ABB FSO-21 - Page 371

Configuration 371
Example 1 (no encoder):
• Original SLS4 limit 100 rpm
• Original SLS4 trip limit 102 rpm
• Zero speed value 12 rpm
In this case, the difference between original SLS4 and SLS4 trip limits is smaller than
25 rpm. Trip limit is scaled to at least 2 rpm higher than the SLS4 limit. When the
scaling value is 10% or less, trip limit is determined by the zero speed value.
Example 2 (no encoder):
• Original SLS4 limit 100 rpm
• Original SLS4 trip limit 150 rpm
• Zero speed value 12 rpm
In this case, the difference between original SLS4 and SLS4 trip limits is greater than
25 rpm. SLS4 limit and trip limit are scaled down normally from 100% to 50%. When
the scaling value is 50%, the difference between the limits is 25 rpm and it stays
A Scaled SLS4 trip limit
B Scaled SLS4 limit
C Zero speed value FSOGEN.51
D The difference between scaled SLS4 limit and trip limit (2 rpm)
E Minimum value for scaled SLS4 trip limit determined by the zero speed value (12 rpm)
Speed
Scaling value (%)
100
0
50
A
B
C
D
E
10