WIKA TR12-M - Handbuch (Seite 20)

GB
7. Information on mounting and operation in hazardous areas
11419904.02 09/2013 GB/D
WIKA operating instructions models TR12, TC12 (Ex d) 20
■ The responsibility for classification of zones lies with the plant operator and not the
manufacturer/supplier of the equipment.
■ The plant operator guarantees, and is solely responsible, that all thermometers in use
are identifiable with respect to all safety-relevant characteristics. Damaged thermometers
may not be used.
■ For the installation of the thermometer, only components (e.g. cables, cable glands, etc.)
permitted for “flameproof” may be used.
■ For earthing the conductive screen, follow the specifications of EN/IEC 60079-14.
■ When using a transmitter/digital display, note and follow:
- The contents of these operating instructions and those of the transmitter/digital display
- The relevant regulations for installation and use of electrical systems
- The regulation and guidelines regarding explosion protection
■ The certified flameproof thermometers should only be fitted to housing- or connection
heads certified with a “flameproof” ignition protection type.
■ Certified and listed field cases (variant 3) should only be fitted and installed by a
specialist trained to the latest technology.
■ For fitting, the permitted flameproof joints for electrical equipment for gas hazardous
areas are contained in EN, IEC 60079-1. Flameproof joints (section 5.3) for parallel
threads (in accordance with table 3), must be ≥ 5 mm for housing volumes < 100 cm³
and ≥ 8 mm for housing volumes > 100 cm³. There must be ≥ 5 threads engaged.
Flameprooof joints (section 5.3) for tapered threads (in accordance with table 3), must
have ≥ 5 available threads on each part. There must be ≥ 3.5 threads engaged.
These specifications for flameproof joints must be adhered to, without fail, when fitting
and during operation.
■ The direct threaded connection of the thermometer to the connection head or housing
must not be twisted or opened. Any alignment of the housing may only be made using
the optional “nipple-union-nipple” neck tube.
■ The temperature resistance of the connecting cable must match the permissible
operating temperature of the housing.
For ambient temperatures above 60 °C, heat-resistant connecting cable must be used.
■ No batteries may be built in to the flameproof housing.
■ No capacitor may be fitted within the flameproof enclosure that has a residual energy of
≥0.02 mJ at the end of the time required to open the housing. The housing must not be
opened during operation. After the power supply has been switched off, a waiting time of
2 minutes must be observed before the housing is opened.
■ Mounting within metallic enclosures:
The housing must be grounded against electromagnetic fields and electrostatic
discharge. It does not have to be connected separately to the equipotential bonding
system. It is sufficient if the metallic thermowell has a solid and secured contact with the
metallic vessel or its structural components or pipelines, so long as these components
are connected to the equipotential bonding system.