AR 10044005, Руководство по эксплуатации и обслуживанию

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Model 5000A225A
Rev B 43
If the LED is off, then either there is no power to the MPA or the internal Switch Breakout Board (SSB)
assembly failed to initialize.
If the LED is blinking, it means that locally the MPA is powered and the SBB is initialized.
If the LED is on solid, the communications link has been established with the DCP.
For the amplifier to be able to go to an RF on state, all MPA link LED’s must be on solid.
3.4.2 Power On/Operate Circuits
This section describes the functioning of the switches, relays and controls in the AC/DC power distribution
system. See Interconnect Diagram, 5000A225A, Schematic 10044006 for low voltage (200-240 VAC) or
10044007 for high voltage (380-415 VAC) and Interconnect, Driver Amp 10044184.
There are seven AC circuit breakers: the main circuit breaker and branch circuit breakers on the rear of the
amplifier, and one on the front panel of each MPA. The main circuit breaker disconnects all circuits from the
AC mains. The following description assumes that the main breaker is closed, making AC power available to
the amplifier components. In the DCU, +5VDC and +15VDC from PS1 are connected to the digital control
panel and the ALC board whenever CB main on the DCU rear panel is closed.
Relay K1, in the DCU, controls AC power to the main power supply in the MPA for amplifier operation. K1
controls the AC contactor in the MPA, which applies AC power to MPA PS2, the main power supply to the
MPA modules. Control for relay K1 loops through the interlock connector P9/J1 to the control panel. The
relay has +15V applied to their coils, and a “low” signal from the control panel to the other side of the coils
sinks current, activating the relays.
Note that in order to complete the circuit through K1, the external AC interlock circuit must be closed. The
I/O panel Safety Interlock connector provides pins 10 and 14 for this purpose. Another interlock circuit,
provided in the same connector, is used for RF inhibit, pins 1 and 8, if the user so desires. Both types can be
used simultaneously in their respective circuits. If the AC interlock circuit is open, a direct logic signal will be
applied to the Control Panel to display
AC Interlock on the display when Power On is attempted. If the
Inhibit interlock is open, Interlock will be displayed.
The energized relay K1 will energize the MPA contactor, applying the AC mains to the MPA main power
supply. The unit will then be in the STANDBY (RF Off) condition. In this state, all RF Power stages in the
DCU and the MPA are without DC power, making it impossible to produce any RF power. Power supply and
main cooling fans will be heard even though no DC is output from the main power supply. The DC output
power from the main power supply (PS2 in the MPA) when AC is supplied, is toggled on and off by the
RF
ON and RF OFF function.
Note that upon selecting RF ON there is a delay of a few seconds for the Test Rack/MPA to produce output.
This time is required for stabilization and confirmation of proper bias current levels to each transistor in the
system.
If the Keylock Switch is in the REMOTE position, the Power and Operate functions are the same except that
they can only be performed remotely (i.e., from the user’s computer), since the front panel controls are locked
out when the amplifier is in the Remote mode.