Mitsubishi Electronics Q172HCPU, Q173HCPU POINT, 6 POSITIONING CONTROL, (1)Travel value after proximity dog ON

6 POSITIONING CONTROL

(1)Travel value after proximity dog ON

(a)The travel value after proximity dog ON is set to execute the count type home position return.

(b)After the proximity dog ON, the home position is the first zero-point after travel by the setting travel value.

(c)Set the travel value after proximity dog ON more than the deceleration distance from the home position return speed.

Example The deceleration distance is calculated from the speed limit value, home position return speed, creep speed and deceleration time as shown below.

[Home position return operation] Speed limit value : VP=200kpps

Home position return speed : VZ=10kpps

							Creep speed : VC=1kpps
Real deceleration time : t=TB					VZ		t
					VP
						TB		Deceleration time : TB=300ms
[Deceleration distance (shaded area under graph)]
=	1	VZ	t
	2	1000
	VZ	TB	VZ	Converts in speed per millisecond
=
	2000		VP

=10103 30010103

2000 200103

=75 . . . . . . Set 75 or more

POINT

A home position return must be made after the servomotor has been rotated more than one revolution to pass the axis through the Z-phase (motor reference position signal).

For a proximity dog type or count type home position return, the distance between the point where the home position return program is started and the deceleration stop point before re-travel must be such that the servomotor is rotated more than one revolution to pass the axis through the Z-phase.

When a data set type home position return is made in an ABS (absolute position) system, the servomotor must also have been rotated more than one revolution by JOG operation or the like to pass the axis through the Z-phase.

(Note) : When "1 : No servomotor Z-phase pass after power ON" is selected in the "function selection C-4" of servo parameter (expansion setting parameter), even if it does not pass zero point, the home position return can be executed and restrictions are lost.

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