The ACM-24AT includes 24 red status lights, 24 yellow fault lights, 24 buttons for manual control, one system fault light, and one "online/power" light. It also has a local piezoelectric buzzer for ACM-24AT alarm and audible indication in case of fault status. In addition, there is a mute/confirm button. AEM-24AT is an expansion card of ACM-24AT, with the same appearance as ACM-24AT. Except for the mute/confirm button, system fault light, and "online/power" light, which do not work, it
It has the same function as ACM-24AT.