Kistler-Morse KM L-Cell Bolt-On - Manual (Page 19)

Chapter 3. L-Cell Installation on Vertical Legs
3-5
5. Fig. 3-12. Using the T-handle driver, slowly tighten the S2 screw. While
turning the T-handle driver, monitor the Test Meter carefully.
If the voltage goes outside the range -200 mVto +200 mV while tighten-
ing, 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 leg. Remove burrs and surface roughness (refer to
Surface Preparation for removing surface roughness). Repeat Steps
1 through 5.
• 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 6.
6. Repeat Step 5 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 combina-
tion 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.
Note
If the following two situations occur while tightening screws, check
L-Cell resistance using a DMM (described in Appendix E,
Troubleshooting):
• Voltage does not change or changes less than 25 mV as you turn a
screw, or
• Voltage changes randomly as you turn a screw (i.e., not in a
consistent direction).
7. To complete installation, ensure that:
• All three screws are tightened until the T-handle driver flexes in
torsion, 1 /
4
turn past the point where the screw stops turning, with
this flexing procedure repeated several times to ensure the screw is
tight, and
• Voltage is in the range -200 to +200 mV.
CAUTION
Only use Sikaflex 1A
polyurethane sealant or
Dow Corning RTV 739
or RTV 738. Other
sealants may contain
acetic acid, which is
harmful to sensors and
electronics.
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 all three
screws are tight, the
voltage must be in the
range -200 to +200 mV.
Follow the procedure in
Steps 5 through 7 to
achieve this goal.
Figure 3-12. 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
S2
#6-32 Cap Screw
S3 #6-32 Cap Screw