APPENDIX
USEFUL FORMULAS
FOR IVAC CIRCUITS
USEFUL AC FORMULAS
PERIOD TIME (t)
L/R TIME CONSTANT (TC)
FREQUENCY (f)
MUTUAL INDUCTANCE (M)
AVERAGE VOLTAGE OR CURRENT
TOTAL INDUCTANCE (LT) Series without
magnetic coupling
EFFECTIVE VALUE OF VOLTAGE OR
CURRENT
TOTAL INDUCTANCE (LT) PARALLEL
(No magnetic coupling)
MAXIMUM VOLTAGE OR CURRENT
CAPACITANCE (C)
OHM’S LAW OF AC CIRCUIT
CONTAINING ONLY RESISTANCE
RC TIME CONSTANT (t)
AIV-1
TOTAL CAPACITANCE (CT) SERIES
APPARENT POWER
POWER FACTOR (PF)
TOTAL CAPACITANCE (CT) PARALLEL
VOLTAGE ACROSS THE SECONDARY
(Es)
INDUCTIVE REACTANCE (XL)
CAPACITIVE REACTANCE (XC)
VOLTAGE ACROSS THE PRIMARY (Ep)
IMPEDANCE (Z)
CURRENT ACROSS THE SECONDARY
(Is)
OHM’S LAW FOR REACTIVE CIRCUITS
CURRENT ACROSS THE PRIMARY (Ip)
OHM’S LAW FOR CIRCUITS
CONTAINING RESISTANCE AND
REACTANCE
TRANSFORMER EFFICIENCY
REACTIVE POWER
AIV-2