MSA 47K Series, Руководство по эксплуатации

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GB
MSA SAFETY REGULATIONS
Series 47K Gas Detector [SIL 2]
7
1.3. Application, Advice and Restrictions
This Manual should be carefully read by those responsible for use and
maintenance of the gas detection and monitoring system.

The series 47K catalytic sensor is suitable for the detection of gases or
vapours in air with a concentration below the Lower Explosive Limit [LEL].

The series 47K catalytic sensor cannot measure concentrations of gases or
vapours in inert atmospheres or oxygen deficient atmospheres. The European
standard EN 60079-29-2 indicates an Oxygen concentration higher than
10 vol% is necessary for correct operation of catalytic sensors.
Attention
The certification does not permit use of the series 47K sensor in
oxygen enriched atmospheres.

The series 47K catalytic sensors can be poisoned by high levels or long
exposure to certain substances present in the atmosphere being monitored.
When a catalytic sensor is installed in a place where those substances may
be present, to ensure the correct operation and measurement accuracy the
sensor should be calibrated more frequently.

The sensitivity of the series 47K catalytic sensors is reduced by the presence
of silanes, silicates, silicones, tetraethyl lead, halogen compounds, sulphurous
compounds, organic-phosphorous compounds and compounds containing:
fluorine, chlorine, iodine or bromine, therefore the sensors must be
recalibrated after exposure to these substances.

The series 47K sensor opening [sintered disc] must be protected against
water, dust and mechanical damage. During painting operations in the area
where the sensor is installed, avoid traces of paint on the sensor opening. The
paint must not interfere with the diffusion process.

Note that the sensor opening [sintered disc] must always face downwards.

After having exceeded the full scale value an increased display of measured
values can appear temporarily. During this period no calibration must be
performed.
The only method of verifying the correct operation of the sensor is to carry out a
span check using a known concentration of calibration gas in air.
For response curves contact your national MSA office.