Routing and Installing Fibre Bundles
to Pulser Boxes
Once a plane has been raised, the LI
fibres need to be uncoiled and securely routed to the appropriate pulser
box, (each pulser box serves one side of 64 planes). The mine crew will
be trained to undertake this task and also to connect the 20-way connectors
to the pulser box. (Some mine crew, esp. Irene, Dan have had a lot of experience
at installing fibres to MUX boxes and so should also be able to install
fibres to pulser boxes.)
Specifically, they will be following
these guidelines:
Routing
-
Each fibre bundle should be routed via
the cable trays to the appropriate pulser box. The first 32 planes in a
set of 64 will be routed to the southern most side of the rack and the
second 32 to the northern most side.
-
The fibre bundles coming from the lower
half of the detector are to be routed to the appropriate hole in the floor
next the rack. Take special care when routing these fibre bundles as often
there are sharp edges around the holes. These should be taped before any
installation is attempted.
-
Velcro tape should be used to secure
the fibres in place in the cable trays.
-
It is very important to watch out for
tight bends in the individual fibre ends (which plug into the LIMs) near
where the fibre bundle leaves the detector. Use cable ties or velcro to
ensure that all of the fibres are safe.
This photo shows how the bundles
are secured as they come from the planes. A single strip of velcro tape
is enough to force the bundle to run along the cable tray to the pulser
box.
This rotationally challenged shot
shows the routing of 64 fibre bundles to a pulser box. Note that the fibre
bundles come from 4 different directions, and are connected to the corresponding
4 quadrants on the back of the box. The blacked out connector ends that
can be seen in this shot are actually coming through the floor from the
lower level.
Also look at the fibre bundles
as they come from the planes to ensure that none of the individual fibres
are dangerously close to the minimum bend radius. Try to arrange the bundles
such that all fibres have as much slack as possible.
Installing
-
Use a couple of washers on each screw.
(The screws are a standard size which is a little too long for the pulser
box connectors.)
-
Grease must be used when installing
fibre bundles, to help reduce the transmission differences observed over
a connector.
-
In place of rubber bands to light tight
the connectors, a strip of black insulation tape should be used
-
The installation date for each fibre
bundle to the pulser boxes must be recorded. Whoever installs the
fibre bundles will also fill in the installation date for each plane+side
on a form which can then be entered into a database somewhere (to be done
by Robert Hatcher, Phil Adamson...?).
Also see "Attaching
Fibre Bundles to Pulser Boxes" for more tips on installation
Also need to install PIN fibre bundles
and trigger PMT fibres for each box, see separate page
for instructions.
Back to main
LI installation page