Atest Gaz Alpa EcoTerm XT, Руководство пользователя

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9.2 Set-up
9.2.1 Location of detectors
The location of detectors should be determined by the designer of the system, taking into consideration the
following principles:
methane detectors should be installed less than 30 cm below the topmost point of the facility
roof. Methane is lighter than air and tends to migrate upwards,
gas detectors should be installed at locations where accumulation of gases is the most probable
due to structural properties of the facility (e.g. any part of the facility is separated from the
remaining space by means of structural components),
the detectors should not be exposed to the direct impact of water or other chemical substances
(e.g. cleaning agents during the facility cleaning), direct impact of sunlight, rain, water,
the detector should be protected against damaging mechanical exposures,
the detector location should enable conducting checks and the sensor adjustments, as well as its
replacement or disconnection.
9.2.2 Installation
Electrical installation of the detectors may only be performed by persons having appropriate qualifications
or acting in agreement or under the supervision of the manufacturer. The electrical installation should be
performed in accordance with the design.
The electrical installation of the detectors should be performed in accordance with the general
principles of performing measurement and control systems 3 . Cables should be installed in a way
protecting them from damage. Installation in cable ducts is required.
All activities related to the connection of the detectors and other components of the system
must be made while the power supply to the control unit is switched off. Although the
power supply to the gas detection system is switched off, there is a possibility that the
source of dangerous voltage may be another system (e.g. a ventilation system using pin
outputs).
Or making connections, it is possible to use three-wire cables e.g. of the YTKSY, OMY, LiYY type
(bus). For connecting the EcoWent XT detector, it is necessary to apply a four-wire conductor. The
selection of a specific cable type depends on the designer and should take into account the
conditions in the place in which the gas detection system operates. The maximum lengths of the
wires connecting the detector with the control unit for a given cross-section of cable wire are
given in Appendix [3].
When selecting the cable, it is necessary to pay attention to voltage drops on the lines.
The power line should be designed in such a way that, at the lowest expected voltage of the
line power supply, the voltage "seen" on the detector terminals does not drop below the
permissible value (see section 10).
The spring clips of the terminal strip are released by pressing the button with a screwdriver.
3 Control and measurement instruments
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User Manual: POD-044-ENG R01