Power Supply Redundancy Operation / Power Reduction - Hitachi E-Compact High Power Series Operation Manual

In the EC701HP-BB3, EC702HP-BB3 and EC703HP-BB3, which uses one, two and three Power
Amplifiers, if one PS is removed the output power of the PA is reduced to 40% of the nominal power
of the PA. From the EC704HP-BB3 up to EC712HP-BB3, which uses four or more amplifier, if one
PS is removed the PA is shut off and the transmitter output power results follows the equations below.

3.2.9. Power Supply Redundancy Operation / Power Reduction

See below the description of the power supply redundancy operation of the transmitters EC701HP-BB3 to
the EC712HP-BB3:
EC701HP-BB3
The EC701HP-BB3 is composed by one Power Amplifier with the combination of eight pallets with the
Doherty technology.
Only in this model there is the possibility to operate with one of the two power supplies and with one or
more RF transistors damaged.
The Output power reduction by PSU fail follows the table below:
PS1
OK
FAIL
OK
The Output Power Reduction by RF transistor fail follows the equation below:
Where:
Pout = Output Power Results
Tok = Number of transistors working properly
Tt = Total number of transistors = 8
Pn = Nominal Output Power after the filter.
k = Reduction factor by dummy loads = 0.75
Output Power reduction by PSU fail
PS2
OK
OK
FAIL
=
E-Compact HP-BB3 Series
Output Power
100%
40%
40%
90 | 169