Hammond 166V5 5V CT 20A Open Style Power Transformer, 100 VA

The 166V5 is a 100 VA open style power transformer whose 5 V centre-tapped secondary is rated for 20 A, fed from a single 115 V, 60 Hz primary. Its 20 A rating is the highest among the 5 V C.T. parts in the 166 Series table, and it suits heavy low-voltage loads such as filament banks or high-current rectified supplies.

Construction follows the 166 Series design: an open style unit on a channel bracket, a dual bobbin winding arrangement that needs no electrostatic shield, and Class B insulation rated to 130 °C for extra protection, while the transformer is UL listed as a Class A (105 °C) design. Every unit is hi-pot tested at 2,000V RMS, and it is supplied with minimum 6 in long leads. At 20 A it doubles the secondary current of the 166S5 while keeping the same 5 V C.T. output.

Overall dimensions are A 4.50 in (114 mm), B 2.50 in (64 mm) and C 3.00 in (76 mm). The 166V5 mounts with two holes of 0.203 in (5.2 mm) spaced 4.00 in (102 mm) hole to hole (mounting reference C). Shipping weight is 3.5 lbs (1.59 kg). On the drawing schematic the primary leads are black (BLK/BLK) and the secondary leads are green (GRN/GRN) with a green/yellow (GRN/YEL) centre tap.

The transformer is UL listed and CSA certified, and it is declared RoHS and REACH compliant. Check the 115 V, 60 Hz primary against your supply before ordering; for 117/234 V or 50/60 Hz operation across the range, or dual secondaries, the manufacturer points to its 266 Series.