SSX-Ⅱ型线切割机床卷丝电机,是靠两只5A的水银开关摆动一定角度交换B、C两相电源,完成正、反向转动的。其电路如图1所示。由于水银开关反向频繁,加上卷丝电机的惯性影响,虽然在卷丝电机的三相电源上加了三只15的限流电阻,水银开关所承受的换向起动电流仍然较大,因此,水银开关触头经常烧坏。如遇水银开关摆动角度 SSX-Ⅱ Wire Cutting Machine Volume wire motor, is by two 5A swing switch swing angle B, C two-phase power supply, complete positive and negative rotation. The circuit shown in Figure 1. Due to the frequent reversal of the mercury switch and the inertia of the winder motor, although three 15 current-limiting resistors are added to the three-phase power supply of the winder motor, the commutation starting current sustained by the mercury switch is still large, , Mercury switch contacts often burn out. In case of mercury switch swing angle