Harris Platinum Z2 CD, Руководство пользователя

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WARNING: Disconnect primary power prior to servicing.
Overall System Theory
4.4.1.2 3-Phase Power Supply
The Z2 transmitter uses a single main power transformers whose DC outputs are
combined through large inductive chokes. Figure 4-8 shows a simplified diagram of
the PA power supply transformer. For additional redundancy, the Z2 can be
configured with an optional second supply (See Appendix A, Z2 Redundancy
Package). The transformer has a 3 wire extended DELTA or 4 wire extended WYE
primary (depending on your AC input configuration) and two secondaries labeled A
nd B which are always WYE, with the center tap being the output. The outputs of
the 2 secondaries are combined through chokes and filtered by a single 120,000uF
capacitor. The combination of the extended primary windings and the dual
secondaries (each at a different phase angle) results in an output ripple frequency of
600/720Hz for 50/60Hz input. Each of the secondary windings has 4 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 12 SCRs per secondary, but only 3 SCRs will be
activated at any one time providing the ability to regulate the output DC voltage by
changing the transformer turns ratio.The 4 secondary taps allow DC outputs of 48,
50, 52 and 54Vdc (with nominal AC input voltage). The tap switching is controlled
by the Power Supply Controller board. The transformer assembly is designated PS1.
PS1 provides power for all 8 PAs. For the dual supply configuration there are 2 PS
Controllers and each supply feeds 1/2 of the PAs.
Figure 4-8
Simplified 3-Phase Power Supply