GESTRA URS 2 User manual

1
URS 2
Installation Instructions 818869-01
Limit Switch URS 2
GESTRA Steam Systems
EN
English

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Contents
Usage for the intended purpose ..............................................................................................................4
Safety note .............................................................................................................................................4
Danger ...................................................................................................................................................4
Attention.................................................................................................................................................4
ATEX (Atmosphère Explosible).................................................................................................................4
Note on the Declaration of Conformity / Declaration by the Manufacturer .........................................4
Important Notes
Page
Explanatory Notes
Scope of supply ......................................................................................................................................5
Description .............................................................................................................................................5
Function .................................................................................................................................................5
System components ...............................................................................................................................5
Design....................................................................................................................................................5
URS 2 ...................................................................................................................................................12
Attention...............................................................................................................................................12
Tools.....................................................................................................................................................12
Key.......................................................................................................................................................12
Examples of Installation ........................................................................................................................13
Installation
Electrical Connection
URS 2 ...................................................................................................................................................14
Note .....................................................................................................................................................14
Tools.....................................................................................................................................................14
Wiring diagram ..................................................................................................................................... 15
URS 2 .....................................................................................................................................................6
Corrosion resistance ...............................................................................................................................7
Name plate / marking .............................................................................................................................7
Dimensions.............................................................................................................................................8
Technical Data
URS 2 .....................................................................................................................................................9
Key.......................................................................................................................................................11
Design
URS 2 ...................................................................................................................................................10
Key.......................................................................................................................................................11
Functional Elements

3
Checking electrical connection .............................................................................................................16
Applying mains voltage.........................................................................................................................16
Contents - continued -
Commissioning
Page
Limit switch..........................................................................................................................................16
Note .....................................................................................................................................................16
Operation
Faultfinding list for troubleshooting......................................................................................................17
Operation Malfunctions
Danger .................................................................................................................................................18
Disposal................................................................................................................................................18
Decommissioning
Limit switch..........................................................................................................................................16
Performance test

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Important Notes
Danger
The terminal strips of the URS 2 are live during operation.
This presents the risk of severe cases of electric shock!
Cut off power supply before mounting or removing the terminal strips and the
housing cover.
Usage for the intended purpose
Use limit switch URS 2 only for signalling limits based on the 0/20 mA input.
Safety note
The equipment must only be installed and commissioned by qualified and competent staff.
Retrofitting and maintenance work must only be performed by qualified staff who – through adequate
training – have achieved a recognised level of competence.
Explanatory Notes
Scope of supply
URS 2
1 Limit switch URS 2
1 Installation manual
ATEX (Atmosphère Explosible)
According the the European Directive 94/9/EC the equipment must not be used in potentially explosive
areas.
Attention
The name plate specifies the technical features of the equipment. Note that any piece of
equipment without its specific name plate must neither be commissioned nor operated.
Note on the Declaration of Conformity / Declaration by the Manufacturer
For details on the conformity of our equipment according to the European Directives see our
Declaration of Conformity or our Declaration of Manufacturer.
The current Declaration of Conformity / Declaration of Manufacturer are available in the Internet under
www.gestra.en
/ documents or can be requested from us.

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Description
Universal signalling of two limits for MIN/MAX alarm based on 0/20 mA input. The equipment is con
nected to a measuring sensor with current output 0  20 mA or 4  20 mA.
Application for instance in combination with GESTRA level transmitter NRT 21b, continuous blowdown
controller LRR 15b und conductivity transmitter LRT 15b, LRT 16b or level monitoring system
NRGT 261 and conductivity monitoring system LRGT 161, LRGT 162.
Explanatory Notes - continued -
Function
In the URS 2 a MIN switchpoint and a MAX switchpoint are assigned by means of a rotary potentio
meter to the 0/20 mA output signal coming from an external measuring sensor. Once the current
output signal of the external device reaches the MIN/MAX switchpoint adjusted in the URS 2, the red
LED signals ALARM and the MAX or MIN relay contact in the URS 2 is energized.
nMIN alarm (according to the selected 0/20 mA signal)
nNormal operation
nMAX alarm (according to the selected 0/20 mA signal)
Two adjustment knobs for setting the MIN and MAX switchpoints.
Two red LEDs signal MIN and MAX alarm.
System components
NRT 2-1
Level transmitter NRT 2-1
LRR 1-5
Continuous blowdown controller LRR 1-5
LRR 1-6
Continuous blowdown controller LRR 1-6
LRT 1-5
Conductivity transmitter LRT 1-5
LRT 1-6
Conductivity transmitter LRT 1-6
NRGT 26-1
Level monitoring system NRGT 26-1
LRGT 16-1
Conductivity monitoring system LRGT 16-1
LRGT 16-2
Conductivity monitoring system LRGT 16-2
Design
URS 2
Plugin unit in plastic case for installation in contol cabinets The terminals are accessible after
removing the cover from its base. Thanks to the code plug the equipment cannot be connected
inadvertently to wrong GESTRA equipment. The equipment may be clipped onto a 35 mm supporting
rail or screwed into position on a mounting panel.

