De gamle kondensatorer der står CM på er angivet ud fra den oprindelige måde at definere ladning (Se neden for).
En CM er ca. lig med 1,11 pF.
Sakset fra
http://mysite.du.edu/~jcalvert/phys/caps.htmIn an ideal capacitor, the voltage is proportional to the charge, and the constant of proportionality is the capacitance C. That is, Q = CV, or C = Q/V. Most capacitors are close to ideal if the voltage does not vary too rapidly, and is not excessive. Unit capacitance results when unit charge means unit voltage. In the practical system, unit charge is 1 coulomb, and unit voltage is 1 volt, or 1 joule/coulomb. The corresponding unit of capacitance is the farad, which is one coulomb per volt. This happens to be an absurdly large unit, so the microfarad, μF, is commonly used. In Gaussian or electrostatic units (esu), the unit of charge is the esu (or statcoulomb; c/10 = 3 x 109 esu = 1 C) and the unit of potential is the statvolt, which is about 300 volt. The unit of capacitance is then the centimetre, or one esu per statvolt. From these figures, it follows that 1 cm = 1.11 x 10-12 F = 1.11 pF.