Solar Dish w/Motor Mind B tracking
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I was here years ago with a solar dish and now have results with a
question.
The solar dish PV concentrator tracks the sun with 4 photo resistors,
2 Motor Mind B, Basic Stamp2, and two 12 VDC gear motors - about 0.3
and 1.2 amps max. The Motor Minds work very well with this tracker.
The solar dish is at http://www.harbornet.com/sunflower/pvdish.html
This is work in progress and today's task is to determine the size
and type of capacitors to put across the motor leads to reduce motor
hum and vibration during STOP commands. The motors are driven at
various speeds in both directions.
I saw one reference to 47uf in the archives, is this correct? Must it
be not polarized or can I use an electrolytic cap?
I am new to this list.
Thanks,
Doug.
question.
The solar dish PV concentrator tracks the sun with 4 photo resistors,
2 Motor Mind B, Basic Stamp2, and two 12 VDC gear motors - about 0.3
and 1.2 amps max. The Motor Minds work very well with this tracker.
The solar dish is at http://www.harbornet.com/sunflower/pvdish.html
This is work in progress and today's task is to determine the size
and type of capacitors to put across the motor leads to reduce motor
hum and vibration during STOP commands. The motors are driven at
various speeds in both directions.
I saw one reference to 47uf in the archives, is this correct? Must it
be not polarized or can I use an electrolytic cap?
I am new to this list.
Thanks,
Doug.
Comments
it must be an np type.
as to its value you will have to experement, but the higher the value the
longer the motor will run after you have removed its drive power.
Norm & Monda
Cozy MK IV #202
Ford V-6 Powered
Original Message
From: <fox@d...>
To: <basicstamps@egroups.com>
Sent: Thursday, July 06, 2000 1:05 PM
Subject: [noparse][[/noparse]basicstamps] Solar Dish w/Motor Mind B tracking
> I was here years ago with a solar dish and now have results with a
> question.
>
> The solar dish PV concentrator tracks the sun with 4 photo resistors,
> 2 Motor Mind B, Basic Stamp2, and two 12 VDC gear motors - about 0.3
> and 1.2 amps max. The Motor Minds work very well with this tracker.
> The solar dish is at http://www.harbornet.com/sunflower/pvdish.html
>
> This is work in progress and today's task is to determine the size
> and type of capacitors to put across the motor leads to reduce motor
> hum and vibration during STOP commands. The motors are driven at
> various speeds in both directions.
>
> I saw one reference to 47uf in the archives, is this correct? Must it
> be not polarized or can I use an electrolytic cap?
>
> I am new to this list.
> Thanks,
> Doug.
>
>
>
>
>
norm doty wrote:
>
> it cannot be polarized, as you reverse the voltage to drive it.
> it must be an np type.
> as to its value you will have to experement, but the higher the value the
> longer the motor will run after you have removed its drive power.
>
> Norm & Monda
> Cozy MK IV #202
> Ford V-6 Powered
>
Original Message
> From: <fox@d...>
> To: <basicstamps@egroups.com>
> Sent: Thursday, July 06, 2000 1:05 PM
> Subject: [noparse][[/noparse]basicstamps] Solar Dish w/Motor Mind B tracking
>
> > I was here years ago with a solar dish and now have results with a
> > question.
> >
> > The solar dish PV concentrator tracks the sun with 4 photo resistors,
> > 2 Motor Mind B, Basic Stamp2, and two 12 VDC gear motors - about 0.3
> > and 1.2 amps max. The Motor Minds work very well with this tracker.
> > The solar dish is at http://www.harbornet.com/sunflower/pvdish.html
> >
> > This is work in progress and today's task is to determine the size
> > and type of capacitors to put across the motor leads to reduce motor
> > hum and vibration during STOP commands. The motors are driven at
> > various speeds in both directions.
> >
> > I saw one reference to 47uf in the archives, is this correct? Must it
> > be not polarized or can I use an electrolytic cap?
> >
> > I am new to this list.
> > Thanks,
> > Doug.
> >
> >
> >
> >
> >
power to the Motor Mind with a gate. Both of these solutions require
using one more Stamp pin. (The stamp tracks the sun, watches user
inputs, watches the weather, keeps xtal time, and controls receiver
water flow so I need pins). Capacitors across motor leads seem to
smooth out motor hum but I am concerned about damaging the Motor Mind
with a too large capacitors. What happens if the Motor Mind is
momentarily short circuit?
