EsiWelma Srl
URS20SE - EW0826A1_en.docx
Oxygen detectors – URS20SE
16/06/2017
Gas detection systems for industrial environments
2/8
Technical
characteristics
Type of sensor
Electrochemical cell
Detectable Gas
O
2
excess
O
2
deficiency
Power supply
11÷28Vdc
Max power consumption
2.5W
Measuring range
0…30% O
2
Precision
2,5% of full scale range (in air)
Repeatability
2,5% of full scale range
Measurement resolution
0.1% O
2
Microprocessor resolution
1024 points (10 bit)
Digital filter system
Kalman Filter
Watchdog
Internal
Warm-up time
< 2m
Stabilization time
< 2m
Response time
< 10s (T20), < 45s (T90)
Average Sensor life (in air)
120 weeks
Sensor type settings
(O
2
excess or deficiency)
S1.7 DIP switch
OFF (O
2
excess)
S1.7 DIP switch
ON (O
2
deficiency)
Threshold limit settings
(S1.8 = OFF, default):
Pre-alarm
1
st
threshold alarm
2
nd
threshold alarm
23% O
2
25% O
2
27% O
2
19% O
2
17% O
2
15% O
2
Threshold limit settings
(S1.8 = ON):
Pre-alarm
1
st
threshold alarm
2
nd
threshold alarm
22% O
2
23% O
2
24% O
2
20% O
2
19% O
2
18% O
2
4..20mA Output
Proportional mode
(default)
Consumption mode
(applications at 1 or 2
thresholds)
4…20mA Output reference
selection:
- 4mA = 0% O
2
- 20mA = 30% O
2
- 0mA = no alarm
- 10mA = 1
st
threshold alarm
- 20mA = 2
nd
threshold alarm
by jumper selectable polarity
4…20mA output load resistor
- up to 200
at 12Vdc power supply
- 200
700
at 24Vdc power supply
Operating Temperature
Storage Temperature
-20
50 °C
-20
70 °C
Relative Humidity
(without condensing)
-
Operation
-
Storage
15
90 %RH
45
75 %RH
Operating pressure (KPa)
80
110
Air speed (m/s)
6
Visual warnings
Red LED visible with detector energized
Dimensions and weight
See dedicated section
Options & Accessories
Card with 4 SPDT relays
UZR20.4
NO or NC contacts available, jumper
selectable
See threshold limit settings
Maximum relay capacity:
50mA at 24Vac/dc, 100mA at 12Vac/dc
Relay operating mode:
-
direct: relay ON when an event is
detected
-
reverse: relay ON when no event is
detected
TUL40..
Gas calibration kit
See installation and commissioning chapter
TUS40
Handheld terminal
for service and maintenance
See installation and commissioning chapter
CRG40
Gas collecting cone
See dedicated data sheet
PAP40
Powerful jets protection
See dedicated data sheet
ATEX markings
1370
II 2G Ex d IIC T6
BVI 07 ATEX 0032
-20°C
T
A
+50°C
