VAC V200 Series, Инструкция по установке, эксплуатации и обслуживанию

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V200 POSITIONER
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1.1 Air quality recommendations
Poor air quality is one of the main causes of
premature functional problems with pneumatic
and electropneumatic equipment. The pilot
valve and IP converter are precision instru-
ments, and are therefore the most sensitive
parts of the positioner.
a)
Water in the supply air is a natural occur-
rence. This happens when air is compressed.
The compression heats the air and the natural
degree of water in the air can remain as mois-
ture. When the air cools in pipes etc.
the moisture condenses and becomes liquid
water. Large quantities can build and some-
times flood small water separators. This ex -
cess water will eventually reach the control
valve and positioner. This can cause corrosion
damage to the IP converter, causing the
unit to malfunction.
We strongly recommend the use of water
separators with adequate capacity. Coales-
ing filters from a reputable manufacturer is an
inexpensive way to help prevent unit malfunc-
tions or failures, and add life to the product.
These filters remove particles and moisture
from air lines.
b) Oil in the supply air usually is from the main
compressor. Oil can clog the small nozzles
and disturb the flapper in the IP converter. It
can also cause the spool to “drag” within the
pilot valve. The result is poor control or in the
worst case, failure.
c) Particles in the air usually occur because
of corrosion. Dirt and particles can block the
small nozzles of the IP converter.
They can also cause the pilot valve to mal-
function. The unit may completely fail.
To ensure normal operational safety with VAC
positioner products, we recommend that a wa-
ter separator and a <80 micrometer filter are
mounted as close to the product as possible.
If large amounts of oil are present an oil sepa-
rator should be installed as well.
To further increase operational safety, we rec-
ommend that the working air is clean, dry and
free of moisture, water, oil, particles and other
contaminants, in accordance with the
Standard ANSI/ISA– 7.0.01– 1996
CAUTION: Beware of moving parts
when positioner is operated!
CAUTION: Beware of parts with
live voltage!
A voltage, which is normally not
dangerous, is supplied to the
positioner.
Avoid touching live parts and bare
wires as well as short circuiting live
parts and the housing.
CAUTION: Do not dismantle a
pressurized positioner!
Dismantling a pressurized positioner
will result in uncontrolled pressure
release. Always isolate the relevant
part of the pipeline. Release the pres-
sure from the positioner and the pip-
ing. Failure to do this may result in
damage or personal injury.
CAUTION: Do not exceed the
positioner performance limitations!
Exceeding the limitations marked on
the positioner may cause damage to
the positioner, actuator and valve.
Damage or personal injury may result.
1.2 Safety Instructions
1 INTRODUCTION