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

3CW20000A1

Water-cooled ceramic-metal industrial power triode for high-power RF generation, amplification, or modulation. Its manufacturer ratings emphasize continuous transmitting duty with high plate dissipation and substantial power handling.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
7.5 V / 100 A

Description

The EIMAC 3CW20000A1 is a water-cooled low-mu power triode for audio/modulator and voltage-regulator 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
7.5 V
Nominal heater current
100 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
Amplification factor
6.2
Max plate voltage
7000 V
Max plate dissipation
20000 W
Max grid dissipation
100 W
Max cathode current
5 A

Single triode section; promoted values mapped from printed General Characteristics and Maximum Ratings headings.

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 Eimac

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • The EIMAC 3CW20,000A1 is a ceramic/metal power triode intended

    3 a

    | The EIMAC 3CW20,000A1 is a ceramic/metal power triode intended

  • Voltage

    7.5 V

    GeneralCharacteristics | Voltage . ..... ... ... 7.5£037 V

  • Current, at 7.5volts

    7.5 A

    GeneralCharacteristics | Current, at 7.5volts . ... ................ 100 A

  • Amplification Factor (average)

    6.2

    GeneralCharacteristics | Amplification Factor (average) . .............. 6.2

  • O 51.0 pF

    51 pF

    GeneralCharacteristics | O 51.0 pF

  • it i e e e 4.1 pF

    4.1 pF

    GeneralCharacteristics | it i e e e 4.1 pF

  • O 28.5 pF

    28.5 pF

    GeneralCharacteristics | O 28.5 pF

  • 2. Capacitance values are for a cold tube as measured in a special shielded fixture in accordance with Electronic In

    2 a

    GeneralCharacteristics | 2. Capacitance values are for a cold tube as measured in a special shielded fixture in accordance with Electronic In-

Other

  • Envelope & Ceramic/Metal Seals

    250 °C

    | Envelope & Ceramic/Metal Seals . . ... ... ... ... .. . ..., 250°C

  • (Effective 9-1-74) © 1963, 1967, 1964 by Varian Printed in U.S.A

    9 A

    | (Effective 9-1-74) © 1963, 1967, 1964 by Varian Printed in U.S.A.

  • DC PLATE VOLTAGE

    7000 VOLTS

    MaximumRatings | DC PLATE VOLTAGE . ......... 7000 VOLTS Zero-Sig Plate Current . . .. ... 1.5 1.5 Adc

  • DC PLATE CURRENT

    5 AMPERES

    MaximumRatings | DC PLATE CURRENT .......... 5.0 AMPERES Max-Sig Plate Current ., .. ... 5.8 7.0 Adc

  • PLATE DISSIPATION

    20000 WATTS

    MaximumRatings | PLATE DISSIPATION .......... 20,000 WATTS Load Res. Plate-to-Plate . . . . .. 2460 1720 Q

  • GRID DISSIPATION

    100 WATTS

    MaximumRatings | GRID DISSIPATION .. ........ 100 WATTS Peak af Drive Voltage 2

  • (pertube)

    1300 v

    MaximumRatings | (pertube) . ............. 1300 1300 v

  • 2. Approximate value. Max-Sig Plate Qutput Power. . . . 24.4 29.1 kW

    2 kW

    MaximumRatings | 2. Approximate value. Max-Sig Plate Qutput Power. . . . 24.4 29.1 kW

  • 20,000 ohms

    20000 ohms

    MaximumRatings | 20,000 ohms.

  • Peak af Driving Voltage2

    290 v

    MaximumRatings | Peak af Driving Voltage2.......... 290 v

  • DC PLATE VOLTAGE

    7000 VOLTS

    MaximumRatings | DC PLATE VOLTAGE ......... 7000 VOLTS load Resistance . . ... ........... 212 Q

  • DC PLATE CURRENT

    1800 A

    MaximumRatings | DC PLATE CURRENT ......... See Class A derat- Max. Sig. Plate Output Power2 . . ... .. 1800 W

  • PLATE DISSIPATION

    20000 WATTS

    MaximumRatings | PLATE DISSIPATION ......... 20,000 WATTS 1. Adjust for specified dc plate current.

  • GRID DISSIPATION

    100 WATTS

    MaximumRatings | GRID DISSIPATION . ........ 100 WATTS 2. Approximate value.

