Discrete Input Datalogger

Hey guys, got a quick question for you...

I am looking for a simple, cost effective, portable data logger for doing some simple counting applications.

Basically, I want to hook it up to anywhere from 1 to 8 photoeyes and do an event-based time stamp any time the beam is broken.

A quick internet search came up with many suitable devices, but I was hoping that someone here can give some recommendations based on personal experience.

There is, of course the PLC route, but this seems like overkill...

Thanks in advance!

Greetings DL06,

I assume that you need it to be a stand-alone not a PC-based device because you said "Portable"

If so, I think that the best price is for a very small PLC:
DL06 from AD (I'm sure you know this!)
Zelio from Shnieder (maybe lower price and will do the job)

If you need a PC-Based device:
I used RS485-based remote data acquisition devices from Adlink with great success.

www.adlinktech.com

And You have also the option of PCI Plug-in daq cards, I used some of these from Adlink and from www.ni.com

Another option is www.dataq.com which has many options with good prices for many of them, I don't have any experience with this company except that I purchased one of their starter kits for "playing", and it was good.

I agree a DL06 would be a good choice for this project, however there would be limitations as to how many timed stamped events could be recorded. There are 7616 words (8bit) of user memory.

Each event would have "day", "month","year", "hour", "minute" & mabye "second" Then the device. That 7 Vrams per event, x 8 devices = 56.
So you could record a total of 1088 events, or an average of 136 events per device.

Programming code for the recording portion would be short and fairly simple. Likely less then 10 rungs.

Thanks for the replies guys. I did look at the DL06, but the memory limitations eliminate it as a choice, unless I were to add a 6" C-more panel just for the compactflash datalogging capabilities. This would bring the total to about $1,000, plus I would have to buy the software (at least for the screen if my ladder was short enough to use the trial version). But I'm sure that there is something more cost effective.

I will be recording in the order of 10,000 events per channel in one logging session (I suppose I should have mentioned this in my initial post).

The option from dataq that you mentioned was along the lines of what I was looking at. I want something that is not PC based if possible, just a logger that I can set up then hook up to a PC to download the data.

I am a heavy user of the DataQ DI-730 instrument and I can't say enough good things about how useful and usable this product is. Since you mentioned low-cost, I would suggest their DI-148 bundle which includes an 8-input analyzer, software that lets you stream the data right into Excel and a cost of only $244! You'll need a laptop PC or nearby desktop PC with a USB serial port.

http://www.dataq.com/products/startkit/di148.htm

The input voltage range is only +/-10V. If your sensors operate on 24VDC, you will have to attach resistors to each sensor output in order to reduce the voltage into the analyzer.

Once you've used this type of analyzer, you'll never go back to an oscope. I have solved many dozens of difficult production machinery problems over the last several years using the DI-730 and strongly recommend the unit. Eight analog inputs, each one isolated from the other (unlike most o'scopes), 1000V input capability, multiple voltage ranges (microvolts up to hundreds of volts), 24/7 recording (great for intermittent problems), high-speed capability and much, much more.

For $244, you can't go wrong with the DI-248. If you need help with the resistors, let me know. Good Luck!

CeCo3

Thanks for the input. It looks like the 710, 715, and 718 series might do the trick since they are stand alone units.

Do you know if these units can trigger a record operation based on an event (i.e. sensor output) or if you are forced to use a fixed sample rate? Fixed sample rate would only work if there was a retentive counting function for each input.

Thanks again!

How did this work out for you? I have an application where I need a stand-alone battery powered logger to monitor motor start/stop times. All I need is 2 discrete inputs. I'm going to wire them to the motor starter auxillary contacts and I need to know what time of day the starters turn on and off. Then I need to print it out to show the customer that the duty cycles are too short. Anyone know a good solution for this? I checked Omega and Dataq but it seems like you either get 1 discrete or way too many, plus a pile of analog channels that I don't need.

Try a Logic Beach Crakker

jedft said:

How did this work out for you? I have an application where I need a stand-alone battery powered logger to monitor motor start/stop times. All I need is 2 discrete inputs. I'm going to wire them to the motor starter auxillary contacts and I need to know what time of day the starters turn on and off. Then I need to print it out to show the customer that the duty cycles are too short. Anyone know a good solution for this? I checked Omega and Dataq but it seems like you either get 1 discrete or way too many, plus a pile of analog channels that I don't need.

Click to expand...

69 bucks, 1 channel, since they are cheap, you just buy two of them, includes software. You plug it into your USB port, configure it, then wire it to the machine. After you are done, you plug it back into a USB port and save the data.
http://www.measurementcomputing.com/cbicatalog/USB-503.asp?dept_id=612&pf_id=1801


This one is 99 bucks, 24 channels, plugs into a USB port, comes with software, but you need to leave it attached to a computer.
http://www.measurementcomputing.com/cbicatalog/cbiproduct_new.asp?dept_id=415&pf_id=1537&mscssid=2P2F5Q4LBHCR8HH3MWUCH14V7KAHDJQB