Yaskawa MP2000 Series: Built-in SVB or SVB-01 Motion Module - Manual (Page 152)

5.1 Example Setting of Motion Parameters for the Machine
5.1.4 Position Reference
5-5
Motion Parameter Setting Examples
5.1.4 Position Reference
The target position value for position control is set for the Position Reference Setting (motion setting parameter
OL
1C). There are two methods that can be set for using the Position Reference Setting: Directly setting the coordi-
nate of the target position value as an absolute value or adding the moving amount from the previous command posi-
tion as a incremental value.
The following table lists the parameter details relating to position references.
The following table compares the advantage and disadvantage of incremental addition mode and absolute mode.
Parameter Type
Parameter No.
(Register No.)
Name Description
Default
Value
Motion Setting
Parameters
OW 09, bit
5
Position Refer-
ence Type
Specify the type of position data.
0: Incremental Addition Mode
Adds the present moving amount value to the previ-
ous value of OL
1C and sets the result in
OL 1C.
1: Absolute Mode
Sets the coordinate of the target position in
OL
1C.
Always set to 0 when using a motion program.
0
OL 1C
Position Refer-
ence Setting
Set the position data.
• Incremental Addition Mode (OW 09, bit 5 =
0)
The moving amount (incremental distance) specified
this time will be added to the previous value of
OL
1C.
OL 1C ← Previous OL 1C + Incremental dis-
tance
Example:
If a travel distance of 500 is specified and the previ-
ous value of OL
1C is 1000, the following will
occur:
OL
1C ← 1000 + 500 = 1500
• Absolute Mode (OW 09, bit 5 = 1)
The coordinate value of the target position is set.
Example:
Set 10000 to move to a coordinate value of 10000.
OL
1C ← 10000
0
Position Reference
Type
Advantage Disadvantage
Incremental
Addition Mode
It is not necessary to consider the relationship
between OL
1C and the current position when
canceling a move.
Incremental addition mode can be used for finite or
infinite length axis type.
OL 1C does not necessarily equal the coordinate
value of the target position, so the position reference
can be difficult to understand intuitively.
Absolute Mode
The coordinate of the target position is specified
directly, making it easy to understand intuitively.
The current position must be set in OL 1C when-
ever the power supply is turned ON or a move is can-
celed. If this is not done, the axis may move suddenly
when a move command is started.
R
R