Kistler-Morse KM L-Cell Bolt-On - Manual (Page 31)

Chapter 4. L-Cell Installation on Horizontal Beams
4-6
CAUTION
Do not install L-Cells in the rain.
Do not trap moisture under the environmental cover.
1. Mark two small pieces of masking tape ‘A.’ Place one piece of tape on the
plastic body of a L-Cell and one piece near the end of the L-Cell cable.
Repeat for the other L-Cell, labeling it ‘B.’
2. Wipe down a 5 in. X 2 1 /4 in. (127mm x57mm) surface, centered on the
template mounting hole, with degreaser. This cleans the bare metal and
adjacent mounting surface for the environmental cover. See Fig 4-10.
3. Apply a thin coat of K-M rust inhibitor to the bare metal surface for
L-Cell A.
Note
Do not apply rust inhibitor beyond this area, or the environmental cover
will not adhere properly.
4. Connect the L-Cell’s red, black, and white wires to the corresponding
terminals on the K-M Test Meter. Turn on the power to the Meter and set
the Simulate/Test switch to the Test position.
Note
If a KM Test Meter is not available, refer to Appendix G, Alternate
Method for Checking Output, before proceeding with Step 5.
5. With the cable end down, align L-Cell A with the mounting holes, ensuring
that the top of L-Cell A faces toward the vessel load point. Fasten the
L-Cell loosely to the web using the three socket head cap screws (and
sealant). Do not tighten the screws. If the voltage goes outside the range
-200 to +200 mV, immediately loosen the screw(s).
6. Using the T-handle driver, slowly tighten screw #S2. While turning the
T-handle driver, monitor the Test Meter carefully.
If the voltage goes outside the range -200 to +200 mV while tightening,
stop immediately and evaluate the following:
• If the voltage jumped outside the range -200 to +200 mV, it may indicate
a burr or rough surface. Remove the screws holding the L-Cell to the
web. Remove burrs and surface roughness (refer to Surface Prepara-
tion for removing surface roughness). Repeat Steps 1 through 6.
• If the voltage gradually moved outside the range -200 to +200 mV,
slowly loosen the screw until the voltage is within range again and
proceed to Step 7.
7. Repeat Step 6 for screws S1 and S3. If the voltage is outside the range -200
to +200 mV, attempt to bring the reading within range by loosening the
screw being torqued, tightening the other screw, or some combination of
loosening and tightening. If you have difficulty staying within the range,
try turning each screw
1 / 4 turn at a time until both screws are tightened.
Mounting L-Cell
CAUTION
For proper installation,
tighten each screw until
the T-handle driver flexes
in torsion
1 /4 turn past
the point where the screw
stops turning. Repeat this
flexing procedure several
times to ensure the screw
is tight. When both
screws are tight, the
voltage must be in the
range -200 to +200 mV.
Follow the procedure in
Steps 6 through 8 to
achieve this goal.
Figure 4-10. L-Cell Mounting
Notes:
1. Do not apply rust inhibitor outside the
2.50” (63.5mm) diameter bare metal, or
environmental cover will not adhere
properly.
2. Place small amount of sealant on each
screw before mounting L-Cell.
Apply Rust
Inhibitor to
2.50” (63.5mm)
diameter bare
metal surface
Degrease
4.50” (114mm)
diameter surface
S1
#6-32 Cap Screw
S3
S2