Size of a Mylar Capacitor

Discussion in 'General Electronics Chat' started by abuhafss, Dec 6, 2014.

  1. abuhafss

    Thread Starter Active Member

    Aug 17, 2010

    I can find various sizes of Mylar Capacitors with similar rating.
    For example 1.5µF,
    I can find bulky capacitors rated 500V, 650V or 700V (30 to 40mm x 20 to 25mm x 10 to 15mm)
    and also I can get smaller caps rated 450V or 500V (20mm x 15mm x 5mm).

    Does the size matters? I need to use them in CDIs at 300V. :confused:
  2. shortbus

    AAC Fanatic!

    Sep 30, 2009
    If your measured voltage is 300V, you need to use a higher voltage rated capacitor. A "rule of thumb" is two to three times circuit measured voltage. Have a look here -