S150 dropping out

HI guys

we are currently having trouble with a s150 drive.  it is dropping out and we have no idea why.  the only faults are dc undervoltage, line supply fault.

the engineers want to connect a PC up to it for some fault finding. 

we have the starter software

what sort of cable do I need

where to I hook it up

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Split from G150 communication with PC using Starter Software.

Hello,

one of answer you have in previous post, read pls that post.

I sought of need it spelt out for me, as my PC/ comms skills are weak, due to the fact that im and end user.

Is this x127 port on the cpu that is near the HMI, 

will it talk to the starter software, just throught Ethernet or do I need a PCM converter to talk in profibus

will the starter software offer any diagnostic help to as why the drive trips out.

          -the drive just shuts down, (HMI is still on, but the main contactor drops out.)

engineering help for me wasn't on over the weekend and wont be here today either.  every time the drive trips we have a environmental incident that needs to be reported to the EPA.

faults  VDC undervoltage