janitza UMG 509, Operation Manual And Technical Data

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UMG 509
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Earthing of current transformers!
If a connection is provided for the earthing
of secondary windings, then it must
be connected to the earth.
Current direction
The current direction can be individually corrected via
the existing serial interfaces or on the device for each
phase.
If incorrectly connected, a subsequent re-connection
of the current transformer is not required.
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Open-circuit current transformers!
High voltage spikes that are dangerous
to touch can occur on current transformers
that are driven with open-circuit secondary
windings!
W i t h " s a f e o p e n - c i r c u i t c u r r e n t
transformers" the winding insulation
is rated such that the current transformer
can be driven open. However, even these
current transformers are dangerous
to touch when they are driven open-circuit.
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Current transformer connections!
The secondary connection of the current
transformer must be short circuited on this
before the current feed to the UMG 509
is disconnected!
If a test switch, which automatically short-
circuits the secondary wires of the current
transformer, is available then it is sufficient
to set this to the "Test" position insofar
as the short-circuiting device has been
checked beforehand.
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Please note!
Residual current monitoring is performed
using the terminals I5 and I6. There is no
directional sensitivity of the residual
currents of the network or load sides (not
directionally sensitive).