Connecting Dwyer SFI-100T-3/4-A711T to USB-2416

[Mackenzie Cox]

I have this flow rate sensor that I got from Dwyer and it included some instructions for set up, but I can't seem to get it to give me a reading without jumping a whole bunch. Can you guys tell me how to connect it properly?

[Fausto]

Hello @Mackenzie Cox.

Please provide a datasheet of the flow device to be used with the USB-2416.  Which software are you using with the USB-2416?  Please provide more information about your software and hardware application.

The following link is what I found, but would appreciate it if you could ascertain additional product information.  https://dwyer-inst.com/PDF_files/SFI100T_d.pdf

There's a 5 VDC output signal on the white lead, which is what you'll probably use as an input signal for the USB-2416.  The black lead is the ground, so you'll need to decide if you want to setup the analog input channels in single-ended or differential mode.  You'll need to find out from the manufacturer if the green lead is necessary for the flow measurements.  The red lead is the external power supply for the flow device.

The frequency output range is 0 - 100 Hz, which corresponds to the flow range of 3 - 35 GPM.  

Regards,

Fausto

[Mackenzie Cox]

I am using Labview to read everything. Here is the link to where we purchased it from https://dwyer-inst.com/products/flow/flow-transmitters/paddlewheel-in-line/seriessfi-100t.html.

There is an instruction manual on that page here: https://legacy.dwyer-inst.com/PDF_files/F_40.pdf?_gl=1*g8yor8*_ga*ODY3MjQ0NzMzLjE2OTA5NzcyNzI.*_ga_9H4TZPR8R2*MTY5MTA4MzQ4MS4zLjEuMTY5MTA4Mzc3MC4wLjAuMA..&_gl=1*g8yor8*_ga*ODY3MjQ0NzMzLjE2OTA5NzcyNzI.*_ga_9H4TZPR8R2*MTY5MTA4MzQ4MS4zLjEuMTY5MTA4Mzc3MC4wLjAuMA..

 

It has a few ideas for how to wire it up, but I have been unsuccessful at getting labview (or daqami, where I do the testing before I set it up in labview) to read it correctly. I had red to positive power supply, black to negative, and tried having green to CH H CH L or white to CH H or CH L and neither have been successful. I have the channel I am connecting it to calibrated for voltage.

[Fausto]

@Mackenzie Cox,

 

The second page of the 'Specifications - Installation and Operating Instructions' document contains the frequency to flowrate conversion formula, as well as the electrical installation.  

The USB-2416 has two event counter input channels, which will count pulses, but then you need to use a software timer to calculate the frequency (counts/second).  Once you have the frequency, then your vi example can use the frequency in the sensor's flowrate conversion formula.

Another option is to configure the USB-2416 analog input channels to differential (or single-ended) mode in InstaCal and then connect the black wire to the channel low screw terminal and/or the ground terminal, and the white wire to connect to the channel high screw terminal.  When you start acquiring, you will see the pulse train, but then you will need to use LabVIEW's signal processing vi's to determine the pulse frequency.  

Regards,

Fausto

[Mackenzie Cox]

Okay, I connected it with black to CHL and white to CHH and red to 24+. I am getting a roughly consistent value now, but you said this value is equal to the pulse train? How do you convert from the pulse train to the frequency?

[Mackenzie Cox]

I figured out how to wire the flow sensor using the counters, but cannot find a way for LabVIEW to reference the counter channels. Typically, you can use the MCC "Create Channel" block to call to the CHH and CHL pins, but I cannot seem to locate how to call to the counters.

Edited August 10, 2023 by Mackenzie Cox

[Fausto]

Hello @Mackenzie Cox.

Take a look at the 'ULx Meas Dig Period.vi' example found in the 'C:\Program Files\National Instruments\LabVIEW {version]\examples\ULx\Counter\Measure Period or Pulse Width.llb' file.

 

Also, look at the 'ULx Count Digital Events.vi' example found in the 'C:\Program Files\National Instruments\LabVIEW {version]\examples\ULx\Counter\Count Digital Events.llb' file.

 

Regards,

Fausto