Dresser Masoneilan SVI II AP, Инструкция по эксплуатации

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DRAFT 6/8/10
29
Connecting the Tubing and Air
Installation and Set
Connecting the Tubing and Air Supply
The last step in hardware installation for the SVI II AP is to connect the air supply to the
positioner. This section describes the process for connecting the tubing and air supply to
a single and double acting positioner.
WARNING
Isolate the valve from the process and disconnect air tubing
from the positioner. Disconnect air fully to avoid injury or
process damage.
1. Install the tubing to the air supply port ( S

).
2. For a single acting actuator - pipe the outbound air from the output pressure port (

I
)
to the actuator.
3. For a double acting actuator - pipe output pressure port one (

I
) for one side of the
actuator and output pressure port two (

II
) for the other side of the actuator.
4. Air supply:
q
Supply pressure for single acting SVI II AP:
20 -100 psi (1.4 - 6.9 bar) (138 - 690 kPa)
q
Supply pressure for double acting SVI II AP:
25 - 150 psi (1.73 - 10.4 bar) (0 - 1035 kPa)
q
Minimum tubing diameter 1⁄4" (6mmx4mm)
NOTE
The SVI II AP Digital Positioner is designed to operate with
clean, dry, oil-free, instrument grade air to ANSI-ISA-57.3
1975 (R1981) or ISA-S7.3-1975 (R1981) or with a sweet
natural gas supply (SVI II AP models SVI II AP-2 through SVI
II AP-3).
CAUTION
Do not use pipe thread sealant tape on pneumatic fittings. It
may shred into small particles that can cause instrument
malfunction.
Table 6 Air Supply Requirements
Dew Point At least 18° F (10° C) below minimum anticipated ambient temperature
Particulate Matter Filtered to 5 microns
Oil Content Less than 1 ppm w/w
Contaminants Free of all corrosive contaminants