SMAR HART FY500, Installation Operation & Maintenance

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Section 1 - Installation
1.13
Pneumatic Connections
The FY500 requires instrument air quality, following the best practices for pneumatic installations.
Consult the American National Standard
“Quality Standard for Instrument Air” (ANSI/ISA S7.0.01 –
1996) for detailed information. Instrument air shall the following characteristics:
Dew point 10ºC below minimum instrument temperature.
Size of particles 40 µm (maximum).
Oil content 1 ppm w/w (maximum).
Contaminants Free of corrosive contaminants and hazardous gases.
The instrument air quality shall be superior to that of industrial compressed air. Humidity, suspended
particles and oil contamination, even lubricating oil, may impair the instrument operation, either
temporarily or permanently in case of internal parts wearing.
The mentioned standard recommends to place the compressor intake in an environment free from
process spills, contaminants, and to use adequate filters. Also, the compressors must be of non-
lubricated type to prevent the present of lubrificants. When using lubricated compressors, the plant
must have resources to remove the lubricant from the instrument air supplied.
The supply pressure varies from 2 bar (30 psi) minimum, to 10.3
bar (150 psi) maximum. The
FY500 requires sufficient supply pressure to stroke the actuator to each end of its travel.
Maximum allowable air supply pressure to the positioner must not exceed 10.3 bar (150 psi). For
actuator pressure refer to the appropriate actuator instruction manual.
WARNING
•
Never exceed maximum supply pressure. Injury personnel or damage to the
equipment may result.
•
Supply pressure to positioner should not exceed actuator maximum pressure rating.
•
Blow out all piping before connections are made to prevent dirt, chips, or debris to
entering to the positioner.
•
Use a pipe sealant sparingly and only on male threads. It is not recommended a
sealing tape on pneumatic connections.
The positioner vents the supply medium into the surrounding atmosphere through holes located in
the positioner vent cover, as shown in figure 1.18. The positioner does not have an external vent
connection. Do not restrict the vent opening. Restricting the vent opening can produce a pressure
buildup in the positioner valve spool and degrade positioner performance. Ensure that the housing
vent opening is open and free of debris to prevent pressure buildup under the cover.
Connect the power supply to the 1/4 NPT IN connection on the positioner. The output connections
1/4 NPT OUT1 and OUT2 must be connected to the actuator. For best response times use tubing of
3/8- inch minimum size. See figure 1.18.
WARNING
When the input current is removed, the FY500 OUT1 should drop to zero and OUT2
register full pressure.
When using a positioner on a single acting actuator, close OUT2 and connect OUT1 to the actuator
pneumatic input.
When using a positioner on a double acting actuator, connect OUT1 and OUT2 to the appropriate
actuator pneumatic input. When the input current is removed, the FY500 OUT1 should drop to zero
and OUT2 register full pressure.