PG7000™ OPERATION AND MAINTENANCE MANUAL
© 1998-2008 DH Instruments, a Fluke Company
Page 184
10 and 20 kPa/kg Gas Piston-Cylinder Module
Figure 14.
10 and 20 kPa/kg Gas
Piston-Cylinder Module (Expanded View)
Place the piston-cylinder module upside down
on a clean stable surface (piston cap (2) down).
Using the sleeve nut tool (see Figure 16), remove
the sleeve nut (9). The sleeve nut tool is a
spanner that fits into the two holes on the
sleeve nut.
The sleeve nut for 10 and 20 kPa/kg modules has
a left hand thread so it is loosened by turning clockwise.
Remove the O-ring assembly (8). Then, being
sure to support the cylinder (7) so it doesn’t fall
out, turn over the remaining assembly so that
the piston cap (2) is up.
While firmly holding down the cap (2), use a 5 mm
Allen tool, to loosen the socket head cap
retaining screw (1). The cap retaining screw
will not fully disengage from the piston cap due
to the adjustment mass (3). Gently remove the
cap and screw from the assembly.
When installing the piston cap during
reassembly, remember to reinstall the adjustment
mass (3).
Remove the main module housing (4) by
sliding it upward leaving the piston-cylinder
assembly behind.
Step 6 applies only to 20 kPa/kg:
Reinstall the piston cap (2) directly onto the
piston head (6). Using the cap as a handle,
slide the piston out of the cylinder. Take care
not to cock the piston in the cylinder at the
point at which it leaves the cylinder.
Steps 7, 8, and 9 apply only to 10 kPa/kg:
Reinstall the piston cap (2) directly onto the
piston head (5).
Place the 10 kPa/kg piston insertion tool (see
Figure 15) on the work surface with the large
diameter down. DO NOT TOUCH the white
plastic centering ring of the insertion tool.
Holding the cylinder (7) to prevent it from falling
out, place the piston-cylinder assembly onto the
tool sliding the hollowed end of the piston (6)
onto the tool shaft. Carefully allow the cylinder
to drop down over the white plastic centering
ring. Holding the cylinder, gently remove the
piston (6) from the tool. Finally, remove the tool
from the cylinder.
In reassembly, the end of the cylinder marked
with the serial number must enter the main module
housing first.
The orientation of the piston on the cylinder is
important. The end of the cylinder that is marked with
the serial number should go into the sleeve and/or main
module housing first. The piston enters the end of the
cylinder that is marked with the serial number.
Installing the cylinder with the wrong orientation may
lead to out of tolerance measurements.
