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What data would you acquire with this?

OwainM — Tue, 28 Jul 2026 13:13:32 GMT

We're appraising the NI USB-6421 for a RoadTest and would appreciate some member input.

It's USB Type-C powered and has analogue and digital IO and 4 counters, analogue input channels with four input range settings between ± 200 mV to ± 10 V. The analogue output channels have an update rate of 250 kS/s/ch at up to ± 10 V.

It's compatible with some free data acquisition software from NI, but also has some professional software to use with it that's also available.

The full product specifications are available below:
[View:/cfs-file/__key/communityserver-discussions-components-files/14/usb_2D00_6421_5F00_and_5F00_usb_2D00_6421_5F002800_oem_29005F00_specifications_5F00_2026_2D00_07_2D00_28_2D00_13_2D00_47_2D00_51.pdf:1050:400]

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Thanks for reading and commenting below

RE: What data would you acquire with this?

cstanton — Wed, 05 Aug 2026 23:39:05 GMT

If you're interested in this hardware, you need to look in the NI group where you can engage with ni staff posting forum threads and blog posts about the kit and ask them any questions.

How to Turn a Button On with Python and mioDAQ

Flexlogger and mioDAQ Short

RE: What data would you acquire with this?

saramic — Sun, 02 Aug 2026 23:40:57 GMT

that's a lot of inputs, only thing that comes to mind is a smart, multi cell, of varied history battery like I am building parts of for EZ - EV challenge - Vape Cell EV. I have a lot of different unused vape cells I want to monitor, not only for CC/CV charging, but also their heat, charge and discharge rates and give them each an overall "quality" score. My prototype will probably only be a few cells but with something like this I could easily extend it to a few more.

RE: What data would you acquire with this?

stanto — Fri, 31 Jul 2026 22:00:21 GMT

It's not clear to me what I'd do with this exactly, or more so, I think I'd need lower level access to hardware that I have to do it justice?

It's the kind of hardware that means you can real-time log and over time monitor values isn't it? So I might have it sat connected up to say, a Raspberry Pi monitoring sensor outputs, regulated power, ripple/noise, characterising batteries - but I don't exactly have prototype boards.

Perhaps this would be something useful to people who make conference badges and the like?

RE: What data would you acquire with this?

BigG — Fri, 31 Jul 2026 10:27:53 GMT

In my opinion, this device would work well with 8 x wheatstone bridge sensors, which don't require very high sampling rates. Although, the 16bit resolution is on the average side (many similar ADC's for bridge sensors offer 24bit). However the multiplexing / channel swapping settling in time is top end (micro seconds delay). I see it also includes a PGA (programmable gain amplifier), which is handy. Datalogging over days is where this device will be useful.

Unfortunately, I don't have a relevant application to test.

RE: What data would you acquire with this?

michaelkellett — Wed, 29 Jul 2026 09:57:33 GMT

I didn't vote - none of the suggestions fit.

This kind of box might be useful for multichannel applications but has several limitations that some people seem to have missed.

There is no specification for round trip latency - ie the time taken to measure an input and adjust an output - because of buffering and the USB interface it will be slow and jittery - so applications like DAB's acoustic levitation experiment won't work.

It's slow (as geralds has pointed out) - very slow, the 250kHz sampling rate is only true if you just use 1 channel, for 16 channels its 15.6kHz.

There is no input filtering - and the input bandwidth is approx 500kHz - so you will have noise problems.

So the extra bits had better include some way of doing filtering.

Looking back over many years of measuring stuff I can see it being useful in component testing where you might want to test several parts at once and over a long time and will need to build a decent test jig anyway. When I've done this I've mostly used a DMM or a DMM with multiplexing built in or a scope for faster stuff.

RE: What data would you acquire with this?

meera_hussien — Wed, 29 Jul 2026 08:09:10 GMT

I would like to use this in a project that i am currently working on to study the power and the performance of the motor and also the current consumption as well. This would be a handy tool to capture all the data that would be necessary for the studies.

RE: What data would you acquire with this?

geralds — Wed, 29 Jul 2026 07:28:42 GMT

Well, ADCs with 250 kB/s are relatively slow.

So, they're mainly suitable for measurements involving slow movements.

For example, an athlete running on a treadmill can be used to measure their vital signs.

Or in the field of chemistry, color gradients of chemical substances (I worked in the 1980s for a company that manufactured multi-input blood analyzers and chromatographs), or physical relationships in gears, the fracturing of materials, etc.

The analog outputs can be used, for example, for the fine-tuning of valve flaps.

Please read the spec.:
https://www.ni.com/docs/de-DE/bundle/usb-6421-specs/page/specs.html

The digital inputs/outputs can also control the associated devices, such as relays, valves, or other switching operations, to automate the measurements.

