3UG4622-1AW30 Datasheet, PDF (78/114 Pages) List of Unclassifed Manufacturers – Monitoring and Control Devices

Monitoring Relays
3UG Monitoring Relays for Electrical and Additional Measurements
Insulation monitoring
for ungrounded AC networks
■ Overview
Relay for monitoring the insulation resistance between the
ungrounded single or three-phase AC supply and a protective
ground conductor:
• Measuring principle with superimposed DC voltage
• Two selectable measuring ranges of 1 ... 110 kW
• Stepless setting within the measuring range
• Selectable:
- Auto reset function with fixed hysteresis or
- Storage of the tripping operation
• Test function with test button and terminal connections on the
front
• Switching output: 1 CO contact
• Insulation fault indication with a red LED
• 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 resistance
between the ungrounded AC supply and an associated
protective ground conductor.
A superposed DC measuring voltage is used to perform the
measurement.
The monitoring relay is divided into two ranges for an insulation
resistance range from 1 to 100 kW. A range switch on the front
can be used to switch over between a 1 to 11 kW range and a
10 to 110 kW range. Within the selected range, the monitoring
relay can be steplessly adapted to the respective insulation
conditions.
If the insulation resistance undershoots the set threshold, the
output relay is excited and the red LED (fault display) is lit.
If the insulation resistance exceeds 1.6 times (corresponding to
60 % hysteresis) the set threshold, the output relay will return to
the rest position.
Note:
The monitoring relay is designed for AC supply systems.
Series-connected rectifiers must be galvanically isolated from
the measuring relay that is to be monitored.
1
A1/A2
A1/B2
2 Y1/Y2
3 Y1/PE
1.6 x R value
4R
R value
5
11/14
11/12
NSB0_01393 _{1 = Supply voltage}
A1-B2/A1-A2 for
115 V/230 V AC
A1-A2 for 24 ... 240 V AC/DC
2 = Remote connection-
save-reset
3 _{= Key on the front -}
test/reset
4 = Insulation resistance R
of network
Set operating value R
Test
5 = NO contact
Test = > approx. 300 ms
Test functions
The "Test" button on the front can be used to simulate a ground
fault. If the "Test" button is pressed for at least 300 ms, the output
relay is energized and the fault LED lights up. An external test
button can be connected to terminal Y1. The function is
activated by closing (> 300 ms).
Fault storage and RESET
If terminals Y1 and Y2 are jumpered, the monitoring relay is set
to fault storage mode. If the set insulation resistance is under-
shot, the output relay is excited and remains tripped even after
the insulation resistance rises above 1.6 times the set value
again. Fault storage can be reset by briefly pressing the RESET
button, briefly jumpering (< 300 ms) the Y1 and PE/ground
terminals or by switching off and on the supply voltage.
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Siemens LV 1 T · 2006