ABB RER615 - Page 144

3.17.1.13 RS function block
Function block
Figure 76: Function block
Functionality
The RS flip-flop output Q can be set or reset from the S or R inputs. R input has a
higher priority over the S input. Output NOTQ is the negation of output Q.
The statuses of outputs Q and NOTQ are not retained in the nonvolatile
memory.
Table 139: Truth table for RS flip-flop
S R Q
0 0 0
1
0 1 0
1 0 1
1 1 0
Signals
Table 140: RS Input signals
Name Type Default Description
S BOOLEAN 0=False Set Q output when
set
R BOOLEAN 0=False Resets Q output
when set
Table 141: RS Output signals
Name Type Description
Q BOOLEAN Q status
NOTQ BOOLEAN NOTQ status
1
Keep state/no change
Basic functions 1MRS758755 C
144 REC615 & RER615
Technical Manual