Magnetek Triad F-357X Filament Power Transformer 115-230V 25.2VCT 1A 50/60Hz

Magnetek Triad F-357X Filament Power Transformer 115-230V 25.2VCT 1A 50/60Hz

The Magnetek Triad F-357X is a chassis-mount filament power transformer with a dual primary winding that accepts either 115V or 230V AC input at 50/60 Hz and delivers a 25.2V center-tapped secondary at 1.0 amp. The dual-primary design lets you wire the transformer for your local mains voltage — 115V or 230V — using the color-coded leads per the wiring diagram printed on the label. Multiple color-coded leads are provided for both primary configurations and the center-tapped secondary output.

Specifications & What's Included

• Model: F-357X (also marked F-357 X)
• Type: Filament Power Transformer (chassis mount)
• Primary Voltage: 115V AC or 230V AC (dual primary, selectable via wiring)
• Primary Frequency: 50/60 Hz
• Secondary Voltage: 25.2V CT (center tap)
• Secondary Current: 1.0A
• Secondary Leads: GRN-GRN / YEL-GRN (center tap configuration)
• Primary Wiring – 115V: BLK & YEL/BLK leads; tie BLK to RED/BLK and YEL/BLK to BLK/GRN
• Primary Wiring – 230V: BLK & BLK/GRN leads; tie YEL/BLK to RED/BLK
• Core construction: laminated EI core with color-coded flying leads
• Manufacturer: Magnetek Triad
• Includes: transformer unit and original MagneTek box (box may be open)

Applications

Filament transformers like the F-357X are general-purpose chassis-mount power transformers used to step mains AC voltage down to a lower AC voltage for powering electronic circuits, tube filaments, relays, control panels, and low-voltage power supply stages. The 25.2V center-tapped secondary is a common output used with full-wave rectifier bridges to produce regulated DC supply rails — the center tap serves as the DC ground reference in a full-wave rectifier circuit, making this configuration widely used in linear power supplies. The dual-primary design is practical for equipment intended to operate on either North American (115V/60Hz) or European (230V/50Hz) mains, requiring only a rewire of the primary leads rather than a separate transformer. Magnetek's Triad line has long been a staple in industrial control, instrumentation, and electronics manufacturing, and this style of open chassis transformer remains in active use for OEM equipment builds, repair and replacement, and custom power supply designs.