There are several important related indicators when the watch uses the instrument to test the swing amplitude.
Swing drop:
The watch is in two states: full string and after 24 hours of actual running. Measure the swing amplitude changes of the five positions on two planes (top and bottom) and three vertical planes (bottom, left, and top). Compared with the same position, take the largest difference as the swing drop. The swing drop is also an important indicator of the isochronous performance of the watch. It can also reflect the quality of the starting bar and hairspring and their design and assembly. Usually the drop is required to be below 50 degrees.
Swing and stand difference:
When the watch is in the full-string state, the plane position of the watch face is compared with several vertical positions. Take the largest difference as the swing level difference. The swing level is also an important indicator of the position error performance of the watch. It is usually required that the adjustment difference is below 50 degrees.
The minimum swing of the facade in 24 hours:
The watch has been running for 24 hours. The minimum swing of the vertical plane (the left position is generally selected) cannot be lower than 180 degrees. The performance of the watch is better in the case of high swing than in the case of low swing. Especially for watches with calendar attachments. The minimum swing requirement of the 24-hour façade is particularly important.