--- In basicstamps@egroups.com, LarryGaminde <lgaminde@t...> wrote:
> Why not try to just short the motor leads together for stop
>
> norm doty wrote:
> >
> > it cannot be polarized, as you reverse the voltage to drive it.
> > it must be an np type.
> > as to its value you will have to experement, but the higher the
value the
> > longer the motor will run after you have removed its drive power.
> >
> > Norm & Monda
> > Cozy MK IV #202
> > Ford V-6 Powered
> >
Original Message
> > From: <fox@d...>
> > To: <basicstamps@egroups.com>
> > Sent: Thursday, July 06, 2000 1:05 PM
> > Subject: [noparse][[/noparse]basicstamps] Solar Dish w/Motor Mind B tracking
> >
> > > I was here years ago with a solar dish and now have results
with
a
> > > question.
> > >
> > > The solar dish PV concentrator tracks the sun with 4 photo
resistors,
> > > 2 Motor Mind B, Basic Stamp2, and two 12 VDC gear motors -
about
0.3
> > > and 1.2 amps max. The Motor Minds work very well with this
tracker.
> > > The solar dish is at
http://www.harbornet.com/sunflower/pvdish.html
> > >
> > > This is work in progress and today's task is to determine the
size
> > > and type of capacitors to put across the motor leads to reduce
motor
> > > hum and vibration during STOP commands. The motors are driven
at
> > > various speeds in both directions.
> > >
> > > I saw one reference to 47uf in the archives, is this correct?
Must it
> > > be not polarized or can I use an electrolytic cap?
> > >
> > > I am new to this list.
> > > Thanks,
> > > Doug.
> > >
> > >
> > >
> > >
> > >
>The Motor Mind B has a dynamic motor break pin, or I could cut IC
>power to the Motor Mind with a gate. Both of these solutions require
>using one more Stamp pin. (The stamp tracks the sun, watches user
>inputs, watches the weather, keeps xtal time, and controls receiver
>water flow so I need pins). Capacitors across motor leads seem to
>smooth out motor hum but I am concerned about damaging the Motor Mind
>with a too large capacitors. What happens if the Motor Mind is
>momentarily short circuit?
This is strictly from memory, but as I remember the Motor Mind B uses an
Allegro driver chip which is thermally protected. If overheating (for any
reason) should occur (short, overload, high ambient) the chip will shut
down before damage willl occur. It is generally NOT a recommended practice
to use embedded, self-protective safety measures to provide ordinary
functions which are otherwise provided. In the case of "must complete",
sometime there is no other alternative. This would seem NOT to be the
purpose here.
YMMV, of course. Please check with the guys at Solutions Cubed for further
information. They have always been very helpful whenever I have asked for
technical assistance.
Regards,
Bruce Bates
>--- In basicstamps@egroups.com, LarryGaminde <lgaminde@t...> wrote:
> > Why not try to just short the motor leads together for stop
> >
> > norm doty wrote:
> > >
> > > it cannot be polarized, as you reverse the voltage to drive it.
> > > it must be an np type.
> > > as to its value you will have to experement, but the higher the
>value the
> > > longer the motor will run after you have removed its drive power.
> > >
> > > Norm & Monda
> > > Cozy MK IV #202
> > > Ford V-6 Powered
> > >
Original Message
> > > From: <fox@d...>
> > > To: <basicstamps@egroups.com>
> > > Sent: Thursday, July 06, 2000 1:05 PM
> > > Subject: [noparse][[/noparse]basicstamps] Solar Dish w/Motor Mind B tracking
> > >
> > > > I was here years ago with a solar dish and now have results
>with
>a
> > > > question.
> > > >
> > > > The solar dish PV concentrator tracks the sun with 4 photo
>resistors,
> > > > 2 Motor Mind B, Basic Stamp2, and two 12 VDC gear motors -
>about
>0.3
> > > > and 1.2 amps max. The Motor Minds work very well with this
>tracker.
> > > > The solar dish is at
>http://www.harbornet.com/sunflower/pvdish.html
> > > >
> > > > This is work in progress and today's task is to determine the
>size
> > > > and type of capacitors to put across the motor leads to reduce
>motor
> > > > hum and vibration during STOP commands. The motors are driven
>at
> > > > various speeds in both directions.
> > > >
> > > > I saw one reference to 47uf in the archives, is this correct?
>Must it
> > > > be not polarized or can I use an electrolytic cap?
> > > >
> > > > I am new to this list.
> > > > Thanks,
> > > > Doug.
> > > >
> > > >
> > > >
> > > >
> > > >