The primary causes of high current or high temperature in the motor of a forward-curved double-inlet centrifugal fan unit are as follows.

The primary causes of high current or high temperature in the motor of a forward-curved double-inlet centrifugal fan unit are as follows.

1. During equipment startup, the damper or gate valve in the outlet duct is not locked. 2. Low motor input voltage or single-phase power supply failure. 3. The medium conveyed by the forward-curved double-inlet centrifugal fan is excessively cold (i.e., gas density is too high), causing motor overload. 4. Mismatch between system performance and fan performance. Although system resistance is low, the fan operates in a low-pressure, high-flow operating range due to significant reserve capacity.