You are correct. There is no information on the TB Interlock signal. I'll create a KnowledgeBase to prevent any confusion in the future. I apologize for the inconvenience.
TB Interlock is indeed a terminal block line, designed in as a safety feature. If a terminal block is attached, then the line is pulled low. We do not currently use the feature; it is available for future use.
Note: The TB_Interlock line is pulled up on the PXI motherboard with a 20k resistor.
Hope this helps!
Switch Product Support Engineer
NI - USA
Message Edited by Chad PSE on 02-09-2009 09:06 AM