Harris Platinum Z2 CD, Manual

Page: 88 / 196

4-18 888-2406-002
WARNING: Disconnect primary power prior to servicing.
Overall System Theory
4.4.1.3 Single Phase Power Supply
The transmitter has one power supply for the standard Z2 and 2 power supplies for
the Z2R (Redundant Package). These are designated PS1 (and PS2 for the Z2R).
Figure 4-10 shows the placement of each of the power supplies and connection
points for installation or removal of the supplies.
Figure 4-10
Power Supply Locations for Z2 and Z2R
Refer to the Overall System Block Diagram in the schematic package and Figure 4-
11 for the following discussion. The power supply consists of a power transformer
with a single center tapped secondary. The Z2R (Redundancy Package) is
configured with a second supply and second PS Controller for redundancy. The
center tap is the 52Vdc output and is filtered by a large choke and 3 large filter
capacitors. The single phase supply is full wave rectified giving a ripple frequency
of 120Hz and therefore requires more filtering than the 3-Phase supply.
The secondary winding has 8 output taps, each of which are connected through an
SCR to ground. The SCRs act as both tap switches, activating the tap which gives
the appropriate DC voltage output, and as rectifiers. This gives a total of 8 SCRs,
but only 2 SCRs will be activated at any one time providing the ability to regulate
the output DC voltage by changing the transformer turns ratio. The 8 secondary taps
allow DC outputs of 48, 50, 52 and 54Vdc. The tap switching is controlled by the
Power Supply Controller board. The transformer assembly is designated PS1 (with
the optional second supply called PS2). PS1 provides power for all 8 PAs. For the
dual supply configuration each supply feeds 1/2 of the PAs.
Standard Z2, PS1
Z2R (Redundant) PS1 and PS2