Re: [CAD_CAM_EDM_DRO] Re: LARGE DC MOTOR speed control question

In a message dated 7/15/00 12:30:48 PM Mountain Daylight Time,
hightechsystems@... writes:

<< Your voltage on 120 will be closer to 110 maybe. The
meter does not usually read the peak of the sine wave. >>
The standard meter reads RMS, this is the equivalent heating power as an
equal DC voltage, however the capacitors of a rectified power supply will see
the peak voltage, and will read 1.4 times the RMS input voltage, under no
load conditions. As soon as you load the power supply the voltage will droop
badly, how much will depend on half, or full wave rectifiers, size of
capacitor, and load applied, really more important to a technician or an
engineer than us. Use 120 volt AC input for 90 volt motors, and 220 volt AC
input for 180 volt motors, close enough for the girls we dance with.
You can also get into controllers, and there are adjustments that will help
smooth things out, also better and two types of speed regulation, armature
and field control.
You could write a book on DC motor control.
bill