Hammond 187F20 20V CT 100VA Chassis Mount Power Transformer

The 187F20 is a 115 VAC single-primary power transformer from the 187 Series, rated 100 VA with a 20V C.T. secondary at 5 A. It is an open style, channel frame design built to mount directly to a chassis, suited to OEM engineers and equipment builders who need a compact low-voltage supply transformer that runs on 50/60 Hz mains.

The 187F20 pairs a 20 V centre-tapped secondary with a 5 A rating. Its part drawing adds test data: no-load secondary voltage of 22.33 V (±2%) across the full winding and 11.17 V (±2%) on each half, excitation current of 126 mA max at 115 V, 60 Hz, and a 2500 V, 60 Hz, 1-second primary-to-secondary hipot.

Construction uses a split bobbin, which eliminates the need for an electrostatic shield, and Class B (130 C) insulation. Temperature rise is designed not to exceed Class A for longer life. Combination solder or quick connect terminals let you choose between soldered leads and push-on connectors, and every unit in the series is hi-pot tested to 2 KV RMS.

Dimensions follow the F frame size of the series table: length 4.03 in (102 mm), depth 2.25 in (57 mm) not including terminals or 2.62 in (67 mm) to the terminals, height 2.56 in (65 mm), and 3.50 in (89 mm) mounting centres. Shipping weight is 2.7 lbs (1.22 kg). If your design needs a 115/230 VAC dual primary with the same secondary, the series table lists 186F20 as the equivalent 186 Series part.

The series is UL listed (# E207860) Type 3AH and CSA Certified, and the 187F20 is RoHS and REACH compliant.