Kistler-Morse KM L-Cell Bolt-On - Manual (Page 32)

Chapter 4. L-Cell Installation on Horizontal Beams
4-7
Note
If the following occurs while tightening screws, check L-Cell resistance
using a DMM (described in Problem 1 in Chapter 6, 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).
8. To complete installation, ensure that:
• Both 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.
9. Repeat Steps 2 through 8 to install L-Cell B on the other side of the web.
10. Prior to installing the environmental covers, ensure the mating surfaces on
the web are free of dirt and grease. Reclean if necessary, being careful not
to remove the rust inhibitor on the bare metal.
11. See Figure 4-11. Peel the protective backing from the double-sided tape on
the environmental cover’s inside flange.
A. Align the cover over the L-Cell, with the cable through the cover’s exit
channel. Press the cover onto the mounting surface.
B. Spread a 1 / 8 ” (3.2mm) bead of sealant around the joint between the
cover and mounting surface. Add extra sealant to the cable exit channel
and between cable and skirt.
C. Use your finger to smooth the sealant around all edges and joints,
eliminating areas where moisture may pool, especially along the top
edge. Verify the sealant forms a continuous, watertight seal.
D. Repeat Step 11 for L-Cell B.
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.
12. If you created any holes that go completely through the web, spread
sealant (Sikaflex 1A polyurethane sealant or Dow Corning RTV 739 or RTV
738) over the open holes. Use your finger to press sealant into each hole.
Cable Exit Channel Tape
1/8” (3.2mm)
Bead
All-Around
(wipe smooth)
Tape
Tape
Figure 4-11. Environmental Cover