ABB UNITROL 1020 - Page 56

Chapter 3 - Device Overview 
48 3BHS335648 E82 UNITROL 1020 User Manual
Description of parameters:
Min Slip [Hz] :
Max Slip [Hz] :
Max DeltaU[%] :
Max Delta Angle
[deg]
Minimum Slip
Maximum Slip
Max. voltage difference
Note: f
M
> f
NET
Slip always negative
Max Delta Angle [deg]
Slip
[Hz]
MinimumMaximum
-1.00 -0.40
5.0
-5.0
10.0
-10.0
[%]
0
-20
-20
-40
-60
-8080
60
40
20
0
Angle =
-10
10
UNET - UM(Delta U)
Tot CB CloseTime
[ms]
Time between closing command and closed breaker (see data
sheet of the breaker).
Voltage Offset [%]
Voltage correction factor between U
M
and U
NET
.
U
NET USED
= U
MEASURED FROM NET
+ Voltage Offset
Voltage Offset is provided in the current software release for
backwards compatibility with earlier versions.
Note 1: Voltage correction can be achieved by modifying the
Network PT parameters.
Note 2: Because Voltage Offset functions independently of other
functions, it’s recommended to leave Voltage Offset = 0 when
correcting voltage using the Network PT settings.
Angle Offset [deg]
Phase correction factor between U
M
and U
NET
. Delta angle is
calculated as follows:
Delta Angle = Phase
NET
– Phase
M
+ Angle Offset
Example
Situation: Due to a step-up transformer between machine and
grid, U
NET
is delayed 30º with respect to U
M
.
Correction needed: Angle Offset = + 30º (positive).