28 replies to this topic

[Mark]

Update:


Sensor uses a 12V VRef. The curve is linear:

1000mV = 0psi
5000mV = 2000psi

[Tom Hampton]

While not definative...I found this information on flyinmiata:

http://www.flyinmiat...h/stock_bpv.php

The same data can be found in this book:


How to Build a High-Performance Mazda Miata MX-5

By Keith Tanner


Unfortunately, I have not been able to find anything more authoritative.

[Mark]

Thanks Tom!

I have confirmation that the AIM MXL is producing regulated 5v and 12v reference voltages, I think the MSI has a built in VR though as its output does not vary over a 10-30v range. Todd, please report back!

[forestdweller37]

Thanks for all the research you folks are doing. I hope this MSI sensor has it's own VR. The VR IC's I've found from Digikey all like a higher input voltage vs. output. That's why I settled on 10 volts for my DL1.

[Todd Green]

I have confirmation that the AIM MXL is producing regulated 5v and 12v reference voltages, I think the MSI has a built in VR though as its output does not vary over a 10-30v range. Todd, please report back!

Here's the skinny I got:

M3431 - 5v, no Voltage Regulator
M3441 - 10-30v, with Voltage Regulator in the sensor, linear output of 1-5V

300 series is the same as the 340 series, just the diameter of the body of the sensor is larger (there are some other minor differences in packaging that don't apply to us etc. See the data sheet for full details.) They cost less, but I was't able to find anyone that carried the 2.5K psi sensor in 1/8 NPT. Mark you need to make your adaptor with 1/4" as well! The 300 series is only $105. Don't know if you can simply get a 1/4" to 1/8" adaptor at a hardware store that works with these pressures. I'm a software guy.

So long story short, if you want to run on 5v reference from your data acq, you need the "3" model. If you just want to run off the car's power (or any other 10-30V source), the unit Mark/ICM sells should work just fine. Good news.

Links to the two products (you can get the datasheets from there):

MSP340
MSP300

Oh and if anyone wants the wiring: red is input/source/reference voltage, black is ground, white is your 5v output (to data acq)

[Mark]

Todd,

Thanks for the info.

For those that need an adapter: McMaster 48805K252 looks like a good match.

The fitting is rated for 6600 psi so I think it will do. I'll stock a few so if someone needs one you can order one along with the adapter.

[Danny Steyn]

Todd,
I stand corrected on the psi. Checked two of my runs and see peaks nearing 800 psi max. Data is from a 99 SM if it matters.
Mark

Just north of 800 PSI , also '99

[Chris D.]

I am right in the middle of hooking my MSI brake pressure sensor up to my Traqmate. In reading the Traqmate manual, they state that you have to include a resistor in line with the voltage source (12V from the vehicle in my case). Has anyone else done this? Maybe I am not interpreting the manual correctly, but I'd sure hate to fry my new pricey little sensor.

BTW, the ICM adaptor is awesome....took all of 5 minutes to hook up.

[Muda]

Recently put an AEM brake pressure sensor in and hooked into traqmate. 5v, 1,000psi model. No resistor used. Set 0 at resting voltage, set 100 at full pressure voltage. Would take about 15 minutes except for the silly connector to the sensor.