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URS 2
Technical Data
Input
For measuring sensor with current output 0 to 20 mA (with external wire link for 4 to 20 mA),
input resistance 100 Ω.
Output
2 voltfree relay contacts,
contact rating 250 V, 500 W, 3 A resistive with a life of 4 x 105switching cycles or
0.35 A inductive at 2 x 106switching cycles,
contact material: silver, hard gold plated.
Switching hysteresis
1 %
Adjustment knob
Two knobs with scales 0  100 % for MAX and MIN alarm, continuously adjustable.
Indicators
One LED for MAX alarm and one LED for MIN alarm.
Mains voltage
24 V, 110 V, 120 V, 220 V, 240 V, 50 to 100 Hz, 3.5 VA (please state voltage when ordering),
ancillary unit URN1 can also be fed with 24 V DC.
Protection
IP 40
Admissible ambient temperature
0 °C bis 55 °C
Housing material
Base: Noryl SE 1GFN 2 UL 94 VO
Weight
Approx. 0.5 kg

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URS-2 b 056733
230 V ~ 50/60 Hz 3,5 VA
PA-VI 830.27
IP 40
GESTRA AG BREMEN
TÜV.
Corrosion resistance
If the equipment is used for the intended purpose, its safety is not impaired by corrosion.
Technical Data - continued -
Name plate / marking
Equipment designation
Fig. 1
Mains supply

8
Technical Data - continued -
Dimensions
Fig. 2
106 7
32
51
Fig. 3
112
85

9
Design
Fig. 6
72 3
6
5
4
Fig. 4 Fig. 5
1
1
URS 2

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Functional Elements
URS 2
Fig. 7
a
8
9
0
MAX 55°C
MAX 95%
%
IP 20

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1 Cover screws
2Base
3Upper part of the housing
4Mounting clip
5Cable entry (flexible)
6Cable entry (housing)
7Fixing holes d = 4.3 mm
8LED MAX Alarm
9Adjustment knob for setting the MAX switchpoint
0LED MIN alarm
aAdjustment knob for setting the MIN switchpoint
Design / Functional Elements
Key

12
Tools
nScrewdriver (5.5/100)
Attention
nTo provide sufficient ventilation, ensure a minimum spacing of 20 mm between
adjacent units.
Installation
URS 2
On supporting rail
1. Clip temperature switch onto supporting rail.
2. Loosen cover screws 1 and detach cover 3 from its base 2.
3. Select cable entry 5 and remove corresponding seal.
On mounting panel
1. Loosen cover screws 1 and detach cover 3 from its base 2.
2. Unscrew mounting clip 4.
3. Drill hole 7 marked in the base to ∅ 4.3 mm.
4. Select cable entry 5 / 6 and remove corresponding seal.
5. Fix base with two M4 screws onto mounting panel.
1 Cover screws
2Base
3Upper part of the housing
4Mounting clip
5Cable entry (flexible)
6Cable entry (housing)
7Fixing holes d = 4.3 mm
8Supporting rail TS 35 x 15 DIN EN 50022
Key

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Installation - continued -
Examples of Installation
42
5
8
6
6
3
1
MAX 55°C
MAX 95%
%
IP 20
Fig. 9
Fig. 8
7
7

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Electrical Connection
URS 2
Flexible multicore control cable can be used for wiring, min. conductor size 1.5 mm2.
Tools
nScrewdriver for slotted screws, size 2.5 completely insulated according to DIN VDE 06801
Note
nThe rated voltage is indicated on the name plate.
n When switching off inductive loads, voltage spikes are produced that may impair
the operation of control and measuring systems. We recommand to provide these
consumers with commercial arc suppressor RC combinations e.g. 0.1 µF/100 Ω.

15
Electrical Connection - continued -
Wiring diagram
Fig. 10
URS 2b
123 4 56 10 11 127 8
MIN alarm MAX alarm
– +
0/4 – 20 mA
RE= 100 Ω
with wire
link
4 – 20 mA
L N
Mains

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Apply mains voltage to the limit switch URS 2.
Commissioning
Make sure that the URS 2 is wired according to the wiring diagram. Fig. 10
Checking electrical connection
Applying mains voltage
Performance test
1. Increase the 0/20 mA signal of the external measuring sensor until it exceeds the MAX
switchpoint adjusted in the URS 2. The LED 8 must light up and the MAX relay must be energized.
2. Decrease the 0/20 mA signal of the external measuring sensor until it falls below the MIN
switchpoint adjusted in the URS 2. The LED 0 must light up and the MIN relay must be energized.
Limit switch
Operation
Operation in combination with external measuring sensors, e. g. GESTRA level transmitter NRT 21b,
continuous blowdown controller LRR 15b und conductivity transmitter LRT 15b, LRT 16b or level
monitoring system NRGT 261 and conductivity monitoring system LRGT 161, LRGT 162.
Limit switch
Note
nTo analyse and eliminate malfunctions refer to section “Fault finding list for trouble
shooting” on page 17.

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Operation Malfunctions
Fault-finding list for troubleshooting
An alarm is triggered although the measured values do not pass outside the adjusted limits.
Fault: Incorrect selection of input 0 mA or 4 mA.
Remedy: Check the output signal of the sensor and adapt the input of the URS 2 accordingly.
If faults occur that are not listed above or cannot be corrected, please contact our service centre or
authorized agency in your country.

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Disposal
Decommissioning
For the disposal of the equipment observe the pertinent legal regulations concerning waste disposal.
Danger
The terminal strips are live during operation.
This presents the risk of severe cases of electric shock!
Cut off power supply before mounting or removing the terminal strips and the housing
cover.

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For your notes

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81886901/052012cm (80823402) · GESTRA AG · Bremen · Printed in Germany
Agencies all over the world:
www.gestra.de