Turn on suggestions
Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type.
Showing results for
Topic Options
- Subscribe to RSS Feed
- Mark Topic as New
- Mark Topic as Read
- Float this Topic for Current User
- Bookmark
- Subscribe
- Mute
- Printer Friendly Page
Reading Square Waves using PCI-MIO-16E-4
Kevin SBU
Member
11-24-2004 09:42 PM
Options
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report to a Moderator
I am a mechanical engineer student from Stony Brook University. I am currently working on a project which uses a SwissFlow 800 flowmeter which has the following specs:
flow range* : 0,3 – 20 liter/min
interchangeability** : ± 2.25 %
accuracy : ± 1.00 %
reproducibility : ± 0.30 %
output : 100 to 2000 Hz;
square wave on – off
sensitivity K : aprox. 6000 pulses
excitation : 5 to 24 VDC, 12 to 24 mA
power consumption : 12 – 36 mA
process connections : 3/8” hose barb; 3/8”BSP Male
electrical termination’s : 3-wire flat cable sealed in housing, 15 cm
I need the connect this sensor to the PCI-MIO-16e-4 card and be able to count the pulses from the flowmeter using labview. So far I have connected to the analog input and only read a constant 5v reading from the DAQ. IS there anyone who can help me with this dilemma ? thank you very much.
Kevin Cheung
flow range* : 0,3 – 20 liter/min
interchangeability** : ± 2.25 %
accuracy : ± 1.00 %
reproducibility : ± 0.30 %
output : 100 to 2000 Hz;
square wave on – off
sensitivity K : aprox. 6000 pulses
excitation : 5 to 24 VDC, 12 to 24 mA
power consumption : 12 – 36 mA
process connections : 3/8” hose barb; 3/8”BSP Male
electrical termination’s : 3-wire flat cable sealed in housing, 15 cm
I need the connect this sensor to the PCI-MIO-16e-4 card and be able to count the pulses from the flowmeter using labview. So far I have connected to the analog input and only read a constant 5v reading from the DAQ. IS there anyone who can help me with this dilemma ? thank you very much.
Kevin Cheung
Dr._Imad
Active Participant
11-29-2004 10:06 AM
Options
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report to a Moderator
usually you buy a signal conditioner to convert the pulses to a 0_to_5 V, 0_to_10V, or 4_to_20 mA.
Then you can analog-read the signal properly.
or you can wire the signal (assuming it is TTL compatible) to a counter channel and read the pulse rate (frequency corresponding to some flow rate). several examples are shipped with labView that reads frequency.
Then you can analog-read the signal properly.
or you can wire the signal (assuming it is TTL compatible) to a counter channel and read the pulse rate (frequency corresponding to some flow rate). several examples are shipped with labView that reads frequency.
JaredA
NI Employee (retired)
11-29-2004 08:05 PM
Options
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report to a Moderator
The device you are using is supported under DAQmx. If you are using a API that supports DAQmx such as LabVIEW 7.x, then I suggest using a program that is written using the NI-DAQmx driver.
The next step that you should do is determine what type of signal it is that you are going to be acquiring. Is it going to be analog? If so, what is the range of the signal (i.e. 0..10 V, -10..10 V, etc.). You will then want to use a shipping example which will be installed when you install NI-DAQ. If you are using LabVIEW, you can view the examples by selecting Help from the LabVIEW menu and then selecting Find Examples. This will launch the LabVIEW Example Finder at which point you would want to locate an Analog Input example under the Hardware Input and Output directory.
Once you have the example that you wish to use, then confirm that you have the appropriate signal connections made. You can confirm that you are connected to right pins by viewing the pinout of your device. You can locate the pinout by finding the manual located at ni.com/manuals.
If it is not an analog signal that you are trying to acquire, but rather a digital signal that is TTL compliant, then you may consider using a counter example to acquire pulse counts or frequency measurements. Again I point you to the example finder and the device manual.
In regards to seeing a flat 5 V, this typically means that you have a floating signal and the A/D is railed at the maximum range setting. Check your physical connections, your voltage range, and your terminal configuration (Differential, RSE, NRSE).
Best of luck.
Jared A
The next step that you should do is determine what type of signal it is that you are going to be acquiring. Is it going to be analog? If so, what is the range of the signal (i.e. 0..10 V, -10..10 V, etc.). You will then want to use a shipping example which will be installed when you install NI-DAQ. If you are using LabVIEW, you can view the examples by selecting Help from the LabVIEW menu and then selecting Find Examples. This will launch the LabVIEW Example Finder at which point you would want to locate an Analog Input example under the Hardware Input and Output directory.
Once you have the example that you wish to use, then confirm that you have the appropriate signal connections made. You can confirm that you are connected to right pins by viewing the pinout of your device. You can locate the pinout by finding the manual located at ni.com/manuals.
If it is not an analog signal that you are trying to acquire, but rather a digital signal that is TTL compliant, then you may consider using a counter example to acquire pulse counts or frequency measurements. Again I point you to the example finder and the device manual.
In regards to seeing a flat 5 V, this typically means that you have a floating signal and the A/D is railed at the maximum range setting. Check your physical connections, your voltage range, and your terminal configuration (Differential, RSE, NRSE).
Best of luck.
Jared A
