When the crane motor starts, the rotor must be connected with additional resistance to limit the average value of the starting current not more than twice the rated current of each operation, commonly used JZR and YZR series audio interface ic. Divided into two types of open and protective, installation can be stacked with each other, more than four boxes should be placed on the metal rack, the adjacent two groups of audio interface ic should be 80mm between the interval, the middle can be installed with heat insulation board, When installing the open audio interface ic, a barrier should be added to prevent the staff from accidentally touching the audio interface ic live body and grounding screw.
The selected audio interface ic should be matched with the motor model, power, power-on duration, controller model and other parameters. When wiring, the bridge should be used to detect the resistance and total resistance value of each section, and the specified numerical error range should be within ±15%. And according to the manufacturer provided audio interface ic resistance value distribution table data on the correct connection. The audio interface ic used by the two motors of the truck operating mechanism or the double trolley tower crane should be of the same manufacturer and the same model, so that the resistance values of each section are close, and the resistance difference caused by the length of the wire connected to the audio interface ic and the resistance values of the internal resistance of the motor rotor should be avoided. The mechanical characteristics of the two drive motors are identical.
Dust and metal oxides on the resistance elements should be cleaned regularly to facilitate heat dissipation. Regularly check whether the components are broken and short circuit phenomenon, whether the insulation porcelain is damaged, whether the fastening screws are loose, regularly measure the audio interface ic insulation resistance to the ground, the resistance value should be above 0.5MΩ.
When the temperature of the resistance of each section is higher than the ambient temperature of 350 ° C, the capacity of the audio interface ic should be considered to increase, and the capacity of the audio interface ic is lower than 100 ° C. Note The audio interface ic has sufficient capacity.
If the audio interface ic is broken, the resistance of the broken section can be short-circuited for emergency use. Change the job as soon as it is finished. Hard solders such as brass, silver or copper phosphorus should be used for audio interface ics that are welded and broken.
Two motors of the same type driven at the same time (such as large motor), if one of the rotor winding is re-wound, the rotor winding resistance value is reduced, a group of resistance components can be installed in a vacant position in the resistance box and connected between the audio interface ic and the motor rotor line, so that the rotor winding resistance value of the two motors is consistent.
audio interface ic https://www.unikeyic.com/products/1003001442453888/NL3S22SMUTAG.html