Figure. 5.4.4 - 172. Result of the above-mentioned example.
In the example figure above, the RTD card's Sensor 1 is used for tap position indication. With these
settings the measured resistance (0...180
Ω
) is transferred to the tap position 1...19. To use this
scaling settting, please select the option "Scaled input" for the "Tap position status" parameter.
Tap position measured from digital input voltage
If none of the above possibilities (RTD, mA, binary coding or BCD coding) are available, it is also
possible to use a digital input channel to measure the voltage over the tap changer through a resistor
and then use this to indicate the tap changer position. The setup procedure is nearly identical to the
RTD measurement option setup (as described above), except the desired digital input voltage is
selected as the tap position source.
VVolta
oltage r
ge reg
egula
ulation se
tion setttings ("A
tings ("Activ
ctive se
e setttings")
tings")
The settings presented in this subsection can be changed online by changing the setting group.
The target voltage and the control window where the voltage should be kept need to be set for the
regulator in percentage of the nominal value. When setting up the parameters for the voltage window
one should consider the regulating sensitivity and the minimizing of control operations. An
unnecessarily tight voltage window may cause excessive control operations which in turn cause the
network voltage to fluctuate. The target should be a calm network that only causes necessary control
operations. A correctly set voltage window is kind to the physical tap changer and keeps the network
voltage stable during normal network events.
There are a few basic rules that apply to the setting of the parameters for the first voltage window. First,
the window should never be set below the value of the tap step effect setting, and the window should
never exceed the allowed variation loads.
Therefore, the minimum voltage window size can be calculated as follows:
A
AQ
Q-T215
-T215
Instruction manual
Version: 2.04
270
