Data set 01
1960 Mazda
Published operating points and test conditions from this source.
SECTION 1
Triode
Construction
Filling
Gas
Characteristic
Control ratio
200:1
Other
Ambient temperature range
-55 to +75 C
Specialized - Thyratron ·Triode
21B12
Directly heated inert-gas thyratron for welding and motor-control service. Controlled gas discharge switches substantial industrial currents.
Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
- Sections
- 1
- Base
- -
- Socket code
- -
- Base pins
- -
- Nominal heater
- 2.5 V / 9 A
Description
Directly heated inert-gas-filled thyratron for welding or motor control.
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
- 2.5 V
- Nominal heater current
- 9 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
- Max cathode current
- 2.5 A
- Rectifier peak inverse voltage
- 1250 V
- Rectifier forward voltage drop
- 12 V
REDO promoted-field audit
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 02
1961 AEI Industrial Valves
Published operating points and test conditions from this source.
SECTION 1
Triode
Characteristics
Maximum peak forward anode voltage
10 kV
Maximum peak inverse anode voltage
1.25 kV
Maximum peak cathode current
30 A
Maximum surge cathode current
300 A
Voltage drop
12 V
Ionisation time
10 us
Deionisation time
1000 us
Anode-grid capacitance
3.8 pF
Grid-filament capacitance
2.5 pF
Data set 03
1961 Associated Electrical Industries
Published operating points and test conditions from this source.
SECTION 1
Triode
Characteristics
Maximum peak forward anode voltage
10 kV
Maximum peak inverse anode voltage
1.25 kV
Maximum peak cathode current
30 A
Maximum surge cathode current
300 A