7 Before Starting Positioning Operation
107
FX3U-20SSC-H Positioning Block User's Manual 
1
Introduction
2
System 
configuration
3
Example 
Connection
4
Installation
5
Wiring
6
Memory 
configuration 
and data 
7
Before starting 
positioning 
control 
8
Manual control
9
Positioning 
Control
10
Table Operation
7.8 Ring counter setting (Ver.1.10 or later)
Target address setting range and rotation direction
Set the target address and rotation direction as follows.
• When specifying the address with an absolute value
In interrupt 1-speed constant quantity feed (except the constant position stop mode) and interrupt 2-speed 
constant quantity feed, even if the target address and rotation direction are specified in absolute values, 
the system operates as if they are specified in relative values.
- Target address:  Set a proper address suitable for positioning operation.
The setting range is from 0 to the ring counter upper limit value in the current 
address.
- Rotation direction: Set the ring operation rotation direction for the absolute address.
In interrupt 1-speed constant quantity feed operation (constant position stop 
mode)
Specify the rotation direction using the sign of the target address 1.
+: The system will operate in the direction in which the current value will increase.
- : The system will operate in the direction in which the current value will decrease.
Reciprocal movement instruction
Set the ring operation rotation direction for the absolute address to "0: Direction for 
shorter rotation".
• When specifying the address with a relative value
In interrupt 1-speed constant quantity feed, even if the target address and rotation direction are specified in 
absolute values, the system operates as if they are specified in relative values.
- Target address: Set a proper address suitable for each positioning operation.
- Rotation direction: Set a proper direction suitable for each positioning operation.
Mechanical zero-point address setting
For enabling ring operation in the current address, set the mechanical zero-point address within the following 
range.
Setting a value outside the setting range will cause an error.
Setting range: 0 to the ring value
Unlimited length feed in ring operation (Ver. 1.30 or later)
The 20SSC-H Ver. 1.30 or later supports unlimited length feed in ring operation when the absolute position 
detection system is used.
No setting is necessary for unlimited length feed.
However, the reciprocal movement instruction does not support unlimited length feed in ring operation when 
the absolute position detection system is used.
2. Applicable positioning operations
• Operations allowing the ring operation • Operations not allowing the ring operation
- Mechanical zero return
- JOG operation
- 1-speed positioning operation
- Interrupt 1-speed constant quantity feed
- 2-speed positioning operation
- Interrupt 2-speed constant quantity feed
- Interrupt stop
- Variable speed operation
- Multi-speed operation
- Manual pulse generator operation
- Reciprocal movement instruction
 (Ver.1.10 or later)
- Linear interpolation
- Linear interpolation (interrupt stop)
- Circular interpolation