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Rectifier - Half Wave ·Rectifier

NL635

Directly heated mercury- and gas-filled industrial rectifier for supplies up to approximately 250 V DC. Rated for about 1 kV peak inverse voltage and 6.4 A output.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
FOR
Socket code
SJ4
Base pins
-
Nominal heater
2.5 V / 18 A

Description

NATIONAL POWER TUBE NL-635 is a sturdy rectifier tube designed especially for industrial power rectifier applications up to 250 volts dc. It is mercury and gas filled for efficiency, long life, and the ability to withstand high inverse voltages. NL-635 utilizes a No. 412 industrial 4-pin base. It is avail- able with a bracket base for panel mounting under the type number NL-635P and the new National lug type base under the number NL-635L. NATIONAL ELECTRONICS, INC. GENEVA, ILLINOIS,

Socket description

Super-jumbo 4-contact bayonet

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
FOR
Socket code
SJ4
Base pins
-
Nominal heater voltage
2.5 V
Nominal heater current
18 A
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

FOR - 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

Rectifier

X-ray radiationInterelectrode capacitances
Max cathode current
6.4 A
Rectifier peak inverse voltage
1000 V
Rectifier nominal output current
6.4 A
Rectifier peak forward current
77 A
Rectifier forward voltage drop
9 V
Rectifier warm-up time
60 s

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

Rectifier

Other

  • rectifier applications up to

    250 volts dc. It is mercury and gas filled for efficiency, long life, and the

    Source technical-information table; wording preserved from datasheet.

  • ability to withstand high inverse voltages. NL-635 utilizes a No

    412 industrial 4-pin base. It is avail- V

    Source technical-information table; wording preserved from datasheet.

  • do Amperes output (maximum)

    6,4 A

    Source technical-information table; wording preserved from datasheet.

  • Instantaneous Amperes output (maximum)

    77 A

    Source technical-information table; wording preserved from datasheet.

  • Maximum time of averaging anode current (seconds)

    20 A

    Source technical-information table; wording preserved from datasheet.

  • Maxinnlm peak inverse volts

    1000 V

    Source technical-information table; wording preserved from datasheet.

  • Filament volts

    2.5 V

    Source technical-information table; wording preserved from datasheet.

  • Filament amperes

    18 ± 2 A

    Source technical-information table; wording preserved from datasheet.

  • Filament heating time (seconds)

    60 s

    Source technical-information table; wording preserved from datasheet.

  • Maxim u m ac short circuit current (amperes)

    7'70 A

    Source technical-information table; wording preserved from datasheet.

  • Condensed mercury temperature limits (°C)>.,

    — 40 to +100 C

    Source technical-information table; wording preserved from datasheet.

  • Approximate temperature rise, cond. mercury above ambient (°C)

    30 C

    Source technical-information table; wording preserved from datasheet.

  • Net weight (ounces)

    6 oz

    Source technical-information table; wording preserved from datasheet.

  • Approx. shipping weight (lbs.)

    4 lb

    Source technical-information table; wording preserved from datasheet.

  • Satisfactory operation will be obtained between —40 to

    +100°C. For long life the tube should be operated between ±40

    Source technical-information table; wording preserved from datasheet.

  • to ±100°C condensed mercury, or approximately

    +10 to ±70°C ambient.

    Source technical-information table; wording preserved from datasheet.

  • NL-635

    NL- 635P | NL-635L

    Source technical-information table; wording preserved from datasheet.

  • ANODE

    ANODE | .568' DIA. CAP

    Source technical-information table; wording preserved from datasheet.

  • 566 DIA

    .566' DIA. | CI —5

    Source technical-information table; wording preserved from datasheet.

  • CI-5

    CI -5

    Source technical-information table; wording preserved from datasheet.

  • INDUSTRAIL

    I8

    Source technical-information table; wording preserved from datasheet.

  • A4-81

    16

    Source technical-information table; wording preserved from datasheet.

  • 5z'I}_ 2I

    SLOTS -5 2 WIDE s

    Source technical-information table; wording preserved from datasheet.

  • FILAMENT

    / | O | O | FILAMENT 6 | FILAMENT | CAT100DE

    Source technical-information table; wording preserved from datasheet.

  • FILAMENT

    9 R. CIRCL

    Source technical-information table; wording preserved from datasheet.

  • CATHODE

    9

    Source technical-information table; wording preserved from datasheet.

Characteristic

  • Typical arc drop at

    20 amperes peak (volts) g

    Source technical-information table; wording preserved from datasheet.

  • Typical Anode starting voftage (volts)

    20 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

Rectifier

Other

  • Maximum DC output current

    6.4 A

  • Maximum instantaneous output current

    77 A

  • Maximum peak inverse voltage

    1000 V

Characteristic

  • Filament heating time

    60 s

  • Typical arc drop

    9 V

  • Typical anode starting voltage

    20 V

Construction

  • Filling

    Mercury vapor

Application

  • Service

    Industrial power rectifier