Quick Question about a DC Motor
Archiver
Posts: 46,084
If you reverse the leads on the motor DC motors will reverse direction. This
can be done with a relay or a group of transistors.
Jim Johannsen
jim@j...
Original Message
From: MP1428@a... [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=tr4O-r91ZN7x39tdREGvDBDpgcyZfrAkRPV2QxVebrodCx4vt_6rpKnEIUtlTrj9p19GmHfJDSXT]MP1428@a...[/url
Sent: Sunday, October 19, 2003 5:18 PM
To: basicstamps@yahoogroups.com
Subject: [noparse][[/noparse]basicstamps] Quick Question about a DC Motor
I'm a beginner with motors, and I just need to produce a simple forward and
backward rotation; I don't care about accuracy. I understand that a DC motor
is
simpler to use than a Stepper Motor? And if that's true, my next question
is:
Is it possible to rotate a DC motor in the backward direction?
[noparse][[/noparse]Non-text portions of this message have been removed]
To UNSUBSCRIBE, just send mail to:
basicstamps-unsubscribe@yahoogroups.com
from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
can be done with a relay or a group of transistors.
Jim Johannsen
jim@j...
Original Message
From: MP1428@a... [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=tr4O-r91ZN7x39tdREGvDBDpgcyZfrAkRPV2QxVebrodCx4vt_6rpKnEIUtlTrj9p19GmHfJDSXT]MP1428@a...[/url
Sent: Sunday, October 19, 2003 5:18 PM
To: basicstamps@yahoogroups.com
Subject: [noparse][[/noparse]basicstamps] Quick Question about a DC Motor
I'm a beginner with motors, and I just need to produce a simple forward and
backward rotation; I don't care about accuracy. I understand that a DC motor
is
simpler to use than a Stepper Motor? And if that's true, my next question
is:
Is it possible to rotate a DC motor in the backward direction?
[noparse][[/noparse]Non-text portions of this message have been removed]
To UNSUBSCRIBE, just send mail to:
basicstamps-unsubscribe@yahoogroups.com
from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
Comments
backward rotation; I don't care about accuracy. I understand that a DC motor is
simpler to use than a Stepper Motor? And if that's true, my next question is:
Is it possible to rotate a DC motor in the backward direction?
[noparse][[/noparse]Non-text portions of this message have been removed]
direction. One of many ways to do this is with a double pole double throw relay.
If you choose this method, be sure to include a diode across the relay coil.
The diode is connected cathode (end with a line) to the positive side of the
relay coil.
Ken
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
In a message dated 10/19/2003 5:19:08 PM Pacific Daylight Time,
MP1428@a... writes:
I'm a beginner with motors, and I just need to produce a simple forward and
backward rotation; I don't care about accuracy. I understand that a DC motor
is
simpler to use than a Stepper Motor? And if that's true, my next question is:
Is it possible to rotate a DC motor in the backward direction?
[noparse][[/noparse]Non-text portions of this message have been removed]
> If you reverse the leads on the motor DC motors will reverse
direction. This
> can be done with a relay or a group of transistors.
>
> Jim Johannsen
> jim@j...
The common way is an H-Bridge. very simple, uses 4 main transistors,
2 pnp, 2 npn.
although an H-Bridge in not inherently a speed control, you can
puslse the transistors to get a sorta speed control.
Google H-bridge.
the more power you want to use, the more protection you should think
of adding.
The only problem with relays is that the relays are mechanical and
may fail. but the trade off for a little less silicon is a little
more space and money. (ie: resistors are more $$ and bigger)
Dave
>
>
Original Message
> From: MP1428@a... [noparse][[/noparse]mailto:MP1428@a...]
> Sent: Sunday, October 19, 2003 5:18 PM
> To: basicstamps@yahoogroups.com
> Subject: [noparse][[/noparse]basicstamps] Quick Question about a DC Motor
>
> I'm a beginner with motors, and I just need to produce a simple
forward and
> backward rotation; I don't care about accuracy. I understand that a
DC motor
> is
> simpler to use than a Stepper Motor? And if that's true, my next
question
> is:
> Is it possible to rotate a DC motor in the backward direction?
>
>
> [noparse][[/noparse]Non-text portions of this message have been removed]
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the
Subject and
> Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/terms/
main transistors,
2 pnp, 2 npn."
But if you are new to electronics a relay may be your best bet at this time,
and if the relay fails (which is very rare) the motor will simply turn only
one direction depending on the relay failure.
An "home brew" H bridge if not properly designed or controlled will ruin your
transistors if you get the wrong pair turned on at the same time, however,
with some logic gates to control the H bridge, this should never happen.
If you use a LMD18200 from National, you should not have any worries and is a
better solution than a relay, but a little pricey.
http://www.national.com/ds/LM/LMD18200.pdf
Also check out http://www.dprg.org/tutorials/1998-04a/
although an H-Bridge in not inherently a speed control, you can
puslse the transistors to get a sorta speed control.
Google H-bridge.
the more power you want to use, the more protection you should think
of adding.
The only problem with relays is that the relays are mechanical and
may fail. but the trade off for a little less silicon is a little
more space and money. (ie: resistors are more $$ and bigger)
Dave
[noparse][[/noparse]Non-text portions of this message have been removed]
opposite direction. For schematics to control these with a stamp check out
http://www.geocities.com/jimforkin2003/
jim
Original Message
From: MP1428@a... [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=y_SbelyS5_-dQRQA65HxZigH1PD5dOLmeYz7d0nZ5XWQhnt6PrP7HwkE0Y_kF_FRmnaJf-A0lG8]MP1428@a...[/url
Sent: Sunday, October 19, 2003 8:18 PM
To: basicstamps@yahoogroups.com
Subject: [noparse][[/noparse]basicstamps] Quick Question about a DC Motor
I'm a beginner with motors, and I just need to produce a simple forward and
backward rotation; I don't care about accuracy. I understand that a DC motor
is
simpler to use than a Stepper Motor? And if that's true, my next question
is:
Is it possible to rotate a DC motor in the backward direction?
[noparse][[/noparse]Non-text portions of this message have been removed]
To UNSUBSCRIBE, just send mail to:
basicstamps-unsubscribe@yahoogroups.com
from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
can rotate DC motor backward.
a very easy way is using a DPDT switch see the
attachment
oscar
panama city, rep. of panama
--- MP1428@a... escribi
jim http://www.geocities.com/jimforkin2003/
Original Message
From: Oscar Andrade [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=gHTLrGnCEZ_3cYBRYmFabQUuaqHz051YCNtH3sF4tzpGknffIPeigNYx2fBRPx4wn0XsvGM37HS83XHCGmw]oscar_andrade@y...[/url
Sent: Monday, October 20, 2003 9:07 PM
To: basicstamps@yahoogroups.com
Subject: Re: [noparse][[/noparse]basicstamps] Quick Question about a DC Motor
yes, DC motor are simpler then steppers and yes you
can rotate DC motor backward.
a very easy way is using a DPDT switch see the
attachment
oscar
panama city, rep. of panama
--- MP1428@a... escribi