What to do if a geared motor is overloaded?

Solutions for Geared Motor Overload

When a geared motor is overloaded, meaning the motor can rotate but the operating current exceeds the rated value, a series of measures need to be taken to solve the problem. The following is an analysis of the causes of geared motor overload and corresponding solutions:

I. Analysis of Overload Causes

**Excessive Mechanical Load:**

Main Characteristics: The motor overheats; the overload can be detected by reading the operating current on the display screen.

Solution: Check if the transmission ratio can be appropriately increased to reduce the load on the geared motor shaft. If the transmission ratio cannot be increased, consider replacing it with a motor with a larger capacity.

**Three-Phase Voltage Imbalance:**

Characteristics: Causes excessive operating current in one phase, leading to overload tripping and uneven motor heating.

Solution: First, check if the three-phase voltage on the motor side is balanced. If unbalanced, then check if the three-phase voltage at the inverter output is balanced. If the inverter output voltage is also unbalanced, the problem lies within the inverter itself. If the inverter output voltage is balanced, the problem lies in the wiring between the inverter and the motor. Check that all terminal screws are tightened and that the contactor contacts are making good contact.

False Trip:

Cause: A fault in the inverter's internal current detection section causes an excessively high current signal, leading to tripping.

Solution: Check the inverter's internal current detection section to confirm the fault and perform necessary repairs or replacement.

II. Overload Check Method

Check Motor Heating:

If the motor temperature rise is not high, check if the inverter's electronic thermal protection function preset is reasonable. If the inverter has a margin of safety, the preset value of the electronic thermal protection function should be relaxed.

If the motor temperature rise is too high, and the overload is within the normal range, it indicates that the motor is overloaded and needs to be handled according to the solutions for mechanical overload described above.

Check three-phase voltage balance:

If the three-phase voltage on the motor side is unbalanced, handle it according to the solutions for three-phase voltage imbalance described above.

Understand the operating frequency at which the circuit breaker trips:

If the motor trips at a specific operating frequency, it may be related to the load characteristics at that frequency. Further analysis of the load characteristics is needed, and the inverter or motor parameters should be adjusted to meet the load requirements.

III. Other Precautions

When handling overload problems, ensure that the parameters of the motor and inverter are set correctly to avoid overload caused by improper parameter settings.

Regularly maintain the motor and inverter, checking the tightness of the wiring terminals and the contact condition of contactors, relays, and other electrical components to ensure good electrical connections.

If the cause of the overload cannot be determined or the problem cannot be resolved, contact professional maintenance personnel or manufacturer technical support for assistance.