In the smart home sector, automated devices can now be easily controlled using the Raspberry Pi. This is what I see for my projects.

So, this was the hardware.

Software - here you have an extra cost, for the FlexLogger professional:

FlexLogger Professional (785748-3501)

FlexLogger Professional, Abonnementlizenz (Subscription license), Download

€ 575,00

Recommended for automated, extensible data logging with NI DAQ hardware. Automate tests with alarms, triggers, and events, and extend functionality with plug-ins.
Key Features
Multi-Chassis Synchronization: Synchronize multiple NI chassis for accurate, time-aligned measurements with a high channel count.
Logging Triggers: Automatically start, stop, or segment data recording based on sensor thresholds or other conditions to capture only what matters.
Events: Respond to specific occurrences during a test, such as activating devices when a condition is met (for example, starting cooling fans when the temperature exceeds a threshold).
Automation APIs: Control and monitor FlexLogger from external applications (Python, NI LabVIEW, or NI TestStand), enabling integration into larger automated test systems.
Computational Channels: Perform real-time mathematical operations on captured data (averages, RMS, custom formulas) to track derived measurements during test execution.
Plugins: Extend FlexLogger with custom LabVIEW or Python plugins to integrate third-party hardware, perform custom analyses, or connect to lab systems.
CAN/LIN Data Recording: Capture and record vehicle network data along with sensor measurements for complete vehicle or subsystem testing.

---

FlexLogger Lite (790818-35)

FlexLogger Lite, Abonnementlizenz, Herunterladen

kostenlos (free)

Recommended for fast, interactive data acquisition with NI-DAQ hardware. Quickly configure, view, and record sensor data—ideal for simple tests, no programming required.
Key Workflows
Configure Measurements—Quickly set up channels from NI-DAQ hardware, scale, and label signals so you can start capturing meaningful data immediately.
Create Dashboards—Build drag-and-drop dashboards with graphs, numeric displays, and other visuals to monitor live signals during a test.
Save Results—Save log data in standard TDMS or CSV formats for easy review, sharing, and analysis in tools like Excel, NI DIAdem, or the TDMS Viewer included with FlexLogger.

---

I would suggest the pro version.

RE: What data would you acquire with this?

arvindsa — Wed, 29 Jul 2026 03:42:16 GMT

16Bit at 250 kS/s/ch? I'd love to make it read high precision analog sensors, Especially GMR based rotation position sensor in the field of robot joint to verify a Toque-Velocity-Position Loop

RE: What data would you acquire with this?

DAB — Tue, 28 Jul 2026 18:49:55 GMT

Very interesting device.

I can see multiple projects for using the DAQ.

1. Drive speakers to see if you can get acoustic levitation.

2. Drive speakers to see mandalas patterns.

RE: What data would you acquire with this?

dougw — Tue, 28 Jul 2026 14:23:15 GMT

The only project I'm doing right now that could use this capability is a system with 8 piezo sensors that processes impact waveforms. The NI system could be used to capture raw waveforms that can be compared to the processed outputs.

RE: What data would you acquire with this?

gam3t3ch — Tue, 28 Jul 2026 13:22:16 GMT

I would use it to collect synchronized electrical, mechanical, and sensor data, including voltage, current, frequency, RPM, vibration, temperature, digital states, pulse timing, encoder position, startup behaviour, power consumption, and response to generated test signals. It would support automated testing of turntables, speakers, amplifiers, controllers, grounding systems, and other electronics, with the data logged for graphs, comparisons, fault detection, and pass/fail reports.

Do you want to take this for a spin?

cstanton — Fri, 24 Jul 2026 12:35:52 GMT

It kinda looks like a donut.

It's Vishay's RAIK060.

Full datasheet:
[View:/cfs-file/__key/communityserver-discussions-components-files/14/raik060.pdf:1050:410]

I think that this may need some parts with it to give it the full run, but wow the rotation speed is 10krpm? Zoomies. 60mm position sensor. Perhaps that needs some motor accompanyment.

