janitza UMG 512-Pro, User Manual And Technical Data

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UMG 512-PRO www.janitza.com
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7.8 Residual current measurement
The device:
·Is suitable for use as a residual current monitor
(RCM) for monitoring AC currents and pulsating
DC currents.
·Can measure residual currents according to IEC/
TR 60755 (2008-01) of type A.
·Does not measure using direction selectivity.
This means there is no direction-dependent
differentiation of the residual currents of the grid
and load side.
Connection of suitable external residual current
transformers with a nominal current of 30 mA can
be made on residual current transformer inputs I5
(terminals 4/5) and I6 (terminals 6/7).
7.8.1 Failure monitoring
The device monitors the ohmic resistance at the
residual current measurement inputs.
If this is greater than 300 ohms, there is a failure of
the residual current measurement. This can occur,
for example, due to a cable break.
For more information on failure monitoring, see
the section „12.7 Failure monitoring (RCM)“ on
page 76.
CAUTION
Risk of injury or damage to the meter/your
system due to short circuit!
Inadequate insulation of the operating equipment
at the residual current measurement input with
respect to the supply circuits can cause voltag-
es at the measurement input which represent a
hazard when touched or damage to your device
or system.
· Ensure reinforced or double insulation with
respect to the supply circuits.
· Isolate residual current measurement inputs
galvanically from each other and galvanical-
ly from the supply voltage!
L2 L3 N L1
Load
PE
Fig. Connection variant, "Residual current measurement via
current transformer"
INFORMATION
·Ratios for the residual current transformer in-
puts can be configured via the GridVis
®
power
grid monitoring software.
·No connection diagram needs to be configured
for measurement inputs I5 and I6!