There is a long list of terminal combinations and voltages on the nameplate, as you might imagine is necessary with the 9 terminals of the T. In case the fine print of yours is illegible, here is what mine says:
C TO D 2 VOLTS
C TO E 4 VOLTS
C TO F 6 VOLTS
C TO G 8 VOLTS
C TO H 10 VOLTS
B TO C 8 VOLTS
B TO D 10 VOLTS
B TO E 12 VOLTS
B TO F 14 VOLTS
B TO G 16 VOLTS
B TO H 18 VOLTS
A TO B 7 VOLTS
A TO C 15 VOLTS
A TO D 17 VOLTS
A TO E 19 VOLTS
A TO F 21 VOLTS
A TO G 23 VOLTS
A TO H 25 VOLTS
VOLTAGES OBTAINED WHEN USING SWITCH
C TO U - 2-4-6-8-10 VOLTS
B TO U - 10-12-14-16-18 VOLTS
A TO U - 17-19-21-23-25 VOLTS