Hi,
I have a flow meter from the provide Analog Output between 0-5V.
Initially I had connected the output signals to NI9202 module between AI+ and COM believing I needed only AI+ and COM to get a reading. But the reading was fluctuating between 0 - 100% and never showed a steady value.
Later, I connected according to Single-Ended Connections shown in Getting Started Guide. i.e and the reading are somewhat steady. But my professor is not sure whether the signal is completely noise free or not.
The pin connection on my flow meter as per manufacturers as follows.:
Pin 1: Signal & Power Negative (12VDC)
Pin 2: Analog o/p Volt.
Pin 3: Power +ve (12VDC)
Currently I have connected Pin 2 to AI+ and Pin 1 to both COM and AI- (i.e similar to Single ended connections in the Getting Started guide).
My doubt is, do I need to add a 1M Ohm resistor on the line going to COM? (i.e same as Floating Differential Connections shown in the Getting started Guide). Will this provide any further reduction in noise?
When does one decide to use Single ended or Floating Differential Connections?
Thanks in Advance.
Link to the Getting Started Guide for NI-9202 http://www.ni.com/pdf/manuals/378030b.pdf
