KMB NOVAR 2600, Operating Manual

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NOVAR 2600 Operating Manual
necessary parameters in the group edited you can escape from the parameter group. Only now the
change confirmation message “
Save changes ? ” appears and only when confirmed with the

button
all of the parameter changes in the group come in effect at once. Otherwise, the changes are thrown
and the parameters stay unchanged.
4.3.1 PFC Control Setup
4.3.1.1 Target Power Factor for Tariff 1/2
The value of target power factor for tariff 1 and tariff 2 can be specified in one of three formats :
• cos φ ...cosinus of the voltage and current phasors angle; range -0,80 ÷ 0.80
• tan φ ...tangens of the voltage and current phasors angle; range -0,75 ÷ 0.75
•
φ
...voltage and current phasors angle in degrees; range -35° ÷ +35°
Negative value means lagging power factor, the positive one leading power factor.
4.3.1.2 Control Bandwidth on High Loads for Tariff 1/2
Using this parameter you can specify the control bandwidth on high loads (see Figure 4.5). The value
entered specifies the range of reactive power in the C zone which constitutes condition considered as
compensated, making the controller stop control interventions.
On low loads (zone A) and on medium loads (zone B), the control bandwidth is constant and
corresponds to the
O
MIN
value ( reactive power of the minimum output ) – the band follows the power
factor slope specified at width ±( O
MIN
)/2. On high loads (zone C) the bandwidth increases so its limits
correspond to adjustable deviation from the target power factor. For the cosinus target power factor
format , the standard bandwidth value in this zone is 0.010 or ± 0.005 – this condition is shown in the
figure. If thus, for example, the target power factor is specified as 0.98, reactive power corresponding
to power factor from 0.975 to 0.985 will be considered compensated condition in zone C.
Fig. 4.5 : Standard Control Bandwidth
The control bandwidth format is the same as the target power factor. It can be set in range
0.000÷0.040 if the target power factor format is
cosinus
; if the format is
tangens
or
angle
, the control
bandwidth range is 0.000÷0.030 or 0÷15°, respectively.
Control bandwidth increase may especially be useful in systems with large control range – avoiding
uselessly precise control on high loads reduces the number of control interventions which results in
longer contactor service life. If the parameter values is decreased to 0, the control bandwidth
corresponds to value
O
MIN
(constant, not widening).
Note: On low loads, the control bandwidth is “bent” (zone A) to prevent undesired overcompensation
(the illustration is a simplification).
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