There are two sources of speed commands: one is the analog voltage of the external input, and the other is an internal parameter. Delta’s AC Servo Drive ASDA Series’ registers allow users to set up 3 different types of speed commands, which are the internal parameters of P1-09, P1-10, and P1-11 (Unit: 0.1rpm). It can be switched by the signals SPD0 and SPD1 in CN1, explained in the following table: SPD0 and SPD1 status: 0 is open circuit, 1 is closed circuit When SPD0=SPD1=0, and if the mode is Sz, then the command is 0. Thus, if users do not need to use the analog voltage as speed commands, they can opt for Sz modes to avoid a zero shift caused by analog voltage. If the mode is S, then the command is REF. The analog input voltage and the voltage difference between GND has the range -10V ~ +10V. The speed of revolution corresponding to the voltage is adjustable (P1 – P40).