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Re: [PSUBS-MAILIST] Pulse/Stepping Motors
Thanks also, Lew.
Ed
Lew Clayman wrote:
>
> --- Adam <adamnr@netrover.com> wrote:
> > > What do you know about pulse motors? Is that the same thing as a
> > > stepping motor?
> > > I bought one and don't know how to use or hook it up.
>
> I believe that a pulse-modulated system works as follows:
>
> The power is provided to the motor in pulses, at some very high frequency. What the motor "sees"
> is close enough to continuous power - because of the high frequency - that it doesn't "notice" the
> difference. The frequency never changes. Internal electronics regulates all of this.
>
> What does change is the percentage of each cycle which is positive voltage, vs zero voltage. If
> the pulse is "100% on" then the motor "sees" maximum power, power all the time. If it's 50% on,
> then the motor gets power half the time, or effectively half power, so it spins slower. All zero,
> of course, is all zero and no power. You can set the percentage "on" anywhere in between. Think
> of a rapidly blinking light, blinking so fast that you can't see the blinks, just the light, which
> looks dimmer as the blink-ons become shorter than the blink-offs.
>
> Why this is "good" is because the battery is only discharged as needed, that is to say all (pretty
> much) of the power drawn from the battery goes directly (pretty much) to the motor. The other
> approach, which is to put a variable resistor between the battery & the motor, is less efficient
> because the battery is "drained" at full blast the whole time, but some of the power is diverted
> (wasted, dissapated) by the resistor.
>
> Manually pulsing the switch on a motor set to full speed, as suggested, is less precise and more
> trouble than using a pulsed controller, but amounts to much the same thing. Maybe there's a
> little more start-stop loss, but I suspect only a little.
>
> -L
>
>
> >
> > Ed,
> >
> > Forgive me for answering a question that was not addressed to me but I feel
> > I accel in this field more than other and it's a chance for me to really
> > contribute.
> >
> > A stepper motor is used in industry for systems that require a lot of
> > control. You'll notice that out of the housing you'll have many wires,
> > unlike the conventional motor which only has two. There will usally be a
> > black wire, and a series of muti coloured wires. Usally about four or five.
> >
> > The way one hooks it up, it a little more complicated the the standard
> > motor.
> >
> > The black must be grounded. and the remaining wires must be turned on in
> > the correct sequence to make it turn.
> >
> > example: five wires, one black, one red, one blue, one green, and one
> > yellow.
> >
> > To make one revolution with this hypotheticle motor, ground the black and
> > then the system has to apply power to red, then blue, then green and then
> > yellow. Never at the same time but pulse each one.... One controls the
> > speed by cutting the delay between each pulse.
> >
> > I hope this has explained it... As far as stepper vs. pulse.. I would
> > think it's the same thing... the nomenclature comming from the "pulsing"
> > of the different leads.
> >
> > Adam
> >
>
> =====
> "Yo no soy marinero / Soy capitan"
> - Traditional Mexican Lyric (La Bamba)
> =====
>
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