HVAC Motors : Split Phase Motors

 Introduction to Split Phase Motor:

  • The motor is a two-pole motor with run and start windings in the stator.

  • Start winding is added out of phase to provide proper rotation direction and get the motor turning.

Operation at Startup:

  • Power is applied to both the run and start windings, initiating rotor movement.

  • Troubleshooting:

    • Measure resistance with an ohmmeter.

    • Run winding resistance (R and C terminals) should be measurable, e.g., 2 ohms.

    • Start winding resistance (S and C terminals) is typically higher, e.g., 8 ohms.

Winding Characteristics:

  • Run Winding: Located on the outer edge, connected to power.

  • Start Winding: Smaller wire, more turns, and connected in parallel to the run winding.

Circuit and Phase Shift:

  • Both windings are in the circuit at startup.

  • Centrifugal Switch:

    • Used to remove the start winding from the circuit once the motor reaches ~80% of its rated speed.

    • Not suitable for compressor motors due to potential damage from refrigerating oil.

Centrifugal Switch Operation:

  • Switch is placed in series with the start winding.

  • As the motor speeds up, centrifugal force opens the switch, de-energizing the start winding.

  • Motor continues running on the run winding alone.

Motor Type:

  • This split phase motor is referred to as a "repulsion start induction run motor."

  • Typically used for low starting torque applications.


No comments:

Post a Comment

Mechanics Introduction

  산업 역학에서 작업(work), 에너지(energy), 힘(force), 그리고 동력(power) 간의 관계를 이해하는 것은 작업의 효율성을 극대화하는 데 필수적입니다. 역학은 에너지, 힘, 그리고 동력이 함께 작용하여 작업을 수행하는 방식을 연구...