KISS Pitot bench design

[Nick]

Some more things to consider. I found the application notes on the MPX5010dp on the free scale site. And the ANI1646 about Decoupling caps. Read:



One thing that caught my eye was how you supply voltage to this thing. I don't think I can supply voltage to the Dataq unit because it runs on the serial port. So, if it has to have it's own power supply, how do I make sure it stays the same all the time. Would using batteries for this be better than a wall plug? If the voltage in varies so will the voltage out. Any thoughts as to how to deal with this? Perhaps the Dataq unit has a power out let for this kind of situation. I'll look into that.
Is there a good wall plug to use that does not fluctuate with house power? The one I have is just a universal type you would find at radio shack. 1.5v-12v


This is great fun!


Nick

If you get tired of educating me let me know.

[blown928]

You'd use a voltage regulator, like a 7805, with a .1 uf cap on the input and the output. Bring power in from the wall wart and power out will be a stable, regulated 5v.

[blown928]

[bruce]

Is this the type of valve you are refering to?



RV stores have them as "waste valves" usually black or grey. My local hardware store has 2" and 3" (white ones) for under $20 last I checked (which was earlier this year).

[Thomas Vaught]

I have used the Waste valves both as "bleed valves" and as flow control valves (when used in pairs. Imagine Bruce's threaded rod opening two
valves next to each other vs just the one.

Agree, for years I have bought the single valve unit with seals for under $20.00

Tom V.

[Mouse]

This is a Flow Performance 3" PWM valve. The Flow Performance FP1 can control it to achieve a selected test pressure.

These valves are also available without the motors for manual control via a cable or what ever.

[Thomas Vaught]

If you have the FP1 unit then getting the FP 3" PWM makes all the sense in the world. Let the FP1 and PWM keep the test pressure where you want it.

Tom V.

[blown928]

[blown928]

[Nick]

I have all the parts to make this thing work now. The Dataq is a cool deal. Real time on screen display, for $99 you can export it to excel in real time. That's the good news. The bad is I played with this thing for a few hours and cannot get it to do anything. I thought maybe the caps were in wrong so I hooked it up without them. Still nothing. Perhaps i don't know how to wire the sensor correctly.

Here is how I did it. "V out" to dataq "Ground" shared with battery and dataq. "VCC" Regulated 5V.


There are 6 pins, any Idea how to wire it?

"V out" "Ground" "VCC" "V1" "V2" "VEX"

The Dataq works. I put 9v to it and it shows up on the screen.

Anyone have any ideas. Other wise this deal is dead!

Nick

Hello anyone

[Nick]

Hello

[blown928]

[Nick]

Yep I used the regulator, and I tested it with my voltmeter. That works. This sensor is a MPX5010DP. I hooked the Vout to the dataq. The ground to the same ground as the sensor and battery. And VCC is the power from the regulator. The sensor shows the same volts in as out to the dataq. It does not change when you apply vacuum or pressure.

I am starting to think the VCC in not power to the sensor. I tried looking at free scale for a schematic for how it is to be used but could not find one. Perhaps there is more to making this work than what I thought. The other 3 pins must do something?


Thanks

Nick

[blown928]

[color=#000000]It's starting to shape up. The front panel's not on yet, and I'm still waiting for the top to be cut, but I powered it up for the first time today. I'm starting with 4 motors, but there's room for 8 more. The control box (red, on top) has switches for each motor and the speed control knob for the one speed controlled motor.




I brought power in through the rear panel with a 50A 220V range connector, and used 3 ground strips for power distribution. I still need to neaten up the wiring after the top is installed.


The motors mounted nicely in 4" holes with a couple pieces of angle iron. I still have to install the Rocco valves

[blown928]

I'm still waiting for the top to be cut, expecting it today. This weekend I added some styrofoam insulation to help quiet it down. Those 16-1234's are noisy little buggers!