The tower crane inverter switchboard has fundamental differences with the simple contactor switchboard, which is due to the use of the inverter for more accurate and optimal control of the tower crane motors. Below I mention some important differences between these two types of panels:
1. The speed control:
• In the inverter switchboard, the inverter is used to control the speed of the motor continuously and with high precision. This makes the speed of the tower crane adjustable during loading and unloading and avoids sudden shocks. • In a simple contactor switchboard, the motor speed is controlled by turning the contactors on and off, and the motor speed is constant and does not have precise adjustment.
2. SAVE Energy Consumption:
• The inverter switchboard uses less energy due to its ability to accurately control current and voltage and reduces energy costs. • The contactor switchboard usually consumes more energy due to the lack of current control.
3. Increasing the useful life of the engine:
• By using an inverter, the motor gradually reaches the desired speed and sudden changes in voltage and current are avoided, which, as a result, increases the useful life of the motor. • In the contactor switchboard, due to the high current entering the motor suddenly, the depreciation of the motor is higher and its useful life is reduced.
4. Soft control (Soft Start/Soft Stop):
• The inverter switchboard allows soft start and stop, which is especially important for heavy cranes. This feature helps reduce mechanical shocks and increases cargo security. • In the contactor switchboard, the motor starts moving or stops suddenly with a shock, which can damage the mechanical parts.
5. More safety and precision:
• The inverter provides more safety for the operator and load due to features such as precise position control and speed limit. • In the contactor panel, due to being limited to contactors and high inaccuracy, the probability of errors and accidents is higher.