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AVID SmartCal valve positioner
Installation & operating instructions
Appendix E - General maintenance standard flow
The positioner’s onboard filter should be replaced regularly. See diagram for location of the filter.
Note
: The following instructions are for Standard flow. For High flow please contact the factory.
Important
: The positioner’s onboard filter is not a substitute for normal instrument air preparation.
Supply air to the positioner should conform to ISA Standard S7.3 - Quality for Instrument Air.
Important
: The filter’s original color is chalk white. If the filter is discolored, its replacement
should be performed more often. A discolored filter may also indicate the need for an evaluation
of the air-supply quality. A filter/regulator with a 5 micron or better element, just prior to the
positioner, is recommended.
Spool valve
In favorable conditions (i.e. high quality supply air, healthy actuator) there will be minimal if any
maintenance necessary on the spool valve.
If unfavorable conditions exist (i.e. Poor supply air quality or if lubrication and sediment from
the actuator is being exhausted through the spool valve) it may become necessary to clean the
spool valve to avoid operational failures due to valve sticking and to maintain optimum positioner
performance.
To clean the spool valve, the spool piece needs to be removed (see diagram below). Prior to
removing the spool, make sure the positioner is out of service and all air pressure has been bled-
off the positioner and the actuator.
The spool piece and sleeve can be cleaned using any non-chlorinated cleaning solvent (such as
Stoddard solution or volatile mineral spirits).
To clean the spool, use a clean lint free cloth. To clean the I.D. of the sleeve, a polyester, lint free
clean room swab is recommended. These items can be obtained from most industrial supply
companies or catalogs.
Important:
Do not use an abrasive cleaner on the spool or sleeve. Never buff the spool or sleeve
or use crocus cloth, and never attempt to remove the sharp edges from the spool lands. These
practices will damage the spool assembly and will affect the fit and action of the spool sleeve
assembly.
Important:
The spool and sleeve assembly is sold as a precision matched set. Spools are not
interchangeable. To prevent mix-ups it is recommended that only one assembly be cleaned at a
time.
Important:
After cleaning, insert the spool, into the sleeve, gently. Insert straight with a slight
rotating motion. Do not cock the spool. Make sure the spool spins and moves freely. After the
spool valve is cleaned and reassembled it is recommended that the positioner be recalibrated.
PR - 10027
SmartCal
manifold filter
holder/W O-ring
MS - 10222
SmartCal filter
