81 
5.4.1.2 Zero clamp (/ZCLAMP) 
1. Overview 
This  function  is  used  when  host  controller  uses  speed  command  input  and  the  servo  system  isn’t 
configured the position loop. In other words, the function will be used when the motor must stop and 
enter lock state even the V-REF input voltage is not zero.   
When set ON the zero clamp function, it will configure the position loop inside the servo, the motor 
will do zero clamp within ±1 pulse at this position. The motor will return to zero clamp position even it 
is run by external force. 
The present speed must be smaller than zero clamp speed when using zero clamp function, it can clamp 
the motor shaft from moving. The motor will switch from speed mode to position mode when starting 
the zero clamp function. At this time, rotate the motor shaft, it will return to the original position. It will 
not return to original position in speed mode, because it has no position feedback.   
 
2. Input signal setting 
Defaulted is not distribute to input 
terminal   
/Z-CLAMP  signal  is 
distributed  to  input 
terminal  by  parameter 
P5-31,  Range: 
0000-001A. 
Input signal from SI2 terminal 
 
3. Parameter setting 
 
ZCLAMP input signal is ON, forced speed command is 0, when the speed below 
P3-13, switch to position mode and the servo lock in this position.   
ZCLAMP input signal is ON, forced set the speed command to 0. 
ZCLAMP input signal is ON, the speed below P3-13, switch to position mode and 
the servo lock in the position.   
Note: after entering zero clamp mode, present setting speed is higher than P3-13, 
motor doesn’t run, the ZCLAMP signal must be OFF, then motor will run again. 
ZCLAMP  signal  is  ON,  the  setting  speed  is  less  than  P3-13,  switch  to  position 
control mode, and servo is locked at this position. At this time, if setting speed is 
over P3-13, the motor will run again. 
 
5.4.1.3 Speed reach signal (/V-RDY) 
  Related parameter 
 
 
 
Speed arrival signal output condition 
When the actual motor speed is greater than P5-05, output speed reach signal (/V-RDY).