Chapter 4 Explanation of Functions

Note 1: Since the inverter positions the motor shaft within two turns while decelerating the motor, do not specify a high frequency as the home search speed. Otherwise, the inverter may trip during home search because of the overvoltage protection function.

Note 2: For setting the home search stop position, the periphery of the motor shaft is divided into 4,096 sections to determine points No. 0 to No. 4095, beginning at the reference point in the direction of forward rotation. (The division into 4,095 sections is irrelevant to the encoder pulse-per-revolution (PPR) setting.) The reference point is specified as the point at which the Z pulse inserted between the EZP pulse and EZN pulse signals is detected. Figure 7-2 shows the layout of the reference point and target stop positions on the periphery of the motor shaft viewed from the load side of the motor shaft (in case of positive-phase connection).

Position indicated by Z pulse

Reference point

Motor shaft viewed from the motor load side

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Hitachi SJ700-2 instruction manual 10243072 2048