ABB RELION 670 Series Applications Manual page 350

Section 13
Logic
SetValue : This setting is used to set the reference value for comparison when setting RefSource is
selected as
will never pickups.
RefPrefix : This setting is used to set the unit of the reference value for comparison when setting
RefSource is selected as SetValue . It has 5 unit selections and they are Milli, Unity, Kilo, Mega and
Giga.
EqualBandHigh : This setting is used to set the equal condition high band limit in % of reference
value. This high band limit will act as reset limit for INHIGH output when INHIGH is high in last
execution.
EqualBandLow : This setting is used to set the equal condition low band limit in % of reference
value. This low band limit will act as reset limit for INLOW output when INLOW is high in last
execution.
13.13.4 Setting example
Let us consider a comparison is to be done between current magnitudes in the range of 90 to 110
with nominal rating is 100 and the order is kA.
For the above condition the comparator can be designed with settings as follows,
EnaAbs = Absolute
RefSource = SetValue
SetValue = 100
RefPrefix = Kilo
EqualBandHigh = 5.0 % of reference value
EqualBandLow = 5.0 % of reference value
Operation
The function will set the outputs for the following conditions,
INEQUAL will set when the INPUT is between the ranges of 95 to 105 kA.
INHIGH will set when the INPUT crosses above 105 kA.
INLOW will set when the INPUT crosses below 95 kA.
If the comparison should be done between two current magnitudes then those current signals
need to be connected to function inputs, INPUT and REF. Then the settings should be adjusted as
below,
EnaAbs = Absolute
RefSource = REF
EqualBandHigh = 5.0 % of reference value
EqualBandLow = 5.0 % of reference value .
344
SetValue . If this setting value is less than 0.2% of the set unit then the output INLOW
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Application manual