6ES7590-0BH00-0AA0 SIMATIC S7-1500 / ET 200MP active backplane bus 8 slots for inserting S7-1500 I/O modules for hot swapping for use in the ET 200MP with IM 155-5 PN HF (from FW V4.4.1); S7-1500 mounting rail and slot covers to be ordered separately