ADC24: does it support NPN pulse (rpm) logging?

Which product is right for your exact requirements
Post Reply
sedex
User
User
Posts: 3
Joined: Wed Sep 22, 2021 3:10 pm

ADC24: does it support NPN pulse (rpm) logging?

Post by sedex »

I have an ADC24, and will record output from 8 hydraulic pressure transducers. I want to add 4 NPN type magnetic picks up to measure rpm of various shaft - and - in other locations, count the rotation of a pulley (just need a total count).

Before I spend cash on sensors, I just need to confirm if the ADC24 supports these types of pulse + calculation function.

If the ADC24 does not support this function, then would a scope eg 2000 be appropriate?

Finally, software and data logging: It would appear that I would need a separate raspberry pi to run each of the datalog (raspberian OS?) and picoscope (ubunto?) software - is that assumption correct?

Appreciate any feedback.
Brent

Gerry
PICO STAFF
PICO STAFF
Posts: 1145
Joined: Mon Aug 11, 2014 11:14 am

Re: ADC24: does it support NPN pulse (rpm) logging?

Post by Gerry »

Hi sedex,

Sorry for the delayed response.

Could you tell us the following:

What is the output of the NPN type magnetic pickups (would it be, for instance, an open collector, requiring a pull-up, or something else)?
What is the maximum pulse rate likely to be (and the duty cycle or pulse width)?
How long would you be measuring RPM for?

Unfortunately it's not possible to count pulses in PicoLog 6 so you can't calculate RPM. However, you can measure RPM in PicoScope 6, and once we know more about your intended application, we should be able to advise you regarding an appropriate PicoScope model.

We don't have PicoScope 6 Running on Raspbian (PicoLog Cloud 6 is on Raspbian though), but we do have both PicoScope 6 and PicoLog Cloud 6 both running on Ubuntu.

Regards,

Gerry
Gerry
Technical Specialist

sedex
User
User
Posts: 3
Joined: Wed Sep 22, 2021 3:10 pm

Re: ADC24: does it support NPN pulse (rpm) logging?

Post by sedex »

Gerry - appreciate the response. Diving into the online tutorials and Youtube, I have determined that the following should function:

Install the Picosope and Picologger software on a Win 10 mini PC with 2 LCD displays. These mini computers are tiny, low cost, and run off 12vdc so are ideal. If I need to use 2 PC then I can do that too so no constraint.

Use the 2204A for RPM from the hall effect sensors that is a common automotive function (I use automotive sensors in fact). RPM display for the 2 inputs can be displayed = problem solved.

ADC24 to pick up the raw pulse data from other hall effect sensors. These simply need to track (slow) pulses, and will be post processed in excel (edge detection for increase / decrease voltage change) so that should resolve that problem as well.

ADC24 will also be used to obtain data from a dozen linear pressure and temperature sensors and it is perfect for this role.

I am waiting delivery on the 2204A and will be installing all and testing over the next couple of weeks.

So for now it seems we have resolved the outstanding questions.

Cheers

Gerry
PICO STAFF
PICO STAFF
Posts: 1145
Joined: Mon Aug 11, 2014 11:14 am

Re: ADC24: does it support NPN pulse (rpm) logging?

Post by Gerry »

Hi Sedex,

Yes that would work if you're given RPM, and if you use Excel to count edges. Glad you found your solution (just make sure that you're aware of limitations due to the ADC conversion times).

Just out of curiosity, what sort of spec are the mini PC's?

Regards,

Gerry
Gerry
Technical Specialist

sedex
User
User
Posts: 3
Joined: Wed Sep 22, 2021 3:10 pm

Re: ADC24: does it support NPN pulse (rpm) logging?

Post by sedex »

Gerry - This is a typical unit – there are literally dozens on Amazon in the US$250 to US$350 range and the big box stores also list many others.

Kamrui Mini PC Windows 10 Pro,

8GB RAM/128GB SSD Mini Desktop Computer Ιntel Celeron J3455 Processor, Quad Core Micro Computer 4K, Support mSATA, 2.5-inch SSD, 2.4G/ 5.0G WiFi, Gigabit Ethernet, HTPC

2 x USB 2.0 ports, 2 x USB 3.0 ports, 2 x HDMI 2.0 ports, 1 x Gigabit Ethernet port, 1 x Micro SD Card port, Supports Auto Power On, RTC Wake Settings and Wake On LAN.
‎5.04 x 5.04 x 2.05 inches

While this runs windows, after we have determined the final configuration, we will likely switch to Ubuntu. My requirements are that these unit must operate without any operator input (locked down) and we are able to 100% control what gets auto load / start when power on, eliminate pop up windows of all types, and lock it down from doing silly things like phoning home and auto update – all of which Windows loves to do and are increasingly difficult to manage.

Windows Assessment and Deployment Kit (Windows ADK) offers an alternative, as does Windows IoT Core, but for small companies Ubuntu offers better economics, control and a lot less fuss and bother (lot more programmers available too!).

It would be interesting to know if the Win - IoT Core is supported by Pico software?

While the picoscope and picolog software are not fully optimized for Ubuntu, we can work around that with the SDK and / or write something that will use the raw data and do the minimal amount of math functions that we need. Most of our output can be post processed.

So overall we feel that the Pico line of products and existing software will provide a solid base on which to build out and get to market fast (we need to get out there – perfection can wait). If it supports IoT Core that would open other avenues for future expansion, but it may be cheaper / faster / easier to complete the Ubuntu development (nudge nudge....)

Cheers

Post Reply