1 EXHIBIT 21.1 SUBSIDIARIES OF POWELL INDUSTRIES, INC. NAME OF DOMESTIC SUBSIDIARY STATE OF INCORPORATION - --------------------------- ---------------------- Delta-Unibus Corp. Illinois Powell Electrical Manufacturing Co. Delaware Powell Power Electronics Company, Inc. Delaware Powell-Process Systems, Inc. (Inactive) Utah Powell-ESCO Company Texas Unibus, Inc. Ohio Powell Energy Systems Inc. (Inactive) Nevada Transdyn Controls, Inc. California NAME OF FOREIGN SUBSIDIARY COUNTRY OF INCORPORATION - -------------------------- ------------------------ Powell Foreign Sales Corporation Barbados, West Indies