- Dec 19, 2004 -
Half-door crane inverter selection
Traditional cranes have been far unable to meet the current high frequency of production needs, failure, security can not be guaranteed, maintenance delays in production, these are the users do not want to happen. Therefore, high performance, ultra-safe inverter single girder cranes slowly get the user's approval. Frequency semi goliath crane not only reduces maintenance costs, but also made a comprehensive upgrade in safety. So what should we pay more attention to for the selection of frequency converter of the semi-gantry cranes?
The inverter is divided into two types: one is a universal inverter, one is a vector inverter. General Inverter is relatively cheap, some crane manufacturers in order to save costs using universal inverter. However, general purpose inverters are not suitable for use on cranes. Universal frequency conversion is characterized by constant power, vector frequency converter is characterized by constant torque. Maybe we still do not know what is the difference between the two, the following is an example to illustrate.
Half of the main girder crane is a camber, the middle of the high, low at both ends. When using a universal frequency inverter, when the car slowly travels to the middle of the main beam, the wheel may slip and may even cause the carriage to slip down. Because the universal inverter although constant power, but not constant torque, the resistance received in a certain, will appear to drive weakness. At this time, only with a quick rush past, can not meet certain conditions, while increasing the danger.
The vector inverter torque is constant. Under all grades to ensure uniform, smooth operation. This is the typical difference between a vector frequency inverter and a general purpose frequency converter. Some users may also find that single girder cranes are also frequency-converted, but the price varies greatly. Therefore, the selection of accessories to be more understanding, more comparison.