Analysis of the reasons for the malfunction of the motor load starting and running with manual assistance
1. Single-phase motor
(1) Fault phenomenon: Use hand to assist the motor in forward rotation, and use hand to assist the motor in reverse rotation.
Reason: The motor starting capacitor was not connected.
2) Fault phenomenon: The starting capacitor has been connected, and the motor can be started with manual assistance, but cannot be started without assistance.
Reason: Due to the starting torque of the single-phase motor being lower than the rated torque, it is necessary to increase the motor power.
2. Three phase motor
(1) Fault phenomenon: Use hand to assist the motor in forward rotation, and use hand to assist the motor in reverse rotation.
Reason: One of the wires U, V, and W has a broken circuit, causing a phase loss and inability to start.