Some tap changers might work “inversely” meaning maximum mA measurement means the tap
changer is in the lowest position. If this is the case this can be switched with “Tap position indication”
parameter.
Figure. 5.5.1. - 104. Tap position indication can be switched.
Correcting non-linear mA tap position indication with current scaling
When setting up the tap changer settings it is ideal that the mA difference between each step would be
identical. Most of the time this is not the case and in some cases this non-linear ramp-up can cause
the voltage regulator function to assume the tap position has changed two steps or zero steps when
the tap changer has actually been controlled for one step. This can be corrected by scaling the tap
position output value gotten from mA inputs. Below is an example where tap changer has 18 positions
and the mA/position curve has been corrected at two points between the min and max positions.
AQ-T257
Instruction manual
Version: 2.00
© Arcteq Relays Ltd
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