Hammond 161EA20 1.2VA 20V Center-Tapped PCB Power Transformer

The 161EA20 is a 1.2 VA low voltage power transformer for printed circuit board mounting, built with a single 115V primary rated for 60 Hz only. Its secondary delivers 20V centre-tapped at 60mA when the windings are used in series, or 10V at 120mA when they are connected in parallel. It suits OEM engineers and designers who need a board-level 20V C.T. or 10V AC source from a 115V line.

According to the part drawing, the primary connects across pins 1 and 2 and the two secondary windings sit on pins 3-4 and 5-6, each marked 10V / 60mA per secondary winding. The drawing lists a no-load secondary voltage of 11.67V ±2% per winding and an excitation current of 19.2mA max. @ 115V, 60Hz, pin 1 - pin 2. A red dot above pin 2 marks the mechanical winding start for manufacturing only and is not a polarity dot.

Construction follows the 160-161 Series design: a vertical mount, split bobbin transformer; the 1.2 VA size is non-concentric wound. Low primary-to-secondary coupling means no electrostatic shield is required. Insulation is Class B (130 degrees C) with a Hipot rating of 2,000V RMS, and the 161EA20 drawing specifies a primary-to-secondary hipot test of 1500V, 60Hz, 1 sec.

Drawing dimensions for the 161EA20 are A 1.451" ±0.031, B 1.130" ±0.031 and C 1.245" ±0.063, with pin size 0.018" x 0.041" ±0.005, E 1.000" ±0.031 and G 0.312" ±0.031 (2 places). The shipping weight is 0.19 lbs (0.09 kg).

The 161EA20 is CSA certified (File # LR3902) and UL recognized (File #E207860), and it is listed as RoHS and REACH compliant. If the design must also run from 230V or 50 Hz supplies, the dual primary 115/230V counterpart in the ordering table is 160E20.