Oldham olct 80, User Manual

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8
– Preventative Maintenance
77
Chapter 8 | Preventative Maintenance
Periodic inspections ensure that the equipment and system is functioning
properly and providing reliable detection services. The section describes the
preventative maintenance procedures required and how often they are to be
performed. Inspection and maintenance must be carried out in accordance with
the current editions of EN60079-17 and eventually with any local or national
additional requirements that may apply in the country of installation.
Maintenance frequency
Gas detectors are safety devices. Oldham recommends regular testing of fixed
gas detection installations. This type of test involves injecting a standard gas of
sufficient concentration into the detector to trigger pre-set alarms. This test does
not, in any event, replace a full calibration of the detector.
Frequency of gas testing depends on the industrial application in which the
detector is used. Inspection should occur frequently during the months following
installation start-up; later it may be spaced out if no significant problem is
observed. If a detector does not react upon contact with gas, it must be
calibrated. Calibration frequency will depend on the results of these tests
(moisture, temperature, dust, etc.); however, the device should be calibrated at
least once per year.
The site manager is responsible for implementing the safety procedures at the
site. Oldham is not responsible for implementing safety procedures.
OLCT 80
Periodic maintenance involves the following steps:
■
Remove dust from the sensor's protective housing, using a dry cloth only.
Do not use water or any type of solvent.
■
When using the equipment in dusty explosive atmospheres, the equipment
should be thoroughly cleaned on a regular basis to prevent the build-up of
dust. If a layer of dust does build up on the detector, this layer may not
exceed 5 mm.
■
Replace the screws: use high-quality screws > A4.70.
■
Perform the zero test with clean air: follow the steps described under Sensor
calibration on page 45 in the event of deviation.
■
Perform the gas sensitivity test: follow the steps described under Sensor
calibration on page 45 in the event of deviation.