topic Logical export in Lookout

Logical export

Randall1 — Thu, 26 Sep 2002 00:08:21 GMT

In Lookout when I go to Historical data viewer and select a view to export, that is a logical value that is a switch, when I look at the text of the export all
the values are just opposite of the real value of the switch. That is at the time it said the switch was OFF
it was actually ON. Why is this?
Thanks

Re: Logical export

Mike S. @NI — Thu, 26 Sep 2002 20:34:58 GMT

Randall1,
Thank you for using the Discussion Forums here at ni.com. The most likely reason for this behavior is that the "invert logical signal" checkbox has been checked. To verify this, open the data member configuration window for the switch in question. When you choose this checkbox, an ON value is represented by an OFF value, and so on. When you do not select it, ON is ON and OFF is OFF. This information can be found in the Lookout help files, under "edit logical data members."

Regards,
Michael Shasteen
Applications Engineer
National Instruments
www.ni.com/ask

Re: Logical export

Randall1 — Fri, 27 Sep 2002 02:49:56 GMT

I did look, and the box is unchecked. I also have a HyperTrend on the same Panel and it follows the switch. If flip the switch up the HyperTrend trace moves up, when I flip the switch down the HyperTrend trace moves back down. But the export ASCII file for the switch shows it is ON when it shows to be OFF in the HyperTrend and the switch on the Panel. If I put a check in the "invert logical signal" the HyperTrend now shows a low when the switch on the panel is ON and the export file now shows it to be ON.
At this point the export file is now following the switch positions but the HYperTrend
Is now backwards. The output to the PLC does not change if the check box is checked
Or not it always follows the switch position on the Panel. I have a logical base p
osition
Of 0 and a Logical True height of 50 in the HyperTrend. Whats up?
Thanks