Schaffner RD Series Common Mode Chokes. The RD series of chokes from Schaffner are attenuating common-mode or asymmetric (P/N ->E) interference signals, by being connected in series with the phase and neutral lines of an AC powerline input. The Symmetrical of the noise are also attenuated due to the leakage inductance of the windings. 6A to 64A current ratings Dual, Triple and Quad choke configurations. Applications. Filter networks Decoupling tasks Low power switch mode regulators