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Specialized - Thyratron ·Triode

NL730

Quick-heating gas-and-mercury thyratron for motor-speed control and regulated rectifiers. Its heavy cathode supports substantial industrial controlled current.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
DOWN
Socket code
-
Base pins
-
Nominal heater
2.5 V / 12 A

Description

NATIONAL POWER TUBE NL-730 is a quick heating thyratron especially designed for motor speed con- trol and regulated rectifier applications. It is gas and mercury filled to give quick starting, long life, and wide temperature limits. NL-734 THYRATRON TUBE TECHNICAL INFORMATION do Amperes output (maximum) 3.2 Maximum negative grid voltage before conduction (volts) 500 Instantaneous Amperes output (maximum) 40 Maximum negative grid voltage during conduction Maximum time of averaging anod

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
DOWN
Socket code
-
Base pins
-
Nominal heater voltage
2.5 V
Nominal heater current
12 A
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

DOWN - 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
Max plate voltage
1500 V
Max cathode current
3.2 A
Rectifier nominal output current
3.2 A
Rectifier peak forward current
40 A

Published ratings and characteristics promoted where canonical fields apply.

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

1956 National Electronics Industrial Tubes

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • 3.2 Amperes do —

    40 Amperes Peak A

    Source technical-information table; wording preserved from datasheet.

  • do Amperes output (maximum)

    3.2 | Maximum negative grid voltage before conduction A

    Source technical-information table; wording preserved from datasheet.

  • (volts)

    500 V

    Source technical-information table; wording preserved from datasheet.

  • Instantaneous Amperes output (maximum)

    40 A

    Source technical-information table; wording preserved from datasheet.

  • Maximum time of averaging anode current (seconds) _...15

    (volts) | 10 A

    Source technical-information table; wording preserved from datasheet.

  • Maximum peak inverse volts

    1500 | Maximum critical grid current (microamps) | 10 V

    Source technical-information table; wording preserved from datasheet.

  • Maximum peak forward volts

    1500 | Ionization time (approx., microseconds) | 10 V

    Source technical-information table; wording preserved from datasheet.

  • Condensed mercury temperature limits (°C)* —40 to

    80 C

    Source technical-information table; wording preserved from datasheet.

  • Filament volts

    2.5 V

    Source technical-information table; wording preserved from datasheet.

  • Maximum ac short circuit current (amperes)

    560 A

    Source technical-information table; wording preserved from datasheet.

  • Filament amperes

    12 ± | 1.5 A

    Source technical-information table; wording preserved from datasheet.

  • Approx. temp. rise, cond. mercury above ambient (°C)

    30

    Source technical-information table; wording preserved from datasheet.

  • Filament heating time (seconds)

    30 | Mounting position | Vertical, base down s

    Source technical-information table; wording preserved from datasheet.

  • Grid control characteristic

    See Curve | Approx. shipping weight (lbs.) | 4

    Source technical-information table; wording preserved from datasheet.

  • *The tube may be started and satisfactory operation will result between —40 and

    +80°C. For maximum life the condensed

    Source technical-information table; wording preserved from datasheet.

  • mercury temperature after warm-up should run between

    +40 and +80°C which corresponds to approximately +10 to +50°C C

    Source technical-information table; wording preserved from datasheet.

  • a00

    0

    Source technical-information table; wording preserved from datasheet.

  • 12 -e

    -4 14 iD

    Source technical-information table; wording preserved from datasheet.

  • DC

    SAID | VOLTA44 | AT -TART | OF DISONAM4-

    Source technical-information table; wording preserved from datasheet.

  • Printed

    In | USDA-10 | -II —G. I:,

    Source technical-information table; wording preserved from datasheet.

Characteristic

  • Deionization time (approx., microseconds)

    1000 us

    Source technical-information table; wording preserved from datasheet.

  • Anode to grid capacitance (uuf)

    4 pF

    Source technical-information table; wording preserved from datasheet.

  • Typical arc drop at 12 amperes peak (volts)

    12 | Net weight (ounces) | 7 V

    Source technical-information table; wording preserved from datasheet.

Data set 02

1957 National Electronics

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Maximum peak forward voltage

    1000 V

  • Maximum peak output current

    40 A

  • Maximum dc output current

    3.2 A