the difference between sourcing and sinking of ouput/input type

[shh2745]

Dear Guys:

I am working on a project with cFP. I just found that there are two different types of input/output signals with sourcing and sinking in the cFP module. Can anyone tell me what's the difference between sourcing and sinking?  I would really appreciate your help. Thanks.

My output requirement is discrete signal with 120 VDC and 5A. 

Best Regards.

Fred

[bogdani]

Hi

I think thia will be enought: http://zone.ni.com/devzone/conceptd.nsf/webmain/0DDBBEEDF2365A3486256E66007F6C26?opendocument

bogdani