Wind Sensor

Guest
I am trying to test the following wind sensor. I hooked up the sensor to the micro.

http://www.inspeed.com/anemometers/vortex_wind_sensor.asp

Since, I have no wind in the lab. SO, I thought that might test it with the following DC fan

http://www.digikey.com/product-detail/en/SG40281B1-000U-S99/259-1635-ND/2356497


The problem is that the DC fan produces 25.6CFM and the wind sensor gives output in response to miles per hour wind speed. I will mount the fan near to the wind sensor as close as possible with out any duct or anything.

My question is that how much wind speed this DC fan will produce in miles / hour or how can I convert the CFM into miles/hour?

John
 
m.john.khan@gmail.com wrote in news:51da9b37-2e9c-453a-8b96-
8c618e3b9d1f@googlegroups.com:

> http://www.inspeed.com/anemometers/vortex_wind_sensor.asp

Find the radios to the center of the cups and fins circumference, say in
inches. That is what it travels per pulse. Count the pulses per minutes =
total distance in min., then convert to foot, mile and hour, that is your
mile per hour wind speed.


--- news://freenews.netfront.net/ - complaints: news@netfront.net ---
 
I already did the car ride.I want to do it in the lab. with the DC fan. It would be so cool. Any solutions!
 
On Thu, 19 Nov 2015 14:34:02 -0800 (PST), m.john.khan@gmail.com wrote:

I am trying to test the following wind sensor. I hooked up the sensor to the micro.

http://www.inspeed.com/anemometers/vortex_wind_sensor.asp

Since, I have no wind in the lab. SO, I thought that might test it with the following DC fan

http://www.digikey.com/product-detail/en/SG40281B1-000U-S99/259-1635-ND/2356497


The problem is that the DC fan produces 25.6CFM and the wind sensor gives output in response to miles per hour wind speed. I will mount the fan near to the wind sensor as close as possible with out any duct or anything.

My question is that how much wind speed this DC fan will produce in miles / hour or how can I convert the CFM into miles/hour?

John
Click to expand...

Take it for a ride in the car!
 
On Fri, 20 Nov 2015 10:26:58 -0600, Tim Wescott
<tim@seemywebsite.com> wrote:

On Thu, 19 Nov 2015 14:34:02 -0800, m.john.khan wrote:

I am trying to test the following wind sensor. I hooked up the sensor to
the micro.

http://www.inspeed.com/anemometers/vortex_wind_sensor.asp

Since, I have no wind in the lab. SO, I thought that might test it with
the following DC fan

http://www.digikey.com/product-detail/en/SG40281B1-000U-S99/259-1635-
ND/2356497


The problem is that the DC fan produces 25.6CFM and the wind sensor
gives output in response to miles per hour wind speed. I will mount the
fan near to the wind sensor as close as possible with out any duct or
anything.

My question is that how much wind speed this DC fan will produce in
miles / hour or how can I convert the CFM into miles/hour?

Your fan is _rated_ at 25.6 CFM, but will _actually produce_ lots of
different flows.

Do you have a car with a spedometer? Can you put together a lash-up
that'll work in the car? Do you have any friends?

The classic 20th century amateur method for measuring wind speed is to
take your anemometer out on a calm day and drive around, comparing
readings between your spedometer and your anemometer. Preferably you'll
pick a stretch of road and drive back and forth, to more or less cancel
out the effects of wind.

Cars are a great resource for investigating aerodynamic problems that
occur at or below the speed limit.
Click to expand...

I imagine one would need to extend the sensor on a pole,
well out from the body of the car (maybe 1-2 feet), to get
readings such that air speed corresponds to vehicle speed.

Close to the body, there will be all sorts of issues from
turbulence and Bernoulli effects. (All that air that
impinges on the frontal area of the car has to go
somewhere!)

Best regards,



Bob Masta

DAQARTA v8.00
Data AcQuisition And Real-Time Analysis
www.daqarta.com
Scope, Spectrum, Spectrogram, Sound Level Meter
Frequency Counter, Pitch Track, Pitch-to-MIDI
FREE 8-channel Signal Generator, DaqMusiq generator
Science with your sound card!
 
For $12.99, you can buy this to calibrate your wind source:
http://www.tmart.com/NENETECH-GM816-Mini-Pocket-size-Digital-Anemometer_p210716.html?utm_source=newsletter&utm_medium=email&utm_content=EDMNov22-up4&utm_campaign=1122-2015-up4&oplk
 
Can you advise how can I use this Anemometer to calibrate the Wind Sensor?
 
m.joh...@gmail.com wrote:

Can you advise how can I use this Anemometer to calibrate
the Wind Sensor?
Click to expand...

** Think you need to get outdoors on a windy day.

Small, indoor fans generate too much turbulence for a reliable air speed test.


.... Phil
 
On Fri, 20 Nov 2015 07:33:30 -0800 (PST), George Herold
<gherold@teachspin.com> wrote:

On Thursday, November 19, 2015 at 5:34:12 PM UTC-5, m.joh...@gmail.com wrote:
I am trying to test the following wind sensor. I hooked up the sensor to the micro.

http://www.inspeed.com/anemometers/vortex_wind_sensor.asp

Since, I have no wind in the lab. SO, I thought that might test it with the following DC fan

http://www.digikey.com/product-detail/en/SG40281B1-000U-S99/259-1635-ND/2356497


The problem is that the DC fan produces 25.6CFM and the wind sensor gives output in response to miles per hour wind speed. I will mount the fan near to the wind sensor as close as possible with out any duct or anything.

