janitza UMG 512-Pro, User Manual And Technical Data

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UMG 512-PRO
12.5.1 Phasor diagram examples
Here are two examples showing a visualization
of measured current and measured voltage in the
phasor diagram:
Example 1
Primarily ohmic load.
Voltage and current have
only a small deviation
in the phase position.
·The current measurement input is assigned to
the correct voltage measurement input
Example 2
Primarily ohmic load.
Voltage and current have
a deviation of about 180°
in the phase position.
·The measured current input is assigned to the
correct voltage measurement input.
·In the current measurement under consideration,
the connections k and I are reversed or there is a
feedback into the supply network.
12.6 Residual current
Only connect residual current transformers with a
nominal current of 30 mA to inputs I5 and I6!
Both residual current inputs can measure AC
currents and pulsating DC currents.
The residual current displayed by the device must
match the input current, taking into account the
current transformer ratio.
The current transformer ratio is set to 127/1 A at
the factory and may need to be adapted to the
residual current transformers that are used.
INFORMATION
·No connection diagram needs to be configured
for measurement inputs I5 and I6!
INFORMATION
The device requires the mains frequency to
be able to measure residual currents. For this
purpose, apply the measured voltage or set a
fixed frequency.