Analog Sensor Setup for RCP3

All sensor specific discussions! Temperature, pressure, steering angle, brake and throttle, etc. Post adaptations of OEM-style sensors, and also your clever DIY hacks and custom designs here too!

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SwedishKnievel
Posts: 17
Joined: Mon Aug 29, 2016 9:23 pm

Analog Sensor Setup for RCP3

Post by SwedishKnievel »

I've looked through the website and have not found any documentation about setting up analog sensors. Here is what I have:

Oil Pressure - 0-100 psi 3 wire sensor
Oil Temperature - GM style with 2.2k pull up resistor
Coolant Pressure - 0-30 psi 3 wire sensor
Fuel Rail Pressure - 0-100 psi 3 wire sensor
Brake Pressure 0-150 bar 3 wire sensor
Fuel Level - factory in-tank wired with a 220 pull up resistor (measured full and empty resistance and calculated voltage at each level)
I know which analog channels each are on. I just am unclear how to configure each sensor in the app.

Is there documentation beyond the "Sensor Guide"?

In the analog sensor setup there are many options and frankly I don't know where to go next.

PS can I use my PC to configure all of this and then switch to my tablet to use as my dash or do I have to setup through the tablet?

Thank you

jpf11
Posts: 57
Joined: Wed Oct 23, 2013 9:42 pm
Location: United States

Post by jpf11 »

I think you're looking for these docs:
https://wiki.autosportlabs.com/RaceCapt ... ate_Sensor

jpf11
Posts: 57
Joined: Wed Oct 23, 2013 9:42 pm
Location: United States

Post by jpf11 »

You can configure things via whatever you like, and use any devices be it tablet/phone/pc for a dashboard. The devices you connect with read the configuration when they connect and you can modify and then write back to the RC Pro... or not. So yes you can do your configuration via a laptop, and this has no effect on the dashboard you set up on a tablet.

SwedishKnievel
Posts: 17
Joined: Mon Aug 29, 2016 9:23 pm

Post by SwedishKnievel »

Thank you. This is helpful. I got through a lot via trial and error. Also, working from my laptop helped a ton. One of the things that I did that moved me along was to simply monitor voltages to make sure everything was connected properly. Once I did this I found a wiring mistake. After the wiring was corrected I then worked at calibrating the sensors.

brentp
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Post by brentp »

Starting by confirming voltages is a good approach.

With the latest 1.12.x app, we also supply presets for the analog channels for a number of common sensors, which will make calibrating sensors closer to a plug and play experience:

Image
Brent Picasso
CEO and Founder, Autosport Labs
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SwedishKnievel
Posts: 17
Joined: Mon Aug 29, 2016 9:23 pm

Post by SwedishKnievel »

The presets certainly helped me understand more about how to calibrate the sensors.

brentp
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Post by brentp »

Awesome - That was a feature long in coming and should help dramatically. Glad it helped clarify!
Brent Picasso
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SwedishKnievel
Posts: 17
Joined: Mon Aug 29, 2016 9:23 pm

Post by SwedishKnievel »

Everything seems to be working great with the exception of the fuel level sender. This is what I have wired:

Image

Before I put the fuel sender in the tank, I connected it to a multimeter and measured the resistance with the float at the top (full - 2.6 ohms) and bottom (empty - 132 ohms). After dusting off my ohms wheel I calculated the following:

With a 220 ohm pullup resistor and +5v applied as above, I should have 0.58 VDC when the tank is full and 1.875 VDC when the tank is empty.

I then plugged these values into the RCP Analog Port configuration, and did not get the results I expected. Can anyone check my math on the above?
Last edited by SwedishKnievel on Mon Apr 09, 2018 9:03 pm, edited 1 time in total.

brentp
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Post by brentp »

Hi,

Can you post a screenshot of your analog calibration so we can review?

Also, you can switch your analog channel to 'raw' mode so you can monitor the voltage and prove you're seeing the correct voltage as your fuel level swings across the range.
Brent Picasso
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SwedishKnievel
Posts: 17
Joined: Mon Aug 29, 2016 9:23 pm

Post by SwedishKnievel »

I will get a screen shot up as soon as I can get to the car. I am not able to easily manually manipulate the fuel level sender as it is installed in the tank and a huge hassle to get to.

jpf11
Posts: 57
Joined: Wed Oct 23, 2013 9:42 pm
Location: United States

Post by jpf11 »

.058, not .58 when full.

SwedishKnievel
Posts: 17
Joined: Mon Aug 29, 2016 9:23 pm

Post by SwedishKnievel »

Here is what I have setup for fuel level. The trouble is that I don't believe (but don't really know) that there is 10 gallons of fuel in the car. It is entirely possible but I am not certain.

Image

Image

brentp
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Post by brentp »

The thing with fuel level senders is that they are typically not linear. So, the best way to map it is taking voltage readings at the OEM gauge (assuming the OEM gauge is conencted) at the following points:

* empty
* 1/4 full
* 1/2 full
* 3/4 full
* full

Then you can plug those values into the mapping grid. That should yield a much better response.

Hope this helps!
Brent Picasso
CEO and Founder, Autosport Labs
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