Skip to main content
Electronic Theatre Controls Inc

What is the Curve on a CE (European) Sensor Module Breaker?

  • Prior to 1998 all breakers were D curve.
  • Since 1998 all single pole breakers have been changed to C curve.
  • From 1998 to 2009 all double pole breakers were still D curve.
  • Since 2009, all CE breakers (Single Pole, ND, RCD) have been C curve.
  • C & D Curves are defined by a European Standard. A is the fastest curve, D is the slowest.


The curve letter describes the trip time/current for overcurrent tripping.  It is an important parameter for installers.

  • Was this article helpful?