Siemens Simatic S7-400 - Manual (Page 382)

Interface Modules
6-20
S7-400, M7-400 Programmable Controllers Module Specifications
A5E00069467-07
Operator Controls and Indicators on the Send IM
EXTF LED
(red) Lights up in the event of an external fault Line 1 or line 2 is faulty
(terminator missing or broken cable)
C1 LED
(green) Line 1 (via front connector X1, connection 1) is correct.
C1 LED
(flashing
green) An EU in the line is not ready for operation because
•
The power supply module is not switched on or
•
A module has not yet completed the initialization process
C2 LED
(green) Line 2 (via front connector X2, connection 2) is correct.
C2 LED
(flashing
green) An EU in the line is not ready for operation because
•
The power supply module is not switched on or
•
A module has not yet completed the initialization process
Operator Controls and Indicators of the Receive IM
INTF LED (red) Lights up if a rack number > 21 or = 0 was set.
Lights up if you have changed the rack number under voltage.
EXTF LED (red) Lights up in the event of an external fault (line fault, for example, if
the terminator is not inserted or if a module has not yet completed
the initialization process, or if the CC is switched off)
DIP switch DIP switch to set the number of the mounting rack.
Front connector X1 Upper connector (input) for the connecting cable from the previous
interface module.
Front connector X2 Lower connector (output) for the connecting cable to the next
interface module or for the terminator.