Hammond 742A 1250 VA 5,000V C.T. Plate Transformer, 117/234V Primary

The 742A is a 700 Series high voltage (plate) transformer rated 1250 VA, with a dual 117/234 VAC, 50/60 Hz primary and a 5,000V C.T. R.M.S. high voltage secondary. It suits builders and service technicians who need a centre-tapped plate winding for a rectified high voltage supply and want the flexibility of either a 117 VAC or 234 VAC mains connection.

The high voltage secondary is rated 250ma under CCS (Continuous Commercial Service) and 375ma under ICAS (Intermittent Commercial or Amateur Service); the 1250 VA figure is a CCS rating. The unit can be run in either a full wave bridge or a full wave C.T. rectifier circuit, and the series design guide gives the voltage and current factors for each rectifier and filter arrangement.

Construction is enclosed with a 4 hole chassis mount and minimum 6" long leads. Insulation is Class A (105 degrees C), each design is Hi-Pot tested at a minimum of twice the secondary voltage, and the series is CSA certified (209651). Because the 5,000V C.T. secondary is at 2,000 VAC or above, its leads are brought out through rubber bushings. The part is listed as RoHS and REACH compliant.

Primary wiring for the 742A: for 117 VAC input, connect Blue to Black and Brown to White; for 234 VAC input, connect Brown to Black and the input is Blue and White. The 742A is offered only with the 117/234 VAC primary; the 700 Series ordering table lists no 115 VAC version, and its 5,000V C.T. secondary is the highest voltage in the series. Shipping weight is 34.7 lbs (15.74 kg). The series table lists the unit weight as 26 lbs.