My question is that how much wind speed this DC fan will produce in miles / hour or how can I convert the CFM into miles/hour?

John

You want to use the fan to calibrate it? I don't think there will be any good
conversion. It will depend on how the air can spread out.
How close they are to each other.
You could make some sort of wind tunnel to keep the air flow constant,
and then drop bits of paper into the stream and measure veleocity
with a video camera.. .but that sounds like too much work.

George H.
Click to expand...

Positive displacement would work, namely a piston in a tube. But not
for long.

Build a carousel!
 
I ran into some bouncing problems of the switch inside the Wind Sensor. I am using the following sensor

http://www.inspeed.com/anemometers/Vortex_II_Wind_Sensor.asp


I used some de-bouncing circuitries like the following circuit but still not able to get a stable reading

+5v
|
R 100k
|
|_____R_10k______VOUT----->> micro
| |
| |
\SWITCH( _|
| - Capacitor ( 100nF)
| |
|gnd |gnd
 
On Wednesday, December 2, 2015 at 1:43:59 PM UTC-5, m.joh...@gmail.com wrote:
I ran into some bouncing problems of the switch inside the Wind Sensor. I am using the following sensor

http://www.inspeed.com/anemometers/Vortex_II_Wind_Sensor.asp


I used some de-bouncing circuitries like the following circuit but still not able to get a stable reading

+5v
|
R 100k
|
|_____R_10k______VOUT----->> micro
| |
| |
\SWITCH( _|
| - Capacitor ( 100nF)
| |
|gnd |gnd
Click to expand...

Do you have a scope and can you post a trace?
I'm guessing you have the reed switch option and not the hall sensor.

George H.
 
Yes. I have the reed switch option. It looks good on the scope. But I do not get good readings with my program. Its like sometimes at high wind speeds I get zero mph SO, I want to make sure that at least analog circuit is working fine.
 
Hi,

I got the following Wind sensor with hall effect sensor.

http://www.shop.inspeed.com/Vortex-II-Wind-Sensor-with-Hall-Sensor-V2Hall.htm

Does it require debouncing ciruit too?
 
Hi,

Should I use a an external rising edge clock triggered flip flop to do this?
 
I am interfacing it to the Digital I/O pin of the micro. with a pull up resistor of 10Kohms. The sensor has three wires one for power (+5v), one is grounded and third one is pulled up via 10k resistor and connected to the digital I/O pin of the micro
 
In article <afab6630-a6f3-4f4f-92d9-1b07f14c910e@googlegroups.com>,
m.john.khan@gmail.com says...
Hi,

Should I use a an external rising edge clock triggered flip flop to do this?
Click to expand...

It all depends on what you're driving?

The flip flop will make the signal 50% duty cycle but it
will also give you only half the pulses.

Like I said, I don't know how you are interfacing it?

You could use a Freq to Analog converter chip, they're out
there..

Jamie
 
In article <67665b91-a97a-44e1-bce5-31af28e16a7d@googlegroups.com>,
m.john.khan@gmail.com says...
Hi,

I got the following Wind sensor with hall effect sensor.

http://www.shop.inspeed.com/Vortex-II-Wind-Sensor-with-Hall-Sensor-V2Hall.htm

Does it require debouncing ciruit too?
Click to expand...

If mechanical switch bounch is what you're referring to? The
HALL sensor will not need a debouce circuit.

Thinking back to your earlier post, me thinks that you could be
having other issues?

Monitoring a signal and removing random switch noise during switch
make and break periodes can be sorted out in code land. I assume you are
doing this in code?

In code you would have a timer "Time Off Delay" each time the switch
makes and when it breaks the Time OFf Delay would then start to could
down. If for some reason switch makes before the timer expires, then the
timer is reset back to the start again.

It's my guess that a simple cap on the input driven via a R from the
source should be enough? It saves in code writing but what ever.

Maybe your problem is speed? Rotation to fast for switch or processor
can not handle input speed? It's posible to miss a pulse on a uC if you
are not using triggered and latched type inputs.

A IRQ handler, a non maskable type, is great for this purpose.

Jamie
 
In article <26a9620e-439a-4244-b6c5-e556090aa939@googlegroups.com>,
m.john.khan@gmail.com says...
I am interfacing it to the Digital I/O pin of the micro. with a pull up resistor of 10Kohms. The sensor has three wires one for power (+5v), one is grounded and third one is pulled up via 10k resistor and connected to the digital I/O pin of the micro
Click to expand...

All you need to worry about is not to over drive your uC IO inputs.

Not sure if the sensor has a high side output but if it gets powered
from anything higher than your uC supply, you better take care to
clamp the input or scale it to proper levels for your uC.

You don't need a flip flop or any external clean up components, you
should be able to do all of that in CODE.


Jamie
 
On 2015-12-04, m.john.khan@gmail.com <m.john.khan@gmail.com> wrote:
> I am interfacing it to the Digital I/O pin of the micro. with a pull up resistor of 10Kohms. The sensor has three wires one for power (+5v), one is grounded and third one is pulled up via 10k resistor and connected to the digital I/O pin of the micro

do your debounce in software.

eg: don't accept a change of state as real until you've seen 10
consecutive instances of the new state. (each being on an separate instance of an interrupt)



--
\_(ツ)_
 
I am looking to calibrate my ADXL 335B accelerometer for just single x axis tilt. I was wondering that is there any accelerometer device out there that can provide with single axis tilt measurements with display that I can use to calibrate my device.
 
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