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5.2.3 Location Requirements
When selecting a mounting location for the sensor the following should be taken into consideration for optimum
performance:
In the longest, straightest, unrestricted section of ductwork available.
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In metallic ductwork (for non-metallic ductwork contact Goyen | Mecair).
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Away from ambient or radiated temperatures greater than +50°C (120°F).
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Where possible, the equipment should be mounted out of direct sunlight, precipitation, and away from running
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water.
Hazardous Zones: refer to the Sensor Safety Description on page 4 for details of ATEX-related special conditions
•
and requirements.
5.2.4 Cabling Guidelines
Cables should be fixed such that they are free from excessive vibration and not under strain. Cables should
be secured in accordance with good engineering practice (e.g. using cable trays where possible) and careful
consideration should be given to the positioning of cables so that they are not damaged easily. Cables should
be routed to avoid sources of large electromagnetic fields, such as heavy switching gear. Care taken during the
installation of the cables ensures a long, maintenance-free life and avoids possible damage to the control unit
and sensor.
In summary, the cabling should be installed such that:
Heavy vibration is minimized to prevent fatigue and failure.
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It is not vulnerable to accidental damage.
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It is away from sources of large electromagnetic fields (if possible).
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5.2.5 Grounding the Sensor
For PEM sensors it is essential that the sensor body is grounded to the stack wall. This is necessary for Ex safety.
In addition, poorly grounded sensors may pick up external noise producing false high readings.
Ensure the installation complies with the following:
The sensor may only be fitted to a metal duct or stack, if the stack is not metallic or you are concerned that the
•
stack may not provide a suitably earthed shield for the sensor, please contact Goyen | Mecair.
The grounding strap (or earth wire) provided may be connected to ensure the sensor body is securely grounded
•
to the metallic stack wall. The sensor is electrically grounded to the ductwork by the mechanical connection made
between the sensor and the socket, and by the external grounding strap.
NOTE: The grounding strap must be connected between sensor enclosure and stack wall. Relying on the stack
connection only is not acceptable in hazardous areas!
When connecting the grounding strap between sensor enclosure and stack wall leave sufficient length so that the
•
sensor can be removed and placed on the ground or platform for maintenance without disconnecting.
For threaded connections: Do NOT put PTFE tape around the thread (as this can compromise the sensor grounding
•
connection)!
If necessary, remove excessive rust from the thread and socket and apply a copper-loaded grease.
•
5.2.6 Running Cables between Sensor and Power Supply
CAUTION!
Do NOT route cables where they may be at risk from lightning damage (e.g. over exposed roofs).
To prevent water from entering the instrument, mount all instruments and accessories with the cable entry
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glands facing downward.
After inserting and connecting a cable, fasten the cable glands tightly onto the cable to form a seal. Leave a little
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slack in the cores.
Cable sheathing must always penetrate the cable entry gland fully, and the gland must be fastened tightly to it.
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Where a cable run approaches the instrument from above, it must be run underneath the instrument and then
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curved up to the cable gland.
Leave sufficient slack in the cable to allow the sensor unit to be removed and placed on the ground/platform
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for servicing.
10
INSTALLATION AND OPERATION MANUAL – OWNER'S RECORD PEM MANUAL – PARTICULATE EMISSION MONITOR
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