There are four markings on the standard electrolytic capacitor. The lettering indicates the name or initials of the manufacturer. Below the manufacturer name is the capacitance value in µF, or microfarads, the number below the capacitance is the maximum voltage rating and the line or arrow indicates the positive terminal.
Markings on surface-mounted electrolytic capacitors are abbreviated. They are marked by a letter and followed by a three-digit number. The letter is the maximum voltage tolerance. The second two numbers followed by the number of zeros indicated by the third number is the capacitance. For example, E547 indicates a capacitance of 54 followed by 7 zeros, or 540000000. This is the capacitance in pF, or picofarads.