Siemens 3UG4 User Manual page 240

3UG458. insulation monitoring relay
9.4 3UG4582/3UG4583 insulation monitoring relays
If the measured value undershoots the set threshold in the case of the 3UG4582 insulation
monitoring relays, output relay K1 drops out. If the measured value overshoots the threshold
including hysteresis, output relay K1 picks up.
The principle of operation of the 3UG4583 insulation monitoring relays can be configured via
DIP switch 4:
In the functional principle 1 x 2 changeover contacts, both output relays K1 and K2 respond
to threshold R1 (warning). The settings of threshold R2 have no influence on the principle of
operation. If the measured value undershoots the set threshold, the output relays switch to
the fault status. If the measured value overshoots the set threshold including hysteresis, the
output relays revert to the original state.
In the functional principle 2 x 1 changeover contacts, output relay K1 responds to threshold
R1 (shutdown) and output relay K2 responds to threshold R2 (warning). If the measured
value undershoots the set threshold R2 (warning), output relay K2 switches. If the measured
value undershoots the set threshold R1 (shutdown), output relay K1 switches. If the
measured value overshoots the set threshold R1 (shutdown) including hysteresis, output
relay K1 reverts to the original state. If the measured value overshoots the set threshold R2
(warning) including hysteresis, output relay K2 reverts to the original state.
All operating states of the 3UG4582/3UG4583 insulation monitoring relays are displayed via
three LEDs.
Additional monitoring functions
The 3UG4582/3UG4583 insulation monitoring relays also have two further functions.
The devices monitor the terminals
detected on one of the connected conductors, output relay K1 switches to the fault state (on
the 3UG4583, both output relays K1 and K2). The 3UG4583 also has an open-circuit
detection function that can be shut down and automatically tests the measuring signal inputs
L+ and L- at system start. This open-circuit test can be repeated at any time during operation
by activating the test function (Test/RESET button). On the 3UG4583, open-circuit detection
can be switched on (ON) and off (OFF) using DIP switch 3.
The 3UG4582/3UG4583 insulation monitoring relays monitor the ungrounded AC system,
DC system, or AC/DC system for impermissibly high system discharge capacity. If the
system discharge capacity is too high, output relay K1 switches to the fault state (on the
3UG4583, both output relays K1 and K2 switch to the fault state). If incorrect settings that
could result in a malfunction are made on the 3UG4583, the output relays switch to the fault
state. If, for example, an insulation warning value is set that is lower than the selected
shutdown threshold, this results in a parameterization error.
You will find the switching states of the output relays below in the Section "Function
diagrams (Page 243)" and in the Chapter "Diagnostics (Page 253)".
You will find the setting ranges and factory settings of the available parameters, and the
definitions of the DIP switch positions in the Chapter "Operator control (Page 249)".
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and KE cyclically for open circuit. If an open circuit is
Manual, 05/2016, NEB927043002000/RS-AC/004
3UG4 / 3RR2 monitoring relays