EW0826A4_en - rev. A
Oxygen detectors
–
URS20SS
05/10/2020
Gas detection systems for industrial environments
7/8
Checklist after
mechanical and
electrical installation
(continued)
Since the sensor scale is between 0…...30% O
2
, in air (20.9% O
2
) the 4…...20mA
output must be set between 14 and 16mA (theoretic value 15.1mA).
Use the calibration kit to apply the gas mixture at 4% of CO
2
, making sure the
4...20mA output is between 5 and 7mA (theoretic value 6.1mA); the status LED and
the pre-alarm, 1
st
and 2
nd
alarm threshold relays on the optional relay card switch on
according to the thresholds and the alarm mode settings.
Maintenance
Routine
Corrective
Decommissioning
A sensor functional test should be carried out every three-six months.
Routine maintenance involves repeating the same tests as set forth in “checklist after
mechanical and electrical
installation”.
If any abnormalities are found during routine sensor maintenance, return the sensor
concerned to the supplier / installer, who in turn will send it back to the manufacturer.
Sensors may need to be re-calibrated, using the
TUL40..
calibration kit and the
TUS40-20
handheld terminal, which must be connected to the sensor via the
communication interface integrated in the cable (on the connector
CN4
).
For the re-calibration procedure, see the instructions supplied with the handheld
terminal.
Remove power from the detector, disconnect all wiring and conduits and dismount
the housing from all the blocking systems.
Warranty
Warranty on EsiWelma products is valid for 12 months from installation date and no
longer than 24 months from manufacturing date on the product. Installation data,
stamp and signature on the data sheet filled in by the installer will be considered
proof for warranty.
A copy of the warranty data sheet must be sent when returning the product under
warranty.
Accessories
UZR20.4
Four-relay card
TUL40..
Gas calibration Kit
TUS40
Handheld terminal
CRG40
Gas collecting cone
PAP40
Powerful jets protection
Dimensions and weight
Dimensions (HxWxD): 155x100x60mm. Weight: 0.65Kg
