I have problem with Siemens RS 485 repeater. I installed additional interface module with one I/O card on the PROFIBUS network with following settings: PROFIBUS Baudrate 1500 kbps, Highest address station 126, Minimum station delay time 11tBit, Maximum station delay time 150 tBit, setup time 1 tBit.

When I download to CPU hardware configuration I get SF I BF leds on and I don’t see any of the bus members online. I tried to put in the PROFIBUS options to take into the consideration 1 repeater on the network, but I get same result. I even tried to change repeater, but without success. Since the longest line between CPU and IM module is around 100 m, I tried to connect it without repeater and I get PROFIBUS network online and both LEDs are off. But when I try to connect it (using set PG/PC interface with CP5611 communication PCI card) on the CP 5611 auto settings I get info about network and everything seems OK. When I switch to CP 5611 (PROFIBUS) and try diagnostic I get error message 0x031b “Synchronization error…”

I checked all termination resistors (swithces) and they are OK.

Please help, thanks!