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#148648 - 09/22/01 12:08 AM 1 Phase Motor Drawings #1
Scott35 Offline

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Registered: 10/19/00
Posts: 2707
Loc: Anaheim, CA. USA

Single Phase Split-Phase Induction Motors [Squirrel Cage Rotor]. Basic drawings and rotation reversal methods.
Note: These reversal arrangements can be applied to all motors listed in this message [1pm01 thru 1pm06].
The "Odd Ball" schematic is an alternative way to lay out the windings on a schematic. This one is the commonly used schematic symbol used in HVAC circuit schematics. Also seen a few appliance schematics [dishwashers, washing machines, refrigerators, etc.] using this type of schematic symbol.

Basic drawings of Split Phase Resistance Start and Split Phase Capacitor Start induction motors [1 phase squirrel cage rotor].

This is a Capacitor Statr / Run type motor setup. When the motor reaches near full operating speed [apx. 80% of rated speed], the centrifugal switch opens the circuit between the Auxillary [start] winding, the start capacitor, and the AC input [turns off the start circuit], then places a capacitor of much lower value into the circuit during normal operation. This is done via the SPDT start switch.
Having the Run Capacitor connecting the auxillary winding during normal operation, makes the motor more efficient and may correct the Power Factor. It does not add any Torque or Horsepower to the motor.

Dual voltage, Capacitor start motors

Dual speed, pole-changing motor with manual speed control switch

Permanent Split Capacitor motor. This is used on many ceiling fans and oscillating fans.
The speed control is done via an intregally wound Autotransformer [wound with the stator], but can be done externally with an Autotransformer [like a Variac, or simple tapped Autotransformer and physical switches] if the motor is set on the "High Speed" setting.
Capacitor and Aux. winding remain connected at all times.
The value of the capacitor is low, as compared to a starting capacitor [4 - 7 MFD as compared to 300 - 800 MFD].

Next set of 1 phase drawings will contain Repulsion motors, Shaded Pole induction, synchronous and brush type motors - including DC motors. I need to get access to some reliable information on Brushless DC motors [commonly found in your PC's power supply], so I can draw these schematics and post. Anyone with links + other info please let me know.

Discussion thread coming soon, or feel free to create one!!!

Scott SET posted 09/22/2001 @ 00:07:00
Scott " 35 " Thompson
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