Kistler-Morse KM L-Cell Bolt-On - Manual (Page 23)

Chapter 3. L-Cell Installation on Vertical Legs
3-9
Wiring Junction Boxes Together and to Signal Processor
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.
Figure 3-17. Inserting Shielded Interconnect
Cable through PG13.5 Fitting and Cap
PG13.5 Fitting
and Cap
Large Hole (typical)
Sealant
Shielded Cable
12
12
12
12
There are two versions of the junction box enclosure. Both versions have
four small holes for wiring L-Cells to the junction box, as described above.
In addition, the junction box has one or two large holes:
• One large hole for conduited installation — The large hole, which
accommodates a
3 /4” conduit fitting, is for wiring the junction box to
the other junction boxes and to the signal processor.
• Two large holes for non-conduited installation — The two large holes,
which are equipped with PG13.5 cable fittings, are for wiring the
junction box to the other junction boxes and to the signal processor.
KM requires the use of cable trays for non-conduited installations.
Notes
1. The procedure below assumes the conduit/cable tray has been
installed.
2. Seal all conduit fittings against water entry. Install drain holes at
conduit’s lowest elevation(s) to allow condensation to drain.
3. Use Belden™ 3-conductor shielded interconnect cable or
equivalent to wire junction boxes together and to the signal
processor. For lengths up to 1,000’ (305m) use 18-gauge Belden
8791 cable. For lengths from 1,000’ to 2,000’ (305m to 610m) use
16-gauge Belden 8618 cable.
4. When wiring cable to junction box terminals, strip back 3”
(76mm) of cable sheathing to expose the three conductor wires
and shield wire inside. Strip
1 /
4
” (6mm) of insulation from the end
of each of the conductor wires.
5. All wiring routed between junction boxes and signal processor
must be continuous (no splices).
1. Remove the junction box cover.
• Conduited installation — Install a conduit fitting in the large hole in
the bottom of the junction box.
• Non-conduited installation — See Figure 3-17. Spread a generous
bead of sealant around the sides of the PG13.5 cable fittings. Install
the fittings in the two large holes in the bottom of the junction box.