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4. Power Amplifier
4.1 Output device protection by means of active device current limitation, active voltage
limitation, output power limitation, active reflected power limitation, over-temperature
limitation, and passive device snubber circuits. These features enable the generator to
encounter any load condition without failure.
4.2 5000 Watts output power is attained through the summed output currents of four 1250 Watt
RF power amplifiers. Each power amplifier is comprised of eight FETs capable of 340 Watts
dissipation each, arranged in a push pull configuration with four FETs per side in parallel.
Each device runs at about 50 watts dissipation under normal operating conditions. Each
device can withstand 300 volts from drain to source with the active voltage limit circuitry set
for 175 volts MAX. Each power amplifier is current - limited to 40 Amps.
4.3 Each 1250 Watt power amplifier is built upon a solid copper heatsink block that is naturally
corrosion resistant. Four 4” fans reduce any possibility of condensation developing internally
in the unit.
4.4 Two different manufacturer’s FET devices to be qualified in specified unit.
5. Input Power Requirements
5.1 Electrical input requirements:
208 VAC, 3 phase
50/60 Hz
20 A
5.2 Manufacturers input specification:
5.2.1 Nominal Input: 208VAC, 3 phase, 50/60 Hz, 4 wire (3 wire with protective
earth ground).
5.2.2 Voltage AC Input Range 195-225VAC
5.2.3 Input Fusing: 25 Amps Max.
5.2.4 Power Consumption: Approx. 7.5KVA
5.2.5 Power Consumption by RF Generator at rated output: Less than 1.5KW to be
dissipated via water cooling. Less than 500 watts to be dissipated by internal fan
air cooling.
5.2.6 Grounding: AC grounded via AC Line Connector. PE/Safety 1/4” ground stud
provided at back panel.
6. Front Panel Controls & Indicators
6.1 AC On Indicator: Green LED indicates AC power on.
6.2 RF On Indicator: Green LED indicates RF power is enabled.
6.3 Remote/Local Indicators: Yellow LED indicates control status.
