Splitting one signal from DAQ

Hi I m just working on my project and part of this is also build interface in Labview to use DAQ device 6008.
DAQ device serves to acquire Voltages from thermistors and my interface should split this signal for example like this:
=if(and(x>=8,D65<=8.54),-33.1*LN(D65)+46.12,if(and(x<8,x>=7.12),-40.1*LN(D65)+34.11,if(and(x<7.12,x>=6.15),-51.2*LN(D65)-0.28,"Out of Range")))
but this is just excel equation that works. I tried to do something similar in quation node because that would be the simpliest way for me, signal that enters the node is x and leave as y and goes to the waveform chart, but it didn`t work.
Then I built this interface thanks to the greater, lower icons and it was working fine till I was using number indicators icons as my input, but when i replaced them with DAQ device there was lot of issues with data types I was using and even after I fixed them there was all of sudden other problem with my equation node (because I needed to write condition somehow I used node) DAQ didn`t like it.
Any help please. I m new in this world then if someone will know what to do, please try it in simple world.
thank you in advance

Hi and thank you for your answer.
First file is the interface I created without DAQassist because I was told it will be the same when the numeric controllers will be replaced with DAQ assist, and this interface works.
The next file is with DAQassist and there is many errors regarding the wires types and even when I add "convert from dynamic data" after signal is split then I get next error, and even when I ad "index array" that is recomended for this error when I run simulation I m getting next error regarding my functional node.
If you can help I would really appreciate it.
I have to find my very first file which include only functional node and I will forward it to you.
Best regards
Tino
Attachments:
Tino_equation_node.vi ‏124 KB
Tino_equation_node_DAQ.vi ‏176 KB

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Im doing a project, where im driving 6 leds of different colours at different frequencies using the digital outputs of a usb-6009, and receiving a signal using a single photodiode using the analog input of the same usb-6009
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now i think we are getting somewhere
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Splitting one signal from DAQ

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