Why does the electric contact pressure meter sometimes stop when the contact reaches the upper limit of the pointer?
The upper contact is not in contact with the pointer contact. Set the upper and lower electric contact pressure gauge, pressure rise, pressure gauge pointer moving upward, moving the pointer and limit contact with the pointer beyond the limit point will be disconnected, and the upper limit is reached the limit set. Because the hydraulic station valve generally has different degrees of leakage, the pressure will gradually decrease, the pointer dropped to the lower limit, it will give the letter power and then step up.
The upper contact is not in contact with the pointer contact.
You first check whether the line is normal, the method is to take the pressure gauge wiring open, directly with wire short to see if the relevant control components can normal action. If normal, then the fault should be on the electric contact of the pressure gauge.
