These diodes are used to convert AC into DC these are used as half wave rectifier or full wave rectifier. Three points must he kept in mind while using any type of diode.

  1. Maximum forward current capacity
  2. Maximum reverse voltage capacity
  3. Maximum forward voltage capacity

The number and voltage capacity of some of the important diodes available in the market are as follows:

  • Diodes of number IN4001, IN4002, IN4003, IN4004, IN4005, IN4006 and IN4007 have maximum reverse bias voltage capacity of 50V, 100V, 200V, 400V respectively and maximum forward current capacity of 1A.
  • Diode of same capacities can be used in place of one another. Besides this diode of more capacity can be used in place of diode of low capacity but diode of low capacity can not be used in place of diode of high capacity.For example, in place of IN4002; IN4001 or IN4007 can be used but IN4001 or IN4002 can not be used in place of IN4007.The diode BY125made by company BEL is equivalent of diode from IN4001 to IN4003. BY 126 is equivalent to diodes IN4004 to 4006 and BY 127 is equivalent to diode IN4007.