HMI for data logging with a scan rate of 1 ms.


Thread Starter

Devesh Yadav

Can any one help me in selecting a HMI along with PLC to get a data logging with a scan rate of 1 msec. Also suggest an option if available without PLC.

Devesh Yadav

Steve Myres, PE

Can you tell us how much data is to be logged? What kind of data? Is this continuous or periodically in a burst, like for a 30 second test approximately every 15 minutes?

If it just a few digital points, or a burst of data every so often, it may be more feasible to pre-pack the data in the PLC, and move large chunks out to long term storage.
Unless your using a very fast A/D, a 1ms scan rate will most likely just produce copious ammounts of data with little meaning. Most PLC A/D converters are not really all that fast, taking from 5-20 milliseconds for 12 bit resolution, some taking up towards 500 msec. for 16 bit resolution. Blinding speed is not the answer to every problem.

Sometimes event or threshold triggers or rate of change triggers are a better approach. If you absolutely have to have the fast scan rate, and your just logging data and not controlling, you might try something from National Instruments with a high speed card in your PC backplane. If your just temporarily logging high speed data, use a scope.

Hall, Christopher W

National Instruments do a range of products, both hardware and software that operate at kHz or even MHz frequencies. I suggest you check out their

Chris Hall

Mark Guthrie

Products I have looked at that are cable of your requirement , are the ABB MicroScada/RTU560 system and the Emerson DeltaV System.
Dear Devesh,

Our Vsystem can certainly read, store to disk and display data at 1KHz or even faster. I would keep the total number of IO points at this rate to
below 1,000 per computer if possible and if you are to use a regular operating system, Linux, Windows, Solaris or VMS for example, you will need a little buffering in the IO hardware.

For the IO, I am only aware of IO hardware that sits close to a computer, such as a PCI card or a VME card. With IP modules on a PCI card, one can
get 48 16-bit ADCs per PCI card each capable of 50KHz and each with 128Ksample memory. One can achieve similar densities and performance with a
VME card and VME expands the number of slots over the limited number that comes with a PC.

There are, of course, other hardware solutions that can give you rates above 50KHz.

Remember, if the system is to record continuously at this rate, one has a different design than if the system is to have the data in case of an
identified problem.

I hope that this helps,

Peter Clout
Vista Control Systems
Thanks Steve,
Could you tell me please how to pack the data in PLC and to retreive it back to HMI?
I am looking for the ABB RTU560 datasheet and any other material on this RTU. Can you help me with this?