ABB RELION 620 Series Technical Manual page 317

1MRS757644 F
620 series
Technical Manual
GUID-5D79BE18-92AB-4BDC-8731-D57299D5286A V1 EN
Figure 156: Effective start value for voltage step characteristic
The voltage slope characteristic is achieved by assigning different values to Voltage
high limit and Voltage low limit. The effective start value calculation is based on the
equations.
Voltage level
U < Voltage low limit
Voltage high limit
U ≥
If Voltage low limit ≤ U < Voltage high limit,
A- I >


I > (effective)=A -
 
C - D


GUID-ABAAC011-1BC7-4606-AE60-FEC25E6CE155 V1 EN
A set Start value low
Start value
I> set
C set Voltage high limit
Voltage low limit
D set
Here U represents the measured input voltage. The voltage slope characteristic is
graphically represented.
Effective start value (I> effective)
Start value low
Start value


(C -U)
 ⋅



Section 4
Protection functions
(Equation 7)
311