  • DC PLATEVOLTAGE

    10000 VOLTS

    MaximumRatings | DC PLATEVOLTAGE ........... 10,000 VOLTS

  • PLATE DISSIPATION

    12000 WATTS

    MaximumRatings | PLATE DISSIPATION . .......... 12,000 WATTS

  • GRID DISSIPATION

    100 WATTS

    MaximumRatings | GRID DISSIPATION . .......... 100 WATTS

  • Filament: Current at 7.5volts

    7.5 A

    NOTE: TYPICAL OPERATION data are obtained by measurement or calculation from published characteristic curves. | Filament: Current at 7.5volts .. ......... ................. 94.0 104.0 A

  • Amplification Factor

    4.8

    NOTE: TYPICAL OPERATION data are obtained by measurement or calculation from published characteristic curves. | Amplification Factor ............ e e e 4.8 6.8

  • N 25.0 32.0 pF

    25 pF

    NOTE: TYPICAL OPERATION data are obtained by measurement or calculation from published characteristic curves. | N 25.0 32.0 pF

  • 1. Capacitance values are for a cold tube as measured in a special shielded fixture in accordance with Electronic In

    1 a

    NOTE: TYPICAL OPERATION data are obtained by measurement or calculation from published characteristic curves. | 1. Capacitance values are for a cold tube as measured in a special shielded fixture in accordance with Electronic In-

  • SK-1300 socket is available and recommended for normally be maintained for a short period of time

    1300 a

    | SK-1300 socket is available and recommended for normally be maintained for a short period of time

  • water of 10°C. Inlet water temperature should

    10 °C

    | water of 10°C. Inlet water temperature should

  • never exceed 55°C and outlet water temperature

    55 °C

    | never exceed 55°C and outlet water temperature

  • should never exceed 70°C. Where a liquid cool- CLASS A DERATING TABLE

    70 °C

    | should never exceed 70°C. Where a liquid cool- CLASS A DERATING TABLE

  • (watts) (gpm) Approx. psi 5000 2000

    5000 watts

    | (watts) (gpm) Approx. psi 5000 2000

  • should be maintained above 50 KQ/cm3, and life of the tube by a substantial percentage. It is

    50 a

    | should be maintained above 50 KQ/cm3, and life of the tube by a substantial percentage. It is

  • preferably above 250 KQ/cm3. A relative water good practice to determine the nominal filament

    250 A

    | preferably above 250 KQ/cm3. A relative water good practice to determine the nominal filament

  • quired, with 30 to 50 cfm of air at 50°C maximum some point in filament voltage there will be a

    30 °C

    | quired, with 30 to 50 cfm of air at 50°C maximum some point in filament voltage there will be a

  • tissue is dependent on frequency. Under 30 MHz,

    30 MHz

    | tissue is dependent on frequency. Under 30 MHz,

  • quencies as low as the 13 and 27 MHz bands. plication Engineering Dept., Power Grid Tube

    13 MHz

    | quencies as low as the 13 and 27 MHz bands. plication Engineering Dept., Power Grid Tube

  • A [2094]4l56 |

    2094 A

    | A [2094]4l56 | - - | [10399[10556] - -

  • (A} 39vLI0A Q49

    39 A

    | (A} 39vLI0A Q49

  • PLATE VOLTAGE (kV) CURVE #2542

    2542 kV

    | PLATE VOLTAGE (kV) CURVE #2542

  • (A) 39VLI0A 31V1d

    39 A

    | (A) 39VLI0A 31V1d

  • (v} LN34HND 31V1d

    4 v

    | (v} LN34HND 31V1d

Data set 02

1975 Eimac Tube Manual

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Amplification factor

    6.2

  • Heater/filament voltage

    7.5 V

  • Heater/filament current

    100 A

Other

  • Maximum plate voltage

    10000 V

  • Maximum plate dissipation

    20000 W

  • Maximum grid dissipation

    100 W

  • Maximum cathode/plate current

    5 A

  • Frequency for maximum ratings

    110 MHz

  • Audio-service maximum plate voltage

    7000 V

    Audio

  • Voltage-regulator maximum plate voltage

    10000 V

    VoltageRegulator

  • Voltage-regulator plate dissipation

    12000 W

    VoltageRegulator

Capacitance

  • Input/grid-filament capacitance

    51 to 51 pF

  • Output/plate-filament capacitance

    4.1 to 4.1 pF

  • Feedback/grid-plate capacitance

    28.5 to 28.5 pF

Construction

  • Cooling

    Water and forced air

Data set 03

1976 Eimac Tube Manual

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Amplification factor

    6.2

  • Heater/filament voltage

    7.5 V

  • Heater/filament current

    100 A

Other

  • Maximum plate voltage

    10000 V

  • Maximum plate dissipation

    20000 W

  • Maximum grid dissipation

    100 W

  • Maximum cathode/plate current

    5 A

  • Frequency for maximum ratings

    110 MHz

  • Audio-service maximum plate voltage

    7000 V

    Audio

  • Voltage-regulator maximum plate voltage

    10000 V

    VoltageRegulator

  • Voltage-regulator plate dissipation

    12000 W

    VoltageRegulator

Capacitance

  • Input/grid-filament capacitance

    51 to 51 pF

  • Output/plate-filament capacitance

    4.1 to 4.1 pF

  • Feedback/grid-plate capacitance

    28.5 to 28.5 pF

Construction

  • Cooling

    Water and forced air