ABB RELION Series Technical Manual page 754

Section 11
General function block features
748
k A
⋅
t s
 
=
   
U U
− >

B C
× −

U
>

GUID-6E9DC0FE-7457-4317-9480-8CCC6D63AB35 V2 EN
t [s] operate time in seconds
U measured voltage
U> the set value of Start value
Time multiplier
k the set value of
Table 710: Curve coefficients for the standard overvoltage IDMT curves
Curve name A
(17) Inverse Curve A 1
(18) Inverse Curve B 480
(19) Inverse Curve C 480
D
+
E



B C
1 0
32 0.5
32 0.5
1MRS758755 A
(Equation 83)
D E
0 1
0.035 2
0.035 3
REC615 and RER615
Technical Manual