Data Logging 3

[itsmoked]

I have to log pH and ORP stuff on a continual basis.
What are we using for data collection these days?

I think this is going to be 4-20mA or 0-5V. I can see that this will probably grow to more than two data stream too.

Eventually I'd also like to retrieve it wirelessly if possible so while the logger is logging I need to also be able to read it out.
A PLC Modbus crazy PLC will likely be involved too if that can be useful.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[MikeHalloran]

Sample rate?

Mike Halloran
Pembroke Pines, FL, USA

 

[itsmoked]

Let's say 8 channels every minute.
24Hrs x 60Minutes x 8ch

Likely 12bit data i.e. 2 bytes.

24x60x2 = 2880 bytes per day.

Preferably holding a month's data
2880 x 30 days = 100k of storage.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[btrueblood]

I use various devices from mccdaq.com, they work reliably and are cheap.

battery powered loggers -

http://www.mccdaq.com/solutions/Logger-Solutions.aspx

bluetooth wireless -

http://www.mccdaq.com/solutions/Wireless-Solutions.aspx

 

[itsmoked]

Thanks btrue, some nice loggers there.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[IRstuff]

Are you specifically looking for off the shelf loggers? Otherwise, I would think that Arduinos, Raspberry PIs, and a number of other single chip processors could do the same task.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529

 

[itsmoked]

Hi IR,
No not specifically OTS but that would probably be my first choice. There are other things going on that might make Arduinos/Raspberrys useful in these applications too so I'm certainly willing to entertain them.

Have you used either of them for data logging or even just analog inputs of any type with them?

Keith Cress
kcress -

http://www.flaminsystems.com

 

[zeusfaber]

The Arduino on its own is not bad for data acquisition of single-ended signals, but lacks onboard storage. It's not fantastically fast either, though I don't see that being a problem for the sort of job you're looking at. By the time you've added a shield with an SD card and another one to carry your analog scaling and buffering networks, the heap looks a bit ungainly (while remaining cheap as chips)

If the basic Arduino Uno doesn't have enough channels for your needs, there are larger models for only slightly less cheapness.

The Pi has no onboard A to D, so you'll need a shield to do that (and things like the Gertboard only have two A to D channels) - as well as scaling and buffering. I could only ever see me using it for data logging in conjunction with an OTS USB DAQ pod.

A.

 

[Sparweb]

No...
Go old school:

Sutron 8210
I'm using one for basically the same purpose, myself, and I have a few spares. Free if you pay shipping (North America)
I read all of your requirements above. It does everything you want (you aren't asking for much!)

STF

 

[itsmoked]

zeusfaber; Those ME-RedLabs look pretty nice. Perhaps a bit hard to get in the USA.

Spar; Those Sutrons look really well thought out and supported. You sure don't see manuals like that these days!
I'm intrigued. That might actually work. I appreciate the offer! What do you think postage would be to... say, San Fransisco?

Keith Cress
kcress -

http://www.flaminsystems.com

 

[btrueblood]

smoked, you can find similar stuff at my link too. In fact, they look like they come from the same chinese supplier, except the danes get theirs in red plastic instead of black...

 

[btrueblood]

Actually, those are licensed versions of the mccdaq products, they use the same software titles and everything.

 

[Sparweb]

itsmoked,
If you are seriously interested, please read:

http://www.fieldlines.com/index.php/topic,148892.msg1036004.html

You can contact me through that website, or through means available with Eng-Tips, or at the "obvious" URL. Make sure to append .ca not .com.


STF

 

[itsmoked]

Actually, those are licensed versions of the mccdaq products, they use the same software titles and everything.

Huh,I didn't see any that looked too similar I need to look again.


SparWeb; Thanks for the FLs link. I'll contact you.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[LionelHutz]

The red ME-Redlab boxes are Minilab 1008 modules. We use a bunch of them in test here. They have 4 differential or 8 single ended analog inputs. The 37 pin d-sub connector on the end is a bunch of digital I/O.

 

[itsmoked]

Thanks LH! I wasn't finding those. They certainly do appear to be the RedLab in a BlackLab sort of way. That's at a price-point that's more palatable too.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[zeusfaber]

Been away.

Lionel and BTrueblood are right - although I know there's another American firm that claims that the Minilab 1008 is in turn a copy of one of its own products.

A.