JBL CONTROL 24C Owner's Manual page 12

The strain relief can be tightened in two ways, choose whichever is best for your
application:
a) Tightening onto plenum cable or bare wire-- Slide the wiring through the strain
relief fitting on the terminal cover plate. In the case of bare wire and plenum cable it is
often possible to provide acceptable strain relief force by simply tightening the screws
holding the sliding strain relief onto the terminal cover plate. To achieve a tight fit, use
a clamping mechanism (such as slipjoint pliers) to hold the strain relief pieces together
while tightening the hold-down screws.
It is optional to reinsert the horizontal screw that was previously removed and to tighten
the two horizontal screws, clamping the wire securely between them.
Figure 14:
Tightening Fitting
Onto Plenum Cable (shown)
Or Bare Wire
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