7
Fig.2-3 The “Control” PCB and optic devices in the remote AATU unit.
Push 2-3cm (one inch) more cable length into the cable gland (so that not to stretch the inside cable length after
having it connected to the optic devices (fig.2-2,a-b) and tighten the cable-gland cap using a wrench sized 22mm
(7/8”). Use only enough force while tightening in order that the cable be tight and could not slip out when pulled
occasionally (do not overdo it since a cable-gland destruction is likely).
C A U T I O N
The optic cable ends are supplied readily bared and prepared for installation.
Nevertheless, check on each cable end whether the external sheath has been
removed about 100mm (four inches), in order to move apart both fiber cores to both
optic devices. In addition, each fiber face must be cut as smooth as possible and in
a vertical section. Check whether the cut surface is clean of contamination and
lucid.
Should you need to bare the cable once more again, first peel off the external cable sheath about 10-12cm (four
inches) from the end. Be careful not to injure the cores under the sheath. Then cut small lengths (2-5mm, 0.1-0.2”) off
each core end in order to expose a clean and lucid surface of the transparent light-guiding plastic fiber. Use a clean,
sharp and smooth-surface knife. Keep track to make a precisely vertical section. The light loss and reflections
depend strongly on this operation quality. To improve the cut performance we recommend to pre-heat the knife blade
(to about 70-80 deg.C or 160-175F). Be careful not to contaminate the blade while heating and not to over-heat it.
Loose the split-socket-knurled nut of either optic device slightly (fig.2-3). Then push either core into the split socket,
shove the core against the stop, and tighten carefully its knurled nut by hand. Keep track that no foreign matter is
caught into the optic device aperture since this would obstruct the light beam.
Use only enough force while tightening in order that the cable be tight and could not slip out when pulled
occasionally (do not overdo in order not to damage the plastic case or the optic device). Repeat the same operation
with the second cable core and the other optic device. As mentioned above, identification of the channels transmit
and receive will be made at first power on – see S.2-4(c).
e) Unscrew the metal cable-gland cap (marked “24VAC/3A” on the bottom panel (see fig.2-1,f) and thread it over the
bared end of the four-core screened power-supply cable in such a direction as to be able to screw it onto the same
place later. Take out the plastic insert from the cable gland housing. Thread the insert over the cable end in such a
direction, that its split end be next to the metal cap, and the slender end – to the cable bared tag (see fig.2-4).
