Harris Maxiva ULX, Technical Manual

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10/6/10 888-2629-200 2-5
WARNING: Disconnect primary power prior to servicing.
Section 2 Installation
Maxiva ULX COFDM Series
2.3 Installation Steps
Steps in the installation section are numbered in each section. As each step is
completed, the step number can be circled to indicate completion. This provides a quick
confidence check at the end of the procedure that no steps were skipped.
The primary
goal of each step is indicated by bold letters , with the rest of the paragraph being
support information.
NOTE:
In case of discrepancy between the connections listed in schematics versus infor-
mation given in this installation section, the wiring information in the schematics
should be considered the most accurate.
All connections listed in this section
should be verified with the schematics before initial turn on .
When performing the installation, after the transmitter cabinet(s) are in place, plan to
run the transmitter output transmission lines first, then the liquid cooling system
plumbing lines, and finally the electrical conduit runs. If air handling duct work is to be
installed, plan all of the RF, plumbing and conduit runs to leave room for the duct work.
The reason for this installation order is that rigid coax runs must be installed with
minimum elbows. If the RF runs encounter obstacles such as liquid coolant lines,
conduit, and duct work more elbows are required. The RF lines should have a minimum
number of elbows for best performance.
The liquid cooling system plumbing should installed next. Avoid excessive 45 and 90
degree elbows, especially back to back elbows as they will restrict the flow of the liquid
coolant and increase the dynamic head pressure. Heavy duty hose can be used instead of
copper line, hose is much easier to install and can be installed last, as long as large
radius turns are used and sharp bends of the hoses are avoided. Hose must be supported
more frequently than copper. Good support is required to avoid sagging of the hose,
because it can trap liquid when the system is drained, stress the hose at the support
points, and, if the sagging is deep enough, can cause flow restriction due to the hose
collapsing at the support points.
NOTE:
Plumbing elbows or 45
o
bends tend to produce turbulence in liquid coolant lines.
Avoid use of back to back elbows or bends. As a rule of thumb, maintain 10 pipe
diameters of straight pipe either side of elbows, bends, valves or flow meters.
Where feasible the electrical installation should be performed last since it is the easiest
to run, and is most forgiving as to the number of elbows used. It can more easily be
routed around obstacles.