5 Operation
101 SD780 Series Servo Technical Manual
Full closed-loop mode:
Steps
Contents
Mechanical composition
1
Grating resolution of linear
encoder
0.0005mm
（
0.5µ m
）
2
Command unit
0.0005mm
（
0.5µ m
）
3
Electronic gear ratio
𝐵
𝐴
=
0.5
0.5
=
1
1
4
Parameter
Pn204=1, Pn206=1
5.8.9 Setting of alarm detection
The alarm detection settings (Pn252, Pn257) are shown below.
The setting of detection value excessive deviation between motor and load position (pn257) is the
difference between motor encoder feedback (position) and full closed-loop external encoder
feedback (load position). If the set value is exceeded, output=Er.d10 (alarm of excessive deviation
between motor and load position).
Pn257
Detection value of excessive deviation between motor and load position (Postion
mode).
Setting range
Setting unit
Default
Effective time
Variety
0
～
1073741824
1 Command
unit
1000
Immediately
Setting
(Note) when set to “0”, Er.d 10 is not output.
Setting of deviation coefficient (Pn252) between motor loads when full closed-loop rotation
1 turn.
Set the “coefficient of deviation between motor and external encoder” when the motor rotates for 1
turn. It can be used to prevent out of control caused by damage of external encoder, or to detect
“sliding” in belt mechanism.
◆
Setting Case
When the sliding rate of the belt is large or seriously twisted, please increase the value.
