The ID sensor is used to keep image density by changing the value of ID sensor standard, development bias, drum potential and LD power with Vsp and Vsg.

The ID sensor operates at the following times:

  1. When the machine has been unused beyond the time determined and the printed sheet count has exceeded the predetermined value.
  2. When the temperature and/or humidity has changed by more than a certain range, and the machine restarts the engine (i.e. the main power is turned on, warming-up after the fusing-off mode, and the front cover is closed.)
  3. When the machine is processing a job that has more than a set number of sheets (job is interrupted) or when the machine has completed a job that has the set number of sheets.