[embed:33ecb077-39b7-4078-9b1e-dc3f977a690b:08696e6c-eb02-411e-acb7-fa8f309a50e2:question=What%20do%20you%20think%3F&description=&pollOptions=%5B%7B%22OptionId%22%3A%227f0dbcb1-30af-4b68-a8a8-12184713ac4a%22%2C%22Option%22%3A%22I%20mean%2C%20it%27s%20a%20thing%20for%20sure%2C%20I%27ll%20add%20my%20comment%20below%22%2C%22Ordinal%22%3A0%7D%2C%7B%22OptionId%22%3A%22fdd04feb-9ed5-4a6e-b5a2-97c134bb8998%22%2C%22Option%22%3A%22Can%27t%20be%20tested%20in%20isolation%2C%20I%20have%20parts%20suggestions%22%2C%22Ordinal%22%3A1%7D%2C%7B%22OptionId%22%3A%22016984af-456a-4278-8a09-3c602f182300%22%2C%22Option%22%3A%22I%27m%20not%20interested%2C%20don%27t%20call%20me%22%2C%22Ordinal%22%3A2%7D%2C%7B%22OptionId%22%3A%225253c888-a8f9-466c-bdb3-dbe51947f3cf%22%2C%22Option%22%3A%22I%27d%20like%20to%20know%20more%2C%20but%20I%20don%27t%20want%20to%20RoadTest%20it%22%2C%22Ordinal%22%3A3%7D%2C%7B%22OptionId%22%3A%22fd5a8991-830d-46cb-a607-bf47ea9f5862%22%2C%22Option%22%3A%22I%27ve%20actually%20been%20waiting%20for%20one%20of%20these%22%2C%22Ordinal%22%3A4%7D%2C%7B%22OptionId%22%3A%220a747e6b-d9ee-41ea-a9b6-4e674ebd60d4%22%2C%22Option%22%3A%22I%27ll%20comment%20below%2C%20I%20just%20wanted%20to%20see%20the%20results%22%2C%22Ordinal%22%3A5%7D%5D&ShowResultsConfiguration=1%2C0]

When we post forum threads such as this, they supplement our decisions on what RoadTests [mention:f9190b89a3144423a92cda972f7c734a:e9ed411860ed4f2ba0265705b8793d05] does now and in the future, and helps us to better position and suggest hardware to our supplier partners to offer to you, our members.

Thanks for joining in and sharing your thoughts.

RE: Do you want to take this for a spin?

rsc — Mon, 27 Jul 2026 18:31:32 GMT

I needed this a few years ago, we settled with a USB interface shaft encoder.

RE: Do you want to take this for a spin?

DAB — Sat, 25 Jul 2026 19:00:20 GMT

I could see this sensor as an excellent addition to my telescope mounting system.

That level of accuracy could be really useful for tracking objects and returning to exact positions.

Very interesting.

RE: Do you want to take this for a spin?

beacon_dave — Sat, 25 Jul 2026 13:59:13 GMT

A couple of these combined with the likes of a Egismos Laser Module (see e14 Presents episode 647) and perhaps a DIY 3D Disto / Total Station becomes a possibility.

RE: Do you want to take this for a spin?

strb — Sat, 25 Jul 2026 07:17:24 GMT

This is really interesting, but I don't have a suitable project to exploit this sensor.

RE: Do you want to take this for a spin?

dougw — Sat, 25 Jul 2026 06:26:23 GMT

This is an exciting technology, better in many ways than an RVDT. It has me thinking up applications where it would work well, even though I don't have an immediate need.

RE: Do you want to take this for a spin?

cstanton — Sat, 25 Jul 2026 00:57:24 GMT

Well, you really reach for the stars with that idea - is this something that you have access to? (I'd be jealous if you do)

RE: Do you want to take this for a spin?

mosfetbjtigbt — Fri, 24 Jul 2026 15:51:43 GMT

This might work very well integrated into the motor drive gear trains of an astronautical telescope drive for computer controlled star finder operation. Closed loop feedback would provide certainty in pointing as opposed to relying on stepper motors and making the assumptions of no slipping of gear shafts and backlash problems.

RE: Do you want to take this for a spin?

JWx — Fri, 24 Jul 2026 14:33:11 GMT

I wonder if single or multi-turn version is being considered for testing? Getting 10k RPM rotational speed for a fraction of the turn seems demanding...

RE: Do you want to take this for a spin?

cstanton — Fri, 24 Jul 2026 13:51:03 GMT

Community swag?

RE: Do you want to take this for a spin?

beacon_dave — Fri, 24 Jul 2026 13:40:13 GMT

Does it come with a safe full of swag ?

Automatic safe-cracker (On Her Majesty's Secret Service)

RE: Do you want to take this for a spin?

michaelkellett — Fri, 24 Jul 2026 12:58:16 GMT

It looks like fun but I don't have any current project for it.

I recently designed some tiny encoder boards which used a 4 quadrant single chip detector (from icHaus) and I couldn't test those properly either !

To do the sensor justice you would need some precision machined metal parts to install it and an application that cared about the resolution it can manage.

I could make the metal bits but I just don't have an application for the sensor (unless I could use it to test the tiny encoder......)

RE: Do you want to take this for a spin?

cstanton — Fri, 24 Jul 2026 12:56:28 GMT

[quote userid="418567" url="~/products/roadtest/f/forum/57128/do-you-want-to-take-this-for-a-spin/237532"]If I achieve 1mm precision on anything[/quote]

I somehow manage to when stubbing my toe every time I walk past the corner of the bed. ;)