ABB REC670 Applications Manual page 391

1MRK 511 401-UEN A
Bay control REC670 2.2 IEC
Application manual
DA
=
D
D
U
EQUATION1986 V1 EN-US
=
t
tMin
1
D
EQUATION1848 V2 EN-US
Where:
DA absolute voltage deviation from the set point
D relative voltage deviation in respect to set deadband value
For the last equation, the condition t1 > tMin shall also be fulfilled. This practically
means that tMin will be equal to the set t1 value when absolute voltage deviation
DA is equal to ΔU ( relative voltage deviation D is equal to 1). For other values see
figure 171. It should be noted that operating times, shown in the figure
30, 60, 90, 120, 150 & 180 seconds settings for t1 and 10 seconds for tMin.
IEC06000488 V2 EN-US
Figure 171: Inverse time characteristic for TR1ATCC and TR8ATCC
The second time delay, t2, will be used for consecutive commands (commands in
the same direction as the first command). It can have a definite or inverse time
characteristic according to the setting t2Use (Constant/Inverse). Inverse time
characteristic for the second time delay follows the similar formulas as for the first
time delay, but the t2 setting is used instead of t1.
t1=180
t1=150
t1=120
t1=90
t1=60
t1=30
Section 14
Control
(Equation 116)
(Equation 117)
171 are for
IEC06000488_2_en.vsd
385