Watts UR20S Series, Technical Data Sheet

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Gas detector in metal housing (Group II protection mode, category 3G, Ex nA IIC T6) with
operating status indicator light, for indicating gas alarms by means of a 4-20 mA analogue
output or a trip threshold (pre-alarm, level 1 and 2 alarm, fault) that can be freely set with DIP
switches. Power supply: 11-28 VDC. Signal output: 4-20 mA. An explosion-proof version is
available to order, marked with the ATEX hexagon symbol and designation II 2G, Ex d IIC T6.
Compliant with Directives EMC 2014/30/EU and ATEX 2014/34/EU.
II 3G, Ex nA IIC T6.
UR20S
Type Part No. DN Protection Weight (Kg)
UR20S 0940571 NATURAL GAS IP55 0.65
UR20S 0940572 LPG IP55 0.65
UR20S 0940573 CO IP55 0.65
UR20S Series gas detectors are used for detecting inflammable or toxic gases in classified areas in industrial environments
and boiler rooms. All models can be used with CIVIC1 Series control units (one sensor) and CIVIC4 Series control units (up
to 4 sensors) or with other control units set up to receive a 4-20 mA signal (generally combined fire/intrusion detection systems).
Description
Technical features Natural gas and LPG Carbon monoxide
Sensor type Standard catalytic, pellistor
or semiconductor
Electrochemical cell
or semiconductor
Power supply 11-28VDC 11-28VDC
Maximum power consumption 3.2 W 1.5 W
Measuring range 0-100% LEL 0-500 ppm
Precision (excluding semiconductor) + 5% of full scale, + 10% of reading
Precision (semiconductor) + 10% full scale (at setpoint)
Measurement resolution 1% LEL 5 ppm
Microprocessor resolution 1024 pixels (10 bit) 1024 pixels (10 bit)
Safety circuit Internal watchdog
Warm-up time < 2 mins. < 2 mins.
Stabilisation time < 2 mins. < 2 mins.
Maximum response time < 20s (T50), < 60s (T90)
Average service life of sensor in air 255 weeks 255 weeks
4 - 20 mA output signal:
Proportional output signal 4mA = 0% LEL 4mA = 0 ppm
(default) 20mA = 100% LEL 20mA = 500 ppm
Threshold-based output signal 0mA = no alarm 0mA = no alarm
(applications with 1 or 2 thresholds)
10mA = 1st threshold = 20% LEL 10mA = 1st threshold = 100 ppm
20mA = 2nd threshold = 40% LEL 20mA = 2nd threshold = 200 ppm
4-20mA output reference selection jumpers with ref. to power supply negative or positive
Fault sensor 22 mA 22 mA
4-20mA output load resistor
< 200Ω at 12VDC power supply < 200Ω at 12VDC power supply
200Ω-700Ω at 24VDC power supply 200Ω-700Ω at 24VDC power supply
Ambient temperature (°C):
Operation -20÷50°C -20÷50°C
Storage -20÷70°C -20÷70°C
Ambient relative humidity:
Operation 15%-90% non-condensing 15%-90% non-condensing
Storage 45%-75% non-condensing 45%-75% non-condensing
Operating pressure 80-110 kPa 80-110 kPa
Ambient air speed < 6 m/s < 6 m/s
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Watts Water Technologies, Inc.