SIEMENS
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Siemens IC 10 · 2017
Relays
SIRIUS 3UG45, 3UG46 Monitoring Relays for Stand-Alone Installation
Level Monitoring
Level monitoring relays
10
■
Overview
SIRIUS 3UG4501 monitoring relay
The 3UG4501 level monitoring relay is used in combination with
2 or 3-pole sensors to monitor the levels of conductive liquids.
■
Benefits
•
Can be used worldwide thanks to wide voltage range from
24 to 240 V
(absolute limit values)
•
Individually shortenable 2 and 3-pole wire electrodes for easy
mounting from above/below
•
Bow electrodes for installation from the side, for larger filling
levels and minimum space requirements
•
Can be flexibly adapted to different conductive liquids through
analog setting of the sensitivity from 2 to 200 k
•
Compensation for wave movements through tripping delay
times from 0.1 to 10 s
•
Upstream or downstream function selectable
•
All versions with removable terminals
•
All versions with screw or spring-type terminals
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Application
•
Single-point and two-point level monitoring
•
Overflow protection
•
Dry run protection
•
Leak monitoring
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Technical specifications
3UG4501 monitoring relays
The principle of operation of the 3UG4501 level monitoring relay
is based on measuring the electrical resistance of the liquid be-
tween two immersion sensors and a reference terminal. If the
measured value is lower than the sensitivity set at the front,
the output relay changes its switching state. In order to exclude
electrolytic phenomena in the liquid, the sensors are supplied
with alternating current.
Two-point control
The output relay changes its switching state as soon as the liquid
level reaches the maximum sensor, while the minimum sensor is
submerged. The relay returns to its original switching state as
soon as the minimum sensor no longer has contact with the
liquid.
OVER, two-point control
UNDER, two-point control
Note:
It is also possible to connect other resistance sensors to the Min
and Max terminals in the range 2 to 200 k
, e.g. photoresistors,
temperature sensors, encoders based on resistance, etc.
The monitoring relay can therefore also be used for other appli-
cations as well as for monitoring the levels of liquids.
11/14
A
1/A2
t
t
11/12
t
t
NSB0_01799b
Max
Min
t
= Delay 0,5 - 10 s
> 0,5 s +
t
RESET
t
t
t
t
t
= Delay 0,5 - 10 s
> 0,5 s +
t
RESET
NSB0_01800b
Max
Min
11/14
A
1/A2
11/12
© Siemens AG 2016