|
Post by madpatty on Mar 28, 2016 19:06:10 GMT -5
Hi Jet enthusiasts,
Does anybody know or has used a pressure teansducer to get a digital reading(data acquisition) using a arduino or some other form.
I am looking for a low cost pressure sensing device that i can use to get pressure readings to the computer.
Thanks.
|
|
witek
Member
Joined: January 2015
Posts: 18
|
Post by witek on Mar 28, 2016 21:14:37 GMT -5
I'm testing using a pair of cheap chinese ebay pressure transducers on my upcoming project. I bought a pair of these: www.ebay.ca/itm/G1-4-Pressure-Transducer-Sensor-0-1-2-MPa-for-Oil-Fuel-Diesel-Gas-Water-Air-/311440405505?hash=item48834b7401:g:L~MAAOSw0JpV7DDj&vxp=mtrThey provide decent readings it seems, though I do wish they were matched as they read a 2psi difference. Wiring them up is simple, one lead to ground, one to +5V and the other to whichever arduino input (analog in my case). I'm fairly new to the world of programming, but the code I'm using is this string: inputP1 = analogRead(A0); P1 = ((float)(inputP1-102)*175/818); With a delay of 500 at the end of the loop it seems to return decent results, though I'm still running it in parallel to regular analog gauges just to be sure until I can trust these more.
|
|
|
Post by madpatty on Mar 28, 2016 21:24:29 GMT -5
Thanks for the reply.
Do you know anything about the rpm sensors?
Thanks.
|
|
witek
Member
Joined: January 2015
Posts: 18
|
Post by witek on Mar 28, 2016 21:29:09 GMT -5
Thanks for the reply. Do you know anything about the rpm sensors? Thanks. I've got an omron e3x-a21 optical sensor pointed at a half white, half black compressor nut for my rpm reading. It too is plugged into the arduino. These pop up on ebay every now and then for either absurd prices or great deals. I managed to score mine for $20 (canadian) Seems there's a divide between two preferences on here. Some use the optical sensor while others use a hall effect sensor. The optical seems to work fine for most applications, though I hear some are worried about dirt on the sensor affecting readings.
|
|
|
Post by madpatty on Mar 28, 2016 21:34:20 GMT -5
|
|
witek
Member
Joined: January 2015
Posts: 18
|
Post by witek on Mar 28, 2016 21:35:30 GMT -5
|
|
witek
Member
Joined: January 2015
Posts: 18
|
Post by witek on Mar 28, 2016 21:47:08 GMT -5
I'm no expert (and could be wrong), but those look to be hall effect type sensors. Steve's code posted above also has schematics to get these types of sensors to work.
|
|
|
Post by parallaxattack on Mar 28, 2016 23:36:59 GMT -5
From my research down this road a couple months back, the eBay sensor linked above is a VR (variable reluctance) not Hall Effect sensor. On the Holset turbo's they read of a flat on the turbo shaft in the center housing. Hall sensors usually have 3 wire, VR sensors have 2. For a VR sensor you want to use something like MAX9924 to do the signal conditioning before trying to feed it into your microcontroller as they output an AC voltage that depends on speed ranging from a few mV at low speed to several 10's of V at turbine speeds. VR sensors need a ferrous (ie iron) target, Hall needs either a ferrous target if they have an internal magnet or an magnetic target if they don't.
IIRC the BorgWarner sensor is eddy-current with on-board signal conditioning that outputs an nice 5V squarewave. Eddy current can happily detect a non-ferrous target as long as it's conductive so they can sense aluminum or titanium compressor blades going by. I believe the BW sensors are actually made by Jaquet. As far as I've found it the BW sensor seems to be the only eddy current sensor readily available for any kind of reasonable price.
|
|
|
Post by madpatty on Mar 29, 2016 0:26:16 GMT -5
Thanks for the useful post.
|
|
|
Post by madpatty on Mar 29, 2016 9:53:12 GMT -5
Thanks for the reply. Do you know anything about the rpm sensors? Thanks. I've got an omron e3x-a21 optical sensor pointed at a half white, half black compressor nut for my rpm reading. It too is plugged into the arduino. These pop up on ebay every now and then for either absurd prices or great deals. I managed to score mine for $20 (canadian) Seems there's a divide between two preferences on here. Some use the optical sensor while others use a hall effect sensor. The optical seems to work fine for most applications, though I hear some are worried about dirt on the sensor affecting readings. Hi Witek, I just ordered a new omron e3x-a21 sensor. But i am not that good at electronics. But still i can DIY this stuff. How have you made this sensor to collect rpm readings. I will be using a NI mydaq for the data acquisition. What is the output type of these sensors.? Thanks.
|
|
witek
Member
Joined: January 2015
Posts: 18
|
Post by witek on Mar 30, 2016 8:03:14 GMT -5
I've got an omron e3x-a21 optical sensor pointed at a half white, half black compressor nut for my rpm reading. It too is plugged into the arduino. These pop up on ebay every now and then for either absurd prices or great deals. I managed to score mine for $20 (canadian) Seems there's a divide between two preferences on here. Some use the optical sensor while others use a hall effect sensor. The optical seems to work fine for most applications, though I hear some are worried about dirt on the sensor affecting readings. Hi Witek, I just ordered a new omron e3x-a21 sensor. But i am not that good at electronics. But still i can DIY this stuff. How have you made this sensor to collect rpm readings. I will be using a NI mydaq for the data acquisition. What is the output type of these sensors.? Thanks. Patty, To get a reading with the sensor you'll need an optical cable as well. There's a million different varieties of these, but the one I have is an omron e32-dc200e as it has a small head and was relatively cheap. It cost me a tenner on ebay. The signal these produce is an open collector type circuit, so you'll need a pull up resistor to bring the signal to 5v before the arduino will read it.
|
|
|
Post by madpatty on Mar 30, 2016 8:15:50 GMT -5
Hi Witek,
I am going to use a NI mydaq for all this data acquisition.
Does that also requires any signal conditioning? Or can be directly fed to the DAQ.
Thanks.
|
|
|
Post by madpatty on Mar 30, 2016 9:47:22 GMT -5
Witek,
Noob question alert. First time at electronics so please bear with me.
The output from the sensor is digital or analog?
Will i connect the signal wire from sensor to AI or DI/O?
Same question for borgwarner efr sensor.
Is it a digital output or analog output??
Thanks.
|
|
|
Post by parallaxattack on Mar 31, 2016 0:54:55 GMT -5
The Omron sensor is an open collector output, you want to connect a 10k or so resistor from the brown to black leads and measure your output from black to blue. The blue lead will then go low whenever the output is active, connect to a digital in.
|
|
|
Post by madpatty on Apr 11, 2016 3:34:23 GMT -5
Hi Electronic experts,
Today i wired the pressure transducer to the data acquisition device.
But unfortunately the output from the sensor was not as expected. Very noisy and also didn follow the linear relation of increasing output voltage with increasing pressure.
What can be done.
Thanks.
|
|