888-2406-002
4-25
WARNING: Disconnect primary power prior to servicing.
Overall System Theory
To determine if a tap has failed (blown fuse), refer to the Diagnostics Display. For
Power Supply 1, Press [STATUS, D,A,A,D] This will show you the screen in Figure
4-14.
Figure 4-14
Power Supply Tap Status
4.5.2
Single Phase PA Power Supply
Refer to the Overall System Block Diagram in the schematic package for the
following discussion. The transmitter single phase AC inputs connect directly to
K1, the AC mains contactor. The transformer side of the contactor is wired in to
power transformers T1 via the 1A17TB1 terminal block on the front of the power
supply tray. T1 primary must be tapped for the proper AC input voltage. The
tapping chart can be found on the Overall System Block Diagram. The transformer
has one center tapped secondary with the center tap being the rectified DC output of
52Vdc. The DC output is filtered by L1, C1, and C15. Each of the transformer
secondary taps is connected to an SCR which is controlled by ON/OFF signals from
the PS Controller board via the Rectifier Board.
The secondary of T1 uses the unique tap switching design to give a small window of
coarse regulation (approximately 2Vdc change per tap) to compensate for AC line
variations.
4.5.2.1 Rectifier Board
The SCRs for the single phase supply are required to carry a much larger amount of
current than the 3-Phase counterparts and are therefore much larger. They are
mounted on large heatsinks on top of the transformers. The SCRs are used for the
tap switching as well as rectification of the AC voltage. Each transformer secondary
winding has 8 taps. Each of these taps have one SCR to ground. The secondary is
full wave rectified, which means that one SCR on each side of the center tap is used
for each voltage level. For example CR1 and CR5 will be active at the same time.
The other pairs are CR2 and CR6, CR3 and CR7 and CR4 and CR8. The Power
Supply Controller can turn on any pair of the SCRs at a given time. If the voltage is
not high enough at the DC output, the PS Controller can change the transformer
turns ratio by turning on a different SCR pair and therefore utilizing a different
secondary tap. The taps closest to the center will provide the least amount of
Summary of Contents for Platinum Z2 CD
Page 4: ...888 2406 002 WARNING Disconnect primary power prior to servicing ...
Page 6: ...888 2406 002 WARNING Disconnect primary power prior to servicing ...
Page 8: ...888 2406 002 WARNING Disconnect primary power prior to servicing ...
Page 10: ...888 2406 002 WARNING Disconnect primary power prior to servicing ...
Page 70: ...3 14 888 2406 002 WARNING Disconnect primary power prior to servicing Operator Guide ...
Page 130: ...4 60 888 2406 002 WARNING Disconnect primary power prior to servicing Overall System Theory ...
Page 194: ...6 38 888 2406 002 WARNING Disconnect primary power prior to servicing Troubleshooting ...
Page 196: ...7 2 888 2406 002 WARNING Disconnect primary power prior to servicing Parts List ...
