Re: [CAD_CAM_EDM_DRO] SERVO ratings, ( was e: Xylotex / RapidSyn/ Power Supply help?

turbulatordude wrote:

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>I have to deferr to the pro's who have experiance with servos.
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>>[What about servos? The servo motors I've been looking at list
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>voltages
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>>which range between 12 and 60 VDC. (See
>>http://www.polysci.com/Documents/moc23series.PDF ) I'd been
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>assuming that
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>>this referred to the running voltage range, the motors going faster
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>as the
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>>voltage increased. Is it really a nominal voltage, as with
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>steppers, or was
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>>I correct? Will these motors run fine on the lower end of the range
>>(assuming I'm driving them with Gecko 320s), or will they
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Servo motors will have limited speed with a lower voltage supply to the
servo amp.
Some servo motors are designed for very high speed, and so you won't
lose anything
with a lower voltage. For instance, if some 48 V motor was rated at
6000 RPM at 48 V,
you would be able to get close to 3000 RPM at 24 V (neglecting loss in
the servo amp
and resistance in the motor).

>>
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>lack "pep"? There
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>>seems to be a tradeoff between volts and amps- there are motors
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>calling for
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>>fewer volts, but they want more amps. The ones running on higher
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>voltage
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>>seem to draw fewer amps.
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Power is V * A, so if you drop one, you need more of the other to
deliver the same power.
Horsepower is one unit of measuring power, Watts is another unit. 745.7
W = 1 HP.

>> Do the former go slower but with more
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>torque, while
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>>the latter go faster with less? Is there a simple way to swap amps
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>for volts
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>>in a power supply, so one has control over this?
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No. The motor's windings are configured for some specific volts/RPM
figure, called the
Kv of the motor (standard unit is V/1000 RPM).

>> For instance, if I
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>have a
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>>12v 10 amp (120 watt) supply, can I put some kind of a voltage
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>booster into
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>>the circuit and get 24v at 5 amps? I'm pretty sure this works in
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>reverse- a
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>>voltage regulator can limit the voltage, but is there a way to jack
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>it up?]
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Yes, there is. it is called a boost regulator. While linear OR
switching regulators can reduce
voltage, only a switching regulator can increase voltage. But, I don't
think this is very practical
for this purpose. In some cases, however, you can change the way the
transformer is hooked
up to get more voltage at lower current. For instance, where a
center-tapped transformer
is used with 2 rectifier diodes, you can use a 4-diode bridge rectifier
to double the output
voltage. You have to check the capacitor's voltage rating, though, to
be sure it is safe at
the new voltage.

Jon