3UG4622-1AW30 Datasheet, PDF (80/114 Pages) List of Unclassifed Manufacturers – Monitoring and Control Devices

Monitoring Relays
3UG Monitoring Relays for Electrical and Additional Measurements
Insulation monitoring
for ungrounded DC networks
■ Overview
Relay for monitoring the insulation resistance between
ungrounded pure DC networks and a protective-ground
conductor:
• Measuring principle for differential current measurement
• Response threshold can be set continuously from
10 to 110 kW
• Selectable
- Auto reset function with hysteresis or
- Storage of the tripping operation
• Front selector switch for open-circuit and closed-circuit
principle for the output relay
• Test function with test buttons on the front for L+ and L-
and over terminal connections
• Switching output: 1 CO contact
• Insulation fault indicator for L+ and L- through two red LEDs
• Supply voltage indication with a green LED
• Electro-magnetically compatible according to EN 50081 and
EN 61000-6-2
■ Function
The monitoring relay measures the insulation voltage between
the positive and negative supply voltage in an ungrounded DC
network and a corresponding protective conductor.
The measurement is based on the DC residual current
measurement principle. The response value can be adjusted
steplessly in the range from 10 to 110 kW and thus can be
adapted to the corresponding conditions. If the insulation
resistance falls below the set response value, the output relay
triggers (depending on the setting of the open/closed-circuit
principle selector switch) and a fault LED lights up.
A ground fault is evaluated separately for L+ and L- and
indicated by means of a corresponding LED.
Note:
Due to the measurement principle, a symmetrical ground fault on
terminals L+ and L- cannot be evaluated.
Test function
A ground fault can be simulated using the Test L+ and Test L-
buttons on the front. If the test button is pressed for at least 1 s,
the status of the output relay changes and the corresponding
fault LED lights up.
An external test button can be connected to terminals Y1-Y3 for
L+ and terminals Y4-Y3 for L-. The function is triggered by
means of a NO contact.
Open/closed-circuit principle selector switch
The function principle of the output relay can be adjusted by
means of a selector switch on the front panel.
If the relay is to respond in the event of a fault (contact symbol
open), the open-circuit principle must be selected. If the relay
however is to trigger in the event of a fault (contact symbol
closed), the closed-circuit principle must be selected.
Note:
The position of the selector switch has no effect upon the fault
LEDs. The LEDs always light up if the insulation resistance on L+
or L– falls below the set value.
1 A 1 /A 2
2
3 ^{Y 3 /Y 4}
4 ^{Y 1 /Y 3}
5 ^{Y 2 /Y 3}
L + /P E ^{R R} H y s t
6
L -/P E
O pen-
R v a lu e
c ir c u it /
7
c lo s e d -
c ir c u it
p r in c ip le
8
1 1 /1 4
1 1 /1 2
T est = a p p ro x . 1 s
R _{H y s t} = ty p ic a lly 2 x R _x
N S B 0_01395
T e st^{> s}
1 = S u p p ly v o lta g e
2 = B u tto n o n fro n t -
R esetL+ and L- /
T estL+
3 = B u tto n o n fro n t - T e s t L -
T e s t r e m o te c o n n e c tio n -
T estL-
4 = T e s t r e m o te c o n n e c tio n -
T estL+
5 = T e s t r e m o te c o n n e c tio n -
S to re , re s e t
6 = In s u la tio n r e s is ta n c e R
o f s u p p ly
s e t r e s p o n s e v a lu e R
7 = S w itc h o n fr o n t
O p e n - c ir c u it /
c lo s e d - c ir c u it p r in c ip le
8 = N O c o n ta c t
Fault storage and RESET
If terminals Y2 and Y3 are linked, the monitoring relay is set to
fault storage mode.
If the insulation resistance falls below the set value, the output
relay triggers (depending on the setting of the open/closed
circuit selector switch), and stays in this state even if the
insulation resistance rises again above the hysteresis value
(typical: 2 times the set value). This fault storage can be deleted
by pressing and releasing the L+ RESET button, opening the
Y2-Y3 connection or by switching off the supply voltage.
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Siemens LV 1 T · 2006