Ampcontrol Pty Ltd
– ABN 28 000 915 542
GASGUARD CH4 GAS SENSOR USER MANUAL
GSB076 Version 6
– March/2019
Uncontrolled Copy - Refer to Ampcontrol Website for Latest Version
Page 12 of 25
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4.3 Recommendations
Select a suitable central location for mounting with good access. The location should be as clean
and dry as practicable and at a temperature as close to 20
C as practicable.
Mount the sensor unit in a position that minimises the risk of mechanical damage.
Mounting should be to a vertical surface, allowing for easy wiring access and subsequent
servicing. It is essential that the sensor be positioned to take into account the expected flow of
the gas to be measured (see Section 4.4 Sensor Location).
The sensor should not be mounted with the gas detection port pointing upwards. Positioning the
sensor in this manner could result in the gas entry holes and filter membranes becoming blocked
by water or debris. If this occurs, the sensor will likely suffer reduced sensitivity and/or extended
response times.
It is recommended that the sensor is not mounted next to electrical cables or equipment that is
likely to produce large amounts of electrical or magnetic switching noise.
4.4 Sensor Location
The relative density or buoyancy of the gas or vapour with respect to air is a very important
consideration. This determines its propensity to rise or fall when released into the atmosphere.
Gases or vapours with buoyancy less than air will tend to rise from the source of release. Conversely,
gases or vapours heavier than air will tend to fall from the source of release.
Over time, all gases will disperse and become mixed into the general surrounding atmosphere. Methane
is lighter than air and can therefore become trapped in elevated areas where low air currents prevent
mixing. Places such as corners, roof or cable spaces are examples.
For monitoring in areas where there are no air currents, mount the sensor as high as possible. For areas
that are ventilated and have good airflow, positioning is not as critical since general mixing will occur.
For these areas it is recommended to locate the sensor around, or just above head height. For
applications requiring specific detection characteristics such as at the point of potential release, proper
analysis of the site should be undertaken to determine the optimum sensor location.
4.5 Mandatory Installation Practices
The following information must be adhered to when installing the Gasguard CH4 Sensor. Failure to
adhere to this information may give rise to unsafe operation.
Using the Gasguard CH4 Sensor in a manner that exceeds its electrical, functional or physical
specifications, or in a way that is contrary to its operating restrictions, may create risks to personnel
and/or equipment resulting in injury or death.
The sensor must be powered from an intrinsically safe source of power. This may be either:-
o
An intrinsically safe power supply, or,
o
A safe-area located, non-intrinsically safe power supply via the use of an appropriate
zener barrier.
The sensor must not be directly powered from a non-intrinsically safe power supply (i.e. without
the use of an intervening appropriate barrier).
Connections to and from this sensor must only be to equipment with compatible entity
parameters.
The installation of this sensor must be carried out by suitably trained and qualified personnel.
Certification and identification labels fixed to this sensor must not be damaged, removed or
covered before, during or after installation.
Modifications must not be made to any part of the sensor. As supplied, the unit is built to, and
complies with the standards against which it has been certified. Modifications to its construction
will render the unit incompatible with its certificate.
Complete and accurate records of the installation must be kept as part of the site dossier.
