NSK MEGATORQUE M-ESB-YSB2020AB300 - Page 180

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7.1. General Operation and Function
7.1.15. Target Proximity/In target ‘(NEARA and NEARB)
à The NEARA or the NEARB signal outputs only when one of the positioning
command among AD, AR, ID or IR is executed in Programmable Indexer
positioning or the RS-232C communication command operation.
à When the Motor gets in the target area and then the output once closed, it
remains closed until an input of next positioning command.
à The NEARx output opens if the target position and stopped position of the
Motor are different because of an interruption of positioning or Servo OFF,
etc.
2
In-target mode (Data other than 0 is set to the parameter NMA or NMB)
l This is a control signal to report that the Motor is in or has passed through the specified position
zone.
l The parameter ZAS or ZBS sets the point to start outputting NEARx, while The ZAE or the ZBE
sets the point to stop outputting the signal.
l The NEARx output closes from the beginning to the end in counting up direction of the
coordinate value, while it opens in the other zone.
l The output signal may be held for a time set by the parameter NMA or NMB when the target
zone is too narrow and the velocity is too fast.
Figure 7-18: Sequential timing of NEARA and NEARB outputs
Closed
Open
Minimum output holding time
Example: NMA0.5 (50 ms)
NEARA output
In-target mode
NMA
¹
0
Motor position
50 ms 50 ms
ZAE
ZAS
+
–
ZBS
ZBE
Closed
Open
Minimum output holding time
Example: NMB1 (100 ms)
NEARB output
In-target mode
NMB
¹
0
100 msec
ZAE
ZAS
ZBS
ZBE
+–
NEARB closes.
NEARA closes.
à The NEARx output does not close if the home position has not been defined.
à If the coordinate data of ZAS and ZAE, or ZBS and ZBE are the same, the
signal outputs for only one point on the coordinate.
à If the positive and negative direction of position scale is reversed by the
parameter DI1, the CCW will be the direction in counting up.