Slow movement of the large and small arms caused by malfunction of the high-voltage sensor

A certain customer has oneKobelco SK200-8The excavator starts working from 5am every day, takes a 1-hour break at 12pm, and works until 8pm. During this period, there will be 2 to 3 instances of slow movement of the large and small arms around 9am to 10am, 3pm to 4pm, and 5pm. After each malfunction, simply release the operating handle for about 1 minute and the machine can resume normal operation

Cause analysis:

1. Observe that when the car has no action at high throttle, C-1 is 0.1, C-2 is 0.9M, E-1 and E-2 are both 417MA, and other data is normal
2. After a malfunction occurs, when the boom rises and overflows, C-1 is 14M, C-2 is 2M, E-1 is 630MA (normal), E-2 is 350MA (abnormal), D-1 is normal, D-2 is 750MA (abnormal, causing the working oil to flow back from the P2 unloading valve to the tank and causing slow boom movement), the horsepower is reduced to 0MA (normal), the engine speed is around 2130, and there is no stalling phenomenon. The low-pressure sensor B-1 is 3M (normal)
3. After the malfunction, the forearm recovery and outward overflow C-1 is 17M C-2 is 2M E-1 is 630MA (normal) E-2 is 350MA (abnormal) D-1 is normal D-2 is 750MA (abnormal) D-6 is 750MA (normal is 200MA)

Handling method:

1. From the service diagnosis, it can be seen that the reason for the slow movement of the large and small arms is obviously caused by the action of the P2 unloading valve. However, the reason why the P2 unloading valve will move when the large and small arms overflow is still unclear. Due to the fact that two Type 8 cars had exchanged CPUs on site, the fault still existed after the low-pressure sensor was replaced. Finally, after replacing the high-pressure sensor, a robot operator who had never operated the car before was working. According to him, there were still two brief instances of slow movement after the replacement, but I did not observe it. The second time, the robot operator who originally operated the car continued to work and has been working until now. He said that there has been no further fault phenomenon