I'm having some trouble getting a good understanding of how the EM fields are working in a circuit. Essentially, Maxwell's equations and boundary conditions at a perfect conductor are confusing me. If, in a perfect conductor, the E and B fields are zero, then how does a voltage appear in a circuit? IE, if we attached an ideal DC voltage source to a loop of perfect conductor with a resistor in the middle, then if there is no E or B in the loop, is there a voltage at the resistor? Any references to understanding the fields when DC and AC are applied to a t-line or circuit would be very helpful.