User's Manual

V-1
Section V – Power Supply
Switching AC-DC power supplies are used to power the amplifier pallets, the control circuits, and all
of the fans. There are (2) power supplies paralleled in the power supply enclosure to generate the
necessary current for the amplifier pallets. These (2) supplies are paralleled at 31.0 Vdc nominally
and fed to the power amplifier enclosure via 4-AWG multi-stranded conductors and high current
connectors. There are no power supplies internal to the power amplifier enclosure, with the
exception of those found on the Series IIG control PCB. All fans run off this same supply, though
they pass through a series dropping resistor to lower the supply voltage, as the fans are 24Vdc.
A 24Vdc nominal power supply is located in the combiner enclosure. It simply supplies power to the
control PCB and the cooling fan.
The power supplies in the power supply enclosure are Mean Well PSP-1500. The power supply
found in the filter enclosure is a Mean Well S60-24. The switching power supplies are fully protected
against short circuit and output overload. Short circuit protection is a cycling type power limit. The
internal AC fuse is designed to blow only on a catastrophic failure in the unit – the fuse does not
blow on overload or short circuit. The thermal shutdown automatically recovers when the power
supply chassis cools down.
AC (220Vac) is fed into the power supply enclosure via a terminal block and then through a
resettable circuit breaker. The AC for the combiner enclosure (110Vac) is fed through a filtered EMI
AC entry. The current in the power supply is then current limited with a resettable circuit breaker
before passing through a rocker switch. This switch turns the AC on and off to the switching power
supply.