SCOTT T TRANSFORMER, 500 KVA

Specifications:

Scott T Transformer, 500 KVA, 3 PH, 60 Hz, P/N 10288L1
Primary (1, 2, 3): 480 VAC L-L, 601 Amps
Secondary MAIN (4, 5, 6): 120/240 VAC, 1042 Amps
Secondary TEASER (7, 8, 9): 120/240 VAC, 1042 Amps
Copper windings
Core Loss: 1.4 kW, Copper Loss: 4.8 kW, Temperature Rise: 65 degrees C
NEMA 1 enclosure: 60” H x 60″ W x 36″ D,Total Weight: 4300 lbs.
Photo of the Scott T Transformer with primary (1, 2, 3) is shown below:

Photo of the indoor enclosure (60” W x 60” H, 36” D) is shown below:

The schematic diagram of the Scott T Transformer is shown below:

Preliminary Design Summary of the Scott T Transformer is shown below:

1. Electrical Specifications

2. Scott T Winding Schedule

Turns basis: 52 MAIN primary turns gives approximately 9.23 V/turn. The 45-turn TEASER primary closely matches the required 86.6%
Scott ratio. Each 26-turn secondary produces approximately 240 VAC with a 13-turn midpoint for 120 VAC.

Secondary terminals: MAIN: 4-5 = 120 V, 5-6 = 120 V, 4-6 = 240 V. TEASER: 7-8 = 120 V, 8-9 = 120 V, 7-9 = 240 V.

3. Core and Lamination Construction

The enlarged 7″ common return leg provides approximately 56 in2 gross cross section versus 40 in2 on each wound leg. This accommodates the vector combination of MAIN and TEASER flux in the shared return path.