either unipolar (6 or 8 wires) or bipolar (4
> wires) motors. I have a BS2 program that will run this chip and enable you
> to talk to the controller via the serial port on your pc. I also have a
> program written for the 16F84 PIC microcontroller (about $6) that works
with
> the Allegro chip as well. If interested, I will be glad to email you
either
> or both programs.
>
> Best regards,
> Gary
>
> G. Shearer
> Free Electron Laser Research Center
> Vanderbilt University
> Nashville, Tennessee
to run steppers with a 16f84 and Allegro chip. I would sure like to have a
copy of your program Gary. I have a zillion hard drive motors and would
like to drive a few.
My e-mail is w5tnj@c... thanks ==MAC==
fine! (or at least until i accidentally stall the motor)
Hope this helps,
Edward Kindler
I would be glad to send along a paper I wrote using the PIC. It has diagrams
of the discussion and the final circuit. It would be very easy to modify the
circuit for a stamp. You will see. If you want the stamp program, I will
look at work for it and send it along too.
Best of luck,
Gary
Original Message
From: "Gliebe-Tronics" <gliebetronics@h...>
To: <basicstamps@egroups.com>
Sent: Tuesday, August 15, 2000 7:52 PM
Subject: Re: [noparse][[/noparse]basicstamps] Stepper motor voltage?
> Hi, I am new to the world of steppers and would like to drive them with my
> BS2 or another PIC. can you send me your programs and possibly some
> explanations with them and schematics. Did you see my post from earlier
> today with the subject of ...Speaking of stepper motors...? Thanks
>
> -Dan
>
>
>
Original Message
> From: "G. Shearer" <g.shearer@v...>
> To: <basicstamps@egroups.com>
> Sent: Tuesday, August 15, 2000 3:39 PM
> Subject: Re: [noparse][[/noparse]basicstamps] Stepper motor voltage?
>
>
> > I have done a lot with steppers, stamps and pics. I have found that the
> > motor's rated voltage is to obtain the rated current. If you raise the
> > voltage, the current will increase. If you lower the voltage, you will
> also
> > lower the current, however youmight not have enough torque to make the
> motor
> > turn under load. You can start out at a low voltage and increase it
until
> > the motor runs. You might have to resort to a heavier driver chip to
> handle
> > the current. I have often run 12 volt steppers at 24 and even 48 volts
to
> > generate enough torque to make the motor move under load. This will
cause
> > the motor to draw considerably more currnet. You might want to use a
> UDN2998
> > chip as the driver. Cost is less than $7 and manufacturer is Allegro.
You
> > can look at the data sheet at www.allegro.com The chip is good for
several
> > amps continuous and even more if run intermittently. You will have to
> change
> > the truth table for stepping as the chip has enable A, phase A, enable B
> and
> > phase B inputs. It will drive either unipolar (6 or 8 wires) or bipolar
(4
> > wires) motors. I have a BS2 program that will run this chip and enable
you
> > to talk to the controller via the serial port on your pc. I also have a
> > program written for the 16F84 PIC microcontroller (about $6) that works
> with
> > the Allegro chip as well. If interested, I will be glad to email you
> either
> > or both programs.
> >
> > Best regards,
> > Gary
> >
> > G. Shearer
> > Free Electron Laser Research Center
> > Vanderbilt University
> > Nashville, Tennessee
>
>
>
>
>