When setting up the tap changer settings, it would be ideal to have the mA difference between each
step be identical. However, this is not how it goes most of the time, and sometimes this non-linear
increase can cause the AVR function to assume that the tap position has changed two or zero steps
when in actuality the tap changer has been controlled for one step. This problem can be corrected by
using the "Scaled input" mode, and then scaling the output value of the tap position that comes from
the mA inputs at
Measurement
→
AI (mA, DI volt) scaling. Below is an example where the tap changer
has 18 positions and the mA/position curve has been corrected at two points between the minimum
and maximum positions.
Figure. 5.4.4 - 170. Example of Scaled input setting.
External mA input
There is an alternative to using an RTD & mA card: one can also use an external mA unit
(ADAM-4016) which connects to the RS-485 port.
Binary coded inputs
A
AQ
Q-T215
-T215
Instruction manual
Version: 2.04
267
