Maxisemi D/I are digital static converter units for speed control of DC motors. Using the Minisemi D control electronics, the Maxisemi D/I offers an extended power range thanks to the use of larger thyristors in armature and field circuit. Maxisemi D/I are available for 1 and 4-quadrant operation and for supply voltages of 400VAC, 500VAC, 690VAC, 800VAC and 1000VAC. The type series offers output currents from 1000A DC to 4000A DC. Maxisemi D/I are available in two versions: either as basis equipment without switchgears and mains choke (according to the Minisemi D) or as complete unit ready for installation.