Sinamics G120 VFD DI problem

Hey guys,

while this question is probably better suited to the Siemens support forums, they've been slow to correct the problem I'm having with my login so I figured I'd post here. Maybe someone has a quick response.

I'm using a Sinamics G120 with CU240E-2 PN-F and am having issues with the digital inputs when running with any macro that uses the I/O on the front of control panel. DI0, DI2, DI4 work fine, DI1, DI3, and DI5 do not. Applying 24V directly to the inputs and checking the CU DI status parameter I get nothing on those ports. Tried swapping control units, same result.

I was taking a wild guess that this might have something to do with the failsafe inputs combining DI0/1, DI2/3 and DI4/5, but none of the macros I was testing used F-inputs, unless there's something I'm missing.

Anybody who's worked with this drive/control unit know what might be going on? Is there some simple parameter setting I'm missing?

Thanks.

Seen that
There's a wire for the common (another one) you are forgetting
I don't have the manual I'm front of me for the terminal

JRW thanks for the response.

Interesting, I thought this might be the case but I connected the DI com pin to 0V along with the GND from the +10V analog supply, didn't see any other com. Will check it again and post back when I have the drive in front of me.

Problem solved, exactly as JRW said. Another DI COM (DI COM 2) was buried underneath the operator panel, and I overlooked it in the manual. Thanks.