FG258A

High-current water-cooled ignitron for resistance-welder control. Its mercury-pool discharge switches enormous industrial welding currents.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 1
Base: -
Socket code: -
Base pins: -
Nominal heater: -

Description

The FG-258-A is a steel-jacketed water-cooled ignitron designed for high-current resistance-welder-control service and related industrial switching applications.

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: -
Nominal heater current: -
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

IgnitronPowerSwitch

X-ray radiationInterelectrode capacitances

No fixed ratings are recorded for this section.

Ignitron. Datasheet's primary maximum-rating table is welder-control service rather than rectifier service; applicable welder values are preserved as parameters rather than mis-promoted.

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

1968 General Electric Co

Published operating points and test conditions from this source.

SECTION 1

IgnitronPowerSwitch

Other

Welder Maximum Demand
2400 kVA
WelderControl 250to600Vrms
Welder Maximum Average Anode Current
355 A
WelderControl
Ignitor Allowed Positive Voltage
900 V
Ignition

Characteristic

Corresponding Average Anode Current at Maximum Demand
192 A
WelderControl
Ignitor Required Positive Voltage
200 V
Ignition