2
UR21S-MOI-IT-W-ML-10-22-Rev0
Watts Water Technologies, Inc.
EN
General
Power supply 10 Power supply 10÷28Vdc. Sensitive elements:
•
Catalytic (S and P), Infrared (I) or Semiconductor (T) for flammable gases,
•
Electrochemical cell (S or P), Infrared (I) or Semiconductor (T) for toxic and refrigerant gases.
Up to three intervention thresholds. Automatic counting of the lifetime of the sensors.
LED on the sensor body to indicate the operating status and display option.
Use
UR21S detectors are used to detect, by diffusion, the presence of:
Methane Gas, code 0940571N; LPG, code 0940572N; Carbon Monoxide (CO), code 0940573N. Other gases are on request.
The UR21S detectors are designed for Stand-Alone operation with a 4÷20mA output and for interfacing with the CIVIC1 and
CIVIC4 Central Units.
Operation
In case of a gas leak the sensor compares the measured concentration value with the intervention thresholds set by activating the
relays or the resistive outputs (if provided) associated with them. The information of the measured concentration value is always
present on the 4 ÷ 20mA output
Technical Characteristics
Sensor type
Catalytic, Infrared, or
Semiconductor
Electrochemical Cell or
Semiconductor
Detectable Gas
Explosive Gases
(2)
Toxic Gases (e.g.: CO)
Power supply
10÷28Vdc
10÷28Vdc
Maximum Power Consumption (@ 28Vdc with
4÷20mA with s.c. output)
2,4W
(4W with UZR20.4)
1.2W
(2,8W with UZR20.4)
Measuring range
0÷100% LEL
(3)
0÷500 ppm
Precision (Catalytic, E.C., NDIR)
±5% of Full Scale. ±10% readout
Precision (Semiconductor)
±10% of Full Scale (on calibration point)
Repeatability
±5% of Full Scale. ±10% readout
Measurement Resolution (Sensivity)
1% LEL
5 ppm
Microprocessor Resolution
4096 points (12 bit A/D Converter)
Digital Filter system
Kalman Filter and zero drift compensation
Watch dog
External, acting on the whole Safety Chain
Warm-up Time
< 2 minutes after every power on
Stabilization Time
2 hours from first power on
Response Time (Max)
< 20s (T50), < 60s (T90)
Average Sensor Life (in Air)
255 weeks
255 weeks
Output 4÷20mA signal type:
Proportional Output
(default)
Step Output
(1 o 2 thresholds application)
Settable reference of 4÷20mA signal
- 4mA = 0% LEL; 0 ppm
- 20mA = 100% LEL; 500 ppm
- 0mA = no Alarm
- 10mA = 1st Threshold Alarm
- 20mA = 2nd Threshold Alarm
With jumpers (reference to negative or positive of power supply)
Load Resistance of 4…20mA output (with
generator limited to 24mA)
Minimum
0Ω @ 28Vdc
Maximum
300Ω @ 10Vdc
Operation and storage conditions:
Environment Temperature (°C)
- Operating
- Storage
-20 ÷ 50 or -40 ÷ 70 (Extended Range)
-20 ÷ 70
Relative Umidity (%UR) without condens.
- Operating
- Storage
15 ÷ 90
45 ÷ 75
Operating Pressure (KPa)
80 ÷ 120
Air Speed (m/s)
≤
6
Optical Signalling
Red LED visible on the sensor body
Dimensions and Weight
See dedicated paragraph
ATEX Marking
II 3G Ex nA nC d IIC T6(1) Gb
-20°C ≤ TA ≤ +50°C
-40°C ≤ TA ≤ +70°C (Extended Range)
Manufacturer EsiWelma
