Hammond 266L20 40VA Transformer, 20V C.T. or 10V Parallel Output

The 266L20 is a 40 VA dual-primary power transformer rated 20 V center tapped at 2 A, or 10 V at 4 A in parallel, for low-voltage supplies in chassis-mounted equipment. It belongs to the Hammond 266 Series of low voltage/filament transformers and is aimed at OEM engineers, repair technicians and panel builders who mount the transformer directly to a chassis.

The primary is a dual 117/234 VAC, 50/60 Hz winding: connect the two primary halves in parallel for 117 V or in series for 234 V. The dual secondaries can be used as a center-tapped secondary (20V @ 2A), connected in parallel (10V @ 4A) or used individually, and the unit is designed for use with all windings engaged.

Construction is open style with a dual bobbin design, so no electrostatic shield is required. Hammond uses Class B (130 °C) insulation for extra protection, while the design is UL listed as Class A (105 °C). Every unit is hi-pot tested at 2,000V RMS, and all leads are a minimum of 6 in long. The transformer is UL listed (# E207860) Type 3AH, CSA certified (209651), and RoHS and REACH compliant.

The 266L20 uses mounting style A with 0.19 in (5 mm) mounting holes. Its listed dimensions are A 4.00 in (102 mm), B 2.25 in (57 mm), C 2.62 in (67 mm) and D 3.56 in (90 mm). It weighs 2.63 lbs and ships at 2.5 lbs (1.13 kg).