SMAR LD292, Руководство по эксплуатации, техническому обслуживанию и инструкциям

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Section 1
1.1
INSTALLATION
General
NOTE
The installation carried out in hazardous areas should follow the recommendations of the
IEC60079-14 standard.
The overall accuracy of level or pressure measurement depends on several variables. Although the
transmitter has an outstanding performance, proper installation is essential to maximize its
performance.
Among all factors, which may affect transmitter accuracy, environmental conditions are the most
difficult to control. There are, however, ways of reducing the effects of temperature, humidity and
vibration.
The
LD292 has a built-in temperature sensor to compensate for temperature variations. At the
factory, each transmitter is submitted to a temperature cycle process, and the characteristics under
different pressures and temperatures are recorded in the transmitter memory. At the field, this
feature minimizes the temperature variation effect.
Mounting
Locating the transmitter in areas protected from extreme environmental changes can minimize
temperature fluctuation effects.
The transmitter should be installed in such a way as to avoid, as much as possible, direct exposure
to the sun or any source of irradiated heat. Installation close to lines and vessels with high
temperatures should also be avoided. Use longer sections of impulse piping between tap and
transmitter whenever the process fluid is at high temperatures. Use of sunshades or heat shields to
protect the transmitter from external heat sources should be considered.
Proper winterization (freeze protection) should be employed to prevent freezing within the
measuring chamber, since this will result in an inoperative transmitter and could even damage the
cell.
Although the transmitter is virtually insensitive to vibration, installation close to pumps, turbines or
other vibrating equipment should be avoided.
The transmitter has been designed to be both rugged and lightweight at the same time. This makes
its mounting easier; mounting positions are shown in Figures 1.1 and 1.2.
Should the process fluid contain solids in suspension, install valves or rod-out fittings at regular
intervals to clean out the pipes.
The pipes should be internally cleaned by using steam or compressed air, or by draining the line
with the process fluid, before such lines are connected to the transmitter (blow-down).
NOTE
When installing or storing the level transmitter, the diaphragm must be protected to avoid
scratching-denting or perforation of its surface.