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6. Operation
6.1 Modes of Display
The power factor display is independent of
the control relay operation and can be
reprogrammed at any time. To the right of
the four and a half character digital display
there are three LEDs indicating which
display mode is active, either "cos phi",
"Ampere", or "Harmonic".
Five modes of display can be selected by
pressing the appropriate button:
6.1.1 Power Factor
The "Power Factor" display mode is the
standard display and can be activated
from another mode of display by pressing
the buttons "IQ", "IP", or "Harm".
The symbols "+" for ind. and "-" for cap.
show whether the power factor is inductive
or capacitive.
The LED "Regen" indicates that generative
active power is fed back into the mains.
Active and reactive currents are measured
seprarately. The power factor (cos phi)
display value is the result of a mathemati-
cal calculation, which ensures accuracy
over the entire range down to values close
to 0. The minimum apparent current for a
correct power factor (cos phi) display is
approx. 0.02 A. When the apparent cur-
rent falls below 0.02 A for three consecu-
tive measurements one capacitor stage is
switched off and if there is no change in
the measured current, all remaining
stages are switched off and "I=0" appears
on the display.
6.1.2 Reactive Current
IQ
The display indicates the reactive current
portion in the current transformer circuit.
The "+" for ind. or "-" for cap. indicate
whether the reactive current is inductive or
capacitive . The LED "Ampere" lights up.
From this mode of display the compensa-
tion effect of the capacitor stages e.g. by
adding or removing capacitor stages
manually, can be monitored. If the current
transformer ratio (CT) is programmed via
the set mode, the actual reactive current
on the primary side of the CT is displayed.
Otherwise the current portion is displayed
and has to be multiplied by the CT ratio to
obtain the actual value.
Pres "IQ", "IP", or "Harm" buttons to exit
this mode of display.
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