Hammond 164E24 2.4VA 24V Center-Tapped PCB Transformer, 115V Primary

Designed for printed circuit boards, the 164E24 is a low-profile 2.4VA power transformer with an economical single 115V primary that operates on 50 or 60 Hz. Engineers specifying low-voltage AC for board-level circuits get a 24V centre-tapped secondary from a split bobbin design. In series the secondaries deliver 24V with centre tap at 0.1A, and in parallel 12V at 0.2A.

The secondary is made up of two windings that are wound non-concentrically on the split bobbin. That arrangement keeps primary-to-secondary coupling low, so no electrostatic shield is required. Insulation is Class B (130 degrees C) and the unit is hipot rated at 2,500V RMS. Note that the design requires all windings to be used, so connect both secondaries in series or in parallel.

The E-size body measures 1.38 in long by 1.13 in wide by 1.19 in high and weighs 0.25 lb per the series specification sheet. At 2.4VA it needs no mounting hardware: the unit is held by its P.C. board pins, which use industry-standard pin spacing.

The 164E24 drawing labels each secondary winding (pins 5-6 and pins 7-8) at 12V, 100mA, with the 115V primary on pins 1 and 4; pin numbers are embossed on the bobbin flange.

The transformer is c UL us recognized and listed as RoHS and REACH compliant. Where a design must run from 115V or 230V, the dual-primary equivalent in the same series is 162E24.