IPF
Page A3
Note that not all gauges, valves, and differential
pressure indicators (for filter service monitoring) are
not shown.
It is recommended that filters with integral service life
indicators or differential pressure indicators be used
to help ensure proper servicing. Use redundancy in
a filtering scheme to preclude any necessity for
shutdown during servicing.
Note that the systems depicted in the figures differ in
the method used to remove water. The use of a
desiccant dryer, as in figure A2, requires both
upstream and downstream filtration to prevent oil
contamination of the desiccant, as well as to prevent
desiccant fines from introducing new contamination.
ISA Specifications
The Instrument Society of America standard ISA-
S73, 1975 (ANSI MC11.1-1975) comprises the air
quality requirements for instrument-grade air for use
in pneumatic applications.
Although ISA specifications call for particle size not
to exceed 3 microns, and oil content not to exceed 1
ppm, coalescing filters are readily available that
remove particles down to sub-micron sizes (as small
as 0.01 micron), while also removing oil to below
0.01 ppm.
Moore Industries filters that exceed ISA specifica-
tions provide very inexpensive protection. Contact
your Sales Representative for more information.
