Hammond PWDF13255 Collins KW-1 T-501 872A Rectifier Filament Transformer

PWDF13255 is an exact replacement for the Collins KW-1 rectifier filament transformer, position T-501, which supplies the 872A filaments. It is a Peter Dahl design in Hammond's PWDAHL Series of magnetics for amateur radio products and is intended for KW-1 owners and restoration specialists.

The single secondary is rated 5.0 VCT @ 15A CCS with 10 KVDC insulation. The primary is 115 VAC, 60 Hz, single phase. Because it is listed for 60 Hz, buyers outside North America should follow the series note that 50 Hz use calls for a part marked 50/60 Hz.

Construction uses an EI-150 x 1.25" 29GRH core, listed as Style 5 on the series style sheet. Approximate weight is 6 lbs and the shipping weight is 6 lbs (2.72 kg). PWDF13255 is REACH compliant and RoHS compliant.

Hammond explains that PWDAHL transformers are usually built to order one at a time and that it is best to confirm availability by phone or e-mail. The part is catalogued under UPC 623980031835 and UNSPSC 39121301.

The 10 KVDC insulation rating is the key difference between this unit and a general-purpose 5 volt filament transformer, and it is why the ordering table positions it as an exact replacement for the KW-1 T-501.