3. INSTALLATION
Page 37
© 2007 DH Instruments, a Fluke Company
Verify the level position of the AMH top plate in both directions using a level. Also verify
the indication of the built-in level on the top plate. Adjust the top plate resting position or
the AMH adjustable feet to level the top plate. The bubble level is adjusted initially at DHI
but may shift during shipment. Adjust the bubble level if needed to match the separate
level indication so that the built-in level can be used for future leveling.
Place the reference gas cylinder onto
the balance, passing the cylinder
support legs through the holes in the
top plate.
Recheck the distance between the
reference gas cylinder and the draft
enclosure wall using the loop alignment
tool as described in Section 3.3.11.
Visually check the position of the
reference gas cylinder assembly on the
balance in relation to the AMH top
plate. Through the center hole in the
top plate the feet of the cylinder support
can be seen resting on the balance
mass tray. The rear left foot should be
centered in a conical hole in the mass
tray. The foot on the right should slide
into the bottom of the straight groove of
the right support on the mass tray. The
front left foot will simply rest on a flat
support. All three legs of the cylinder
support should pass through the top
plate without contact and appear
centered in the holes in the plate.
Leaving the balance in place, make
small movements in the AMH-
GFS2102 base postion in order to
ensure clearance of the reference gas
cylinder legs and engage the cylinder
support feet as described above.
Figure 23.
Reference Gas Cylinder resting on
balance. AMH top plate installed; reference mass plate
uninstalled.
Figure 24.
View of cylinder support legs
through AMH top plate.
Using the GFS Tools software, set the AMH to the Zero position (See Section 4.2.2).
Adjust the three legs of the AMH evenly to raise or lower the AMH over the balance so
that the legs of the cylinder assembly are very close to but not touching the balance
mass tray
Exercise (cycle) the AMH platform (See Section 4.2.2). While the AMH is in motion the
reference gas cylinder should remain vertical with only very slight or no lateral motion.
Also, the feet of the reference gas cylinder support should set down on each cycle into
the center of the conical hole and straight groove supports on the balance tray without
much lateral sliding into place. The flat support is purposfully a large target to account for
any other alignment issues.
Use the AMH to set the reference gas cylinder to rest on the balance (See Section 4.2.2).
Close the doors of the draft enclosure. Using GFS Tools software, view the GFS balance
output. (See Section 4.2.1) The mass of the reference gas cylinder should be displayed
and should stabilize to well within 1 mg (0.001 g). If the indicated mass appears
unstable, the reference gas cylinder may be making contact with the AMH plate and
further adjustments are needed.
Open the doors of the draft enclosure. Remove the reference gas cylinder from the
balance and AMH and place it aside. Remove the top plate of the AMH and place it