An image forming apparatus includes an image forming unit for forming an image on a recording medium, a command unit for commanding image forming conditions, a first switch for connecting a power source to the apparatus, a first detector for detecting an operational position of the first switch, a second switch for enabling the first switch to connect the power source to the apparatus, a second detector for detecting an operational position of the second switch, and a memory having microprograms stored therein for operatively controlling loads on the image forming unit. The operation of the image forming unit is controlled by signals derived from the first and second detectors and the microprograms.