在正反转和行程控制电路中,各个接触器的常闭触点互相串联在对方接触器线圈电路中,其目的是为了 ( ) 。 In a positive-negitive rotating circuit the normally closed contacts of each contactor are connected in series with each other in the coil circuit of the opposite contactor in order that ( )
A.
保证两个接触器不能同时动作 (two contactors for positive rotating and negitive rotating will not run at the same time)
B.
能灵活控制电机正反转运行 (the shift between positive rotating and negitive rotating can be realized )
C.
保证两个接触器可靠工作 (to rnsure the function of two contactors for positive rotating and negitive rotating of motors )