Mitsubishi FX2N-10GM, Hardware / Programming Manual

Page: 217 / 274

FX Series Positioning Controllers Operation, Maintenance and Inspection 8
8-13
Operation example 4
When the DOG switch is a long way from the reverse limit switch and the DOG search opera-
tion would take too long
• If the ZRN input is turned ON in the
MANU mode or the DRVZ instruc-
tion is executed in the AUTO mode,
a machine zero return operation will
be executed.
• The zero return speed, the zero
return direction, the deceleration
time, the creep speed, etc. are set
by parameters.
• Set the parameters so that deceler-
ation and the zero signal count are
started when the front end of the
DOG reaches the DOG switch.
• When the PG0 count value reaches
t h e s p e c i f i e d v a l u e , t r a v e l i s
stopped, the clear output (CLR) is
issued, and the zero point address
(set to PARA 16) is written to the
present value register.
DOG search function
• If the DOG is in contact with the DOG switch even after
completion of a zero return operation, the system will
automatically escape from this situation before perform-
ing the zero return operation.
• Automatic escape is also possible when the limit
switches are connected to the servo amplifier and not to
the positioning unit.
PARA 9 :
Deceleration
time
PARA 13 : Zero return speed
PARA 15 : Zero return direction
Initial
position
PARA 14 :
Creep speed
The number of zero point
signals set to PARA 17
must allow for the number
of pulses required for
deceleration distance.
PARA 16 :
Machine zero point
address
CLR :
Clear output
DOG
DOG
switch
Front
end
Count start timing
DOG input logic
PG0 : Zero point signal
PARA 17 :
Number of zero
point signals
Count is started
PARA 18 :
PARA 19 :
*
* Adjust to ensure that the DOG switch actuation point is
within the period between two consecutive PG0 pulses.
In order to make adjustment easier, the zero return
speed must be made as low as possible.
DOG switch
DOG
Zero position
Escape operation