According to the national standard 7588, the balance coefficient should be 0.5, not less than 0.4; For some special elevators (such as perennial heavy-duty freight elevators), the balance coefficient can be appropriately increased to about 0.55;
In this way, the elevator traction machine only needs to pull 50% of the rated load regardless of whether the car is empty or full. For example, for an elevator with rated load of 1000kg, the counterweight needs a counterweight block of 500kg (ideally, not counting the weight of the car and counterweight frame and the weight of the long-floor steel wire rope).