The gear reducer can rotate, but the operating current exceeds the rated value, which is called overload.
The basic reflection of the overload of the reducer is: although the current exceeds the rated value, the extent of the excess is not large, and usually does not generate a large inrush current.If the gear reducer is overloaded, we need to find out the cause of its overload, and then use the correct method to solve the overload problem of the gear reducer.
Analysis of the specific reasons for the overload of the gear reducer:
1. The mechanical load is heavy, and the specific characteristic of the heavy load is that the machine generates heat, which can be found by reading the operating current from the display.
2. The three-phase voltage is unbalanced, causing the operating current of a certain phase to be too large, resulting in an overload trip. The characteristic is that the gear reducer generates heat unbalanced. phase current).
3. Misoperation, the current detection part inside the inverter fails, and the detected current signal is too large, causing tripping.
Checking method for gear reducer overload:
1. Check whether the gear reducer is hot. If the temperature rise of the gear reducer is not high, first check whether the electronic thermal protection function of the frequency converter is preset properly. If the frequency converter still has a margin, the electronic thermal protection should be relaxed. The default value of the function.
If the temperature rise of the machine is too high, and the overload occurs is a normal overload, it means that the load of the machine is heavy.At this time, first of all, it should be possible to increase the transmission ratio appropriately to reduce the load on the gear reducer shaft.If it can be increased, increase the transmission ratio.If the transmission ratio cannot be increased, the capacity of the engine should be increased.
2. Check whether the three-phase voltage on the machine side is balanced. If the three-phase voltage on the gear reducer side is unbalanced, then check whether the three-phase voltage at the output end of the inverter is balanced. If it is not balanced, the problem is inside the inverter. .
If the voltage at the output terminal of the inverter is balanced, the problem is on the line from the inverter to the machine. Check whether the screws at all terminals have been tightened. If there is a contactor or other electrical appliances between the inverter and the machine, check the It should be checked whether the terminals of the relevant electrical appliances have been tightened, and whether the contact conditions of the contacts are in good condition.
3. If the three-phase voltage on the machine side is balanced, you should know the operating frequency when tripping
If the working frequency of the gear reducer is low, and the vector control (or no vector control) is not used, first reduce the U/f ratio. If the load can still be driven after the reduction, it indicates that the original preset U/f ratio is too high. The peak value of the excitation current is too large, and the current can be reduced by reducing the U/f ratio; if the load cannot be carried after the reduction, the capacity of the inverter should be considered to be increased; if the inverter has vector control function, the vector control should be used method.
