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Power - Triode (over 1000V 100W) ·Triode

3R222S

Water-cooled industrial triode for high-power Class C RF-heating oscillator service. Rated for 10 kW plate dissipation, with published operating conditions delivering approximately 25–26 kW RF output.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
8 V / 125 A

Description

The 3R222S is a water-cooled industrial triode for high-power class-C industrial RF heating oscillator service.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
Base pins
-
Nominal heater voltage
8 V
Nominal heater current
125 A
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

Terminal pinout

Electrical assignments shared by every tube using this base designation.

No verified pinout is recorded for this base designation.

Section ratings

1 physical section, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances
Transconductance
0.06 S
Amplification factor
12
Max plate voltage
7000 V
Max plate dissipation
10000 W
Max grid dissipation
500 W

Published maximum ratings and characteristics audited; remaining values retained densely in parameter table.

Source-dependent data

Operating conditions by source

Each block preserves the test conditions and published values from one reference. Values from different sources are intentionally kept separate.

Data set 01

1962 ITT

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Anode voltage (peak value of direct voltage plus ripple)

    70 kV

    Anode voltage (peak value of direct voltage plus ripple) 7,0 kV

  • Direct anode current

    60 A

    Direct anode current : 6,0 A

  • Anode dissipation, continuous

    10 kW

    Anode dissipation, continuous 10 kW

  • Grid dissipation, continuous

    500 W

    Grid dissipation, continuous 500 W

  • Grid current (Note [1]

    1 A

    Grid current (Note 1) ' 1,4 A

  • Grid current (Note [2]

    14 A

    Grid current (Note 1) ' 1,4 A

  • Direct negative grid voltage [1]

    -1 V

    Direct negative grid voltage -1 500 v

  • Direct negative grid voltage [2]

    500 V

    Direct negative grid voltage -1 500 v

  • Maximum frequency for above ratings

    30 MHz

    Maximum frequency for above ratings 30 MHz

  • Note

    1

    Note 1, This figure is given for guidance. Grid dissipstion is absolute

  • Filament voltage [1]

    80 V

    Filament voltage 8,0V* 5%

  • Filament voltage [2]

    5 V

    Filament voltage 8,0V* 5%

  • Filament current, nominal

    125 A

    Filament current, nominal 125 A

  • Direct anode voltage '

    60 kV

    Direct anode voltage ' 6,0 kV

  • Direct grid voltage

    -660 V

    Direct grid voltage -660 , Vv

  • Direct anode current

    56 A

    Direct anode current 5,6 A

  • Peak r.f. grid voltage

    930 V

    Peak r.f. grid voltage - 930 v

  • Direct grid current (Note [1]

    2 mA

    Direct grid current (Note 2) 750 (1 200) mA

  • Direct grid current (Note [2]

    750 mA

    Direct grid current (Note 2) 750 (1 200) mA

  • Direct grid current (Note [3]

    1 mA

    Direct grid current (Note 2) 750 (1 200) mA

  • Direct grid current (Note [4]

    200 mA

    Direct grid current (Note 2) 750 (1 200) mA

  • Grid dissipation (Note [1]

    2 W

    Grid dissipation (Note 2) 260 W

  • Grid dissipation (Note [2]

    260 W

    Grid dissipation (Note 2) 260 W

  • Grid resistor

    900

    Grid resistor 900 . [y

  • Power output

    26 kW

    Power output 26 kW

  • Power output, less drive.-...= e

    25 kW

    Power output, less drive.-...= e 25 kW

  • Power into load at [1]

    85 kW

    Power into load at 85% transfer eff1c1ency - 21 kW

  • Power into load at [2]

    21 kW

    Power into load at 85% transfer eff1c1ency - 21 kW

  • Cold filament resistance

    45 ohm

    Cold filament resistance 0,0045 Q

  • It is recommended that some resistance or reactance be introduced

    4 ohm

    It is recommended that some resistance or reactance be introduced 4into the

  • Mutual conductance (at Vg = [1]

    2 mA/V

    Mutual conductance (at Vg = 2kV : Vg = =B7V) ) : 60 mA/V

  • Mutual conductance (at Vg = [2]

    60 mA/V

    Mutual conductance (at Vg = 2kV : Vg = =B7V) ) : 60 mA/V

  • Grid to anode

    56

    Grid to anode 56 pF

  • Grid to filament

    100

    Grid to filament 100 pF

  • Anode to filament ‘

    30

    Anode to filament ‘ 3,0 pf

  • The anode must be cooled by an adequate water flow (see Figures [1]

    3

    The anode must be cooled by an adequate water flow (see Figures 3 and 4). It

  • The anode must be cooled by an adequate water flow (see Figures [2]

    4

    The anode must be cooled by an adequate water flow (see Figures 3 and 4). It

  • CN

    1

    CN-1A Filament connector, small

  • CN~

    1

    CN~1B Filament connector, large

  • CN

    1

    CN-1C Grid connector

  • Fig

    1 V

    Fig. 1. Constant Voltage Characteristic

  • Fig

    2 A

    Fig. 2. Constant Current Characteristic

  • Water Temperature of

    60

    Water Temperature of 60°C