PJ1000C/1300C/2000LCD
ELETTRONICA
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User Manual
Rev. 1.0 - 28/02/11
Without alarm condition, Bias voltage is regulated only in function of output
power set up, with a feedback mechanism based on the reading of the effectively
distributed power (AGC).
Bias voltage is also influenced from other factors like:
- Excess of reflected voltage
- External AGC signals (Ext. AGC FWD, Ext. AGC RFL,...)
- Excess of temperature
- Excess of absorbed current from a RF module.
7.3 PJ2000LCD Different Parts
7.3.1 Alimentatore
The
PJ2000LCD
power supply section is made up of a surge protection module
and two power supply units:
1.
Surge Protection module:
protects the equipment from possible voltage
surge events and electric discharges in the power mains.
2.
Power amplifier supply unit:
provides adequate power supply for RF power
amplifier modules. It is a switching power supply unit with PFC full range; for
details of the PFC and converter modules.
3.
Service power supply unit:
provides adequate power supply for all modules
except RF power modules. This is a power supply unit based on switching
technology.
7.3.1.1 PFC Unit
The PFC unit is a rectifier that modulates drawn current to ensure it is drawn
sinusoidally (as far as possible) and achieve a 99% power factor.
The PFC unit can operate on 230 VAC input voltage. It features a voltage selection
block that normally does not require setting.
7.3.2 Switching power supply
The switching power supply incorporated in this amplifier feeds 50 VDC to the RF
power modules with 64 A maximum current.
This module has a control input that enables output voltage reduction when needed
(for instance, in the event of RF output power reduction). Another input signal is
used to shut down the power supply (0V output voltage) when one of the following
conditions is verified:
