Siemens 6ES7540-1AD01-0AA0 Industrial Automation Module. Siemens 6ES7540-1AD01-0AA0 is the exact manufacturer order number for a industrial automation module in the SIMATIC S7-1500 portfolio. Siemens describes this exact reference as: SIMATIC S7-1500, CM PTP RS232 BA communications module for serial connection RS-232, freeport, 3964(R), USS, 19200 bit/s, 9-pin D-sub plug. The verified manufacturer lifecycle record is PM300: Active Product.