KMB NOVAR-1 Series, Руководство по эксплуатации

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Novar 1xxx KMB systems
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If in doubt about correctness of determining the type of connection, experimental validation is
convenient: after automatic connection configuration detection process you can usually compare the
power factor value shown by the controller with information on the billing electricity meter (ratio of
revolutions of active and reactive electricity meters). If in discrepancy, you have to set the type of
connection configuration to the other value and repeat the validation test.
4.1.11 Parameter 17 – Metering Voltage Transformer (VT) Turns Ratio
This parameter allows specifying the voltage transformer turns ratio from 10 to 5000 or it can be set as
unspecified.
Parameter is unspecified by default: “
---
“ is displayed. In this event it is assumed that the
measurement voltage is connected directly. Measurement voltage values are then displayed in volts.
If the measurement voltage is connected via a voltage transformer, its turns ratio can be specified in
this parameter (example: if a voltage transformer with conversion 35kV/100V is used, 350 is entered).
If no voltage transformer turns ratio is specified, all voltage and power measurement values as well as
U
NOM
(parameter 18), C/k
MIN
(parameter 22), and each section’s power (parameter 25) displayed as
transformed to the voltage transformer’s secondary side. If the voltage transformer turns ration is
specified correctly, the aforementioned values are displayed as values corresponding to the voltage
transformer’s primary side and voltages are shown in kilovolts.
The value specified in parameter 17 does not affect the controller’s control operation in any way; it
only affects displayed values that are voltage or power. Therefore the value may be specified later,
after the automatic section power recognition process, without having to start this process again.
4.1.12 Parameter 18 – Compensation System Nominal Voltage (U
NOM
)
Parameter U
NOM
determines the compensation system nominal voltage in volts or, if the voltage
transformer turns ration value is entered in parameter 17, in kilovolts. It is phase voltage or line
voltage, depending on the type of measurement voltage (parameter 15).
If the type of connection is specified manually (parameter 15), parameter U
NOM
is preset to its default
value – for phase voltage (
U=LN
U=LN U=LN
U=LN
) U
NOM
is preset to 230 V, for line voltage (
U=LL
U=LL U=LL
U=LL
) to 400 V. The
actual U
NOM
value is further entered by the controller within each automatic connection
configuration detection process to one of the values in Table 3.1 depending on the measurement
voltage value.
Unless the compensation system nominal voltage value is untypical, it is usually not necessary to
change the U
NOM
value recognized. If otherwise, the parameter value can be edited from 50 to 750 V
(if voltage transformer conversion is used, the value is displayed in kV after conversion).
Undervoltage and overvoltage alarm threshold values (parameter 31,32) are related to the U
NOM
value.
The U
NOM
parameter value can by at any time later edited without affecting each section’s actual
power value (parameter 25). Sections’ actual power values (for example as they were detected in the
latest automatic section power recognition process) are kept in the controller, only their displayed
nominal values, which are related to the U
NOM
value, are affected.
4.1.13 Parameter 20 – Automatic Section Power Recognition Process
The controllers are shipped with default setting of enabled automatic section recognition power
process (parameter 20 set to A,
AC=A AC=A AC=A AC=A
). With this setting, the controller carries out the automatic
section power recognition process on controller powerup (introduction of power supply voltage) if none
of the compensation sections is specified at a valid power value (see parameter 25). This condition
always takes place with the first installation or
initialization of the controller or after unsuccessful
previous automatic section power recognition process. If at least one of the compensation sections is
at valid power value, the automatic section power recognition process is not carried out.