Harris ATLAS ANALOGUE, Руководство пользователя

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7/26/05 888-2523-001 1-9
WARNING: Disconnect primary power prior to servicing.
Section 1 Introduction
ATLAS Analogue
1.2.5 Transmitter Power Supplies
The control system in the transmitter is powered by two low voltage power supplies
(LVPS).
An autotransformer provides 260VAC to each PA module’s integrated power supply.
There it is rectified to 350VDC then applied to an array of DC/DC converters.
Depending on the channel frequency, the DC/DC converter’s output is appoximately
26Vdc - 29Vdc (28V typical) drain voltage.
1.2.6 Cooling System
The Atlas Analogue transmitter uses a 50/50 glycol liquid cooling system to remove the
majority of the heat away from the transmitter but also has cabinet flushing fans to
remove residual cabinet heat. A simplified block diagram of the liquid cooling system is
shown in Figure 1-6. A simplified diagram of the liquid cooling system inside the
transmitter cabinet is shown in Figure 1-7. The cooling system basically consists of:
a.
Cooling System Control Panel
b.
Pump Module
c.
Heat Exchanger
d.
Transmitter Cold Plates
1.2.6.1 Cooling System Control Panel
The cooling system control panel controls the pump module and the heat exchanger and
is the interface to the transmitter control system. It uses very basic relay logic for
reliable operation. The cooling system control panel is connected to the External I/O
board in the Atlas Transmitter for monitoring and control. It also supplies AC power to
the pump module and the heat exchanger, and interfaces the fault and status information
from these units to the transmitter.
The cooling system control panel, shown in Figure 1-5 below, has local controls on the
front which allow manual selection of pump A or optional pump B and selection of
Remote/Local control. It also has the